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Screening preschool children with toothache: validation of the Brazilian version of the Dental Discomfort Questionnaire

Screening preschool children with toothache: validation of the Brazilian version of the Dental... Background: The Dental Discomfort Questionnaire (DDQ) is an observational instrument intended to measure dental discomfort and/or pain in children under 5 years of age. This study aimed to validate a previously cross-culturally adapted version of DDQ in a Brazilian children sample. Methods: Participants included 263 children (58.6% boys, mean age 43.5 months) that underwent a dental examination to assess dental caries, and their parent that filled out the cross-culturally adapted DDQ on their behalf. Exploratory factor analysis (principal component analysis form) and psychometric tests were done to assess instrument’s dimensionality and reliability. Results: Exploratory factor analysis revealed a multidimensional instrument with 3 domains: ‘eating and sleeping problems’ (Cronbach’s alpha 0.81), ‘earache problems’ (alpha 0.75), and ‘problems with brushing teeth’ (alpha 0.78). The assessment had excellent stability (weighted-kappa varying from 0.68 to 0.97). Based on the factor analysis, the model with all 7 items included only in the first domain (named DDQ-B) was further explored. The items and total median score of the DDQ-B were related to parent-reported toothache and the number of decayed teeth, demonstrating good construct and discriminant validities. Conclusions: DDQ-B was proven a reliable pain assessment tool to screen this group of Brazilian children for caries-related toothache, with good psychometric properties. Keywords: Toothache, Child, Preschool, Pain measurement, Validation studies Portuguese abstract Proposição: O Dental Discomfort Questionnaire (DDQ) é um instrumento observacional usado para avaliar dor de dente/desconforto em crianças menores de 5 anos de idade. Este estudo objetivou validar uma versão brasileira do DDQ, previamente adaptada transculturalmente. Métodos: 263 crianças participaram do estudo (58.6% meninos, com idade média de 43,5 meses), as quais foram examinadas clinicamente para avaliar a ocorrência de cárie, e seus pais preencheram individualmente a versão brasileira do DDQ. Para avaliar a dimensionalidade e confiabilidade do instrumento, foram realizados análise fatorial exploratória (tipo: análise de componentes principais) e testes psicométricos. (Continued on next page) * Correspondence: [email protected] Division of Pediatric Dentistry, Faculty of Dentistry, Federal University of Goias, Goiania, GO, Brazil Faculdade de Odontologia, Primeira Avenida, Setor Universitario, Goiania, GO, Brazil Full list of author information is available at the end of the article © 2014 Daher et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 2 of 9 http://www.hqlo.com/content/12/1/30 (Continued from previous page) Resultados: A análise exploratória fatorial revelou um instrumento multidimensional com 3 domínios: ‘problemas durante a mastigação e sono’ (alfa de Cronbach 0,81), ‘problemas relacionados à dor de ouvido’ (alfa 0,75), e ‘problemas durante a escovação’ (alfa 0,78). O instrumento mostrou excelente estabilidade (kappa ponderado variando de 0,68 a 0,97). Baseado nos resultados da análise fatorial exploratória, o modelo com os 7 itens incluídos no primeiro domínio, denominado DDQ-B, foi adicionalmente explorado. A frequência dos itens e o escore total do DDQ-B associaram-se a dor de dente relatada pelos pais das crianças e ao número de dentes cariados, confirmando as validades de construto e discriminante. Conclusão: O DDQ-B mostrou-se confiável e com boas propriedades psicométricas para avaliar este grupo crianças brasileiras apresentando dor de dente por cárie. Background prevalence of dental caries of 53.4% [12]. The occur- Pain, in general, is most reliably measured using self- rence of caries in children is considered to be an import- report, when available, given that pain is a subjective ant predictor of the onset of pain. One in five children experience [1]. Assessing pain in preschoolers and early- with decayed teeth (teeth with cavity due to caries) verbal children, however, presents special challenges, as present with toothache [13]. Furthermore, caries in pre- their cognitive capacities are still under-developed. As a schoolers is associated with lower quality of life due to result young children would describe pain in global and the effects of pain [14]. For this reason it is of great im- emotional terms and would have difficulties in perceiv- portance that toothache is recognized in young children ing, understanding, remembering and reporting pain [2]. and that appropriate treatment is sought to eliminate In addition, this cognitive immaturity often makes it the caries and the associated toothache. Besides using difficult for them to communicate verbally and, conse- proxy reports to assess toothache in this age group a ge- quently, to reliably self-report their pain [3,4]. neral pain assessment tools could be used [12,13,15,16]. To avoid the inaccurate assessment of pain in very These general tools, however, are not focused on spe- young children, it is recommended to use a validated cific behaviors that children can present as a result of observation tool that assesses pain based on the observa- having toothache and consequently toothache might stay tion of pain-related behaviors [5]. Alternatively, parents unrecognized. Therefore, it is better, when expecting can give a proxy report on children’s pain, as it has been toothache, to use a specific observational instrument that demonstrated that children’s pain as perceived by their focusses on toothache related behaviors such as the Den- parents is correlated with their self-report of pain [6,7]. tal Discomfort Questionnaire. Unfortunately, proxy reports of a child’s pain by their The Dental Discomfort Questionnaire (DDQ) is a be- parents or healthcare provider is often not exact. Both havioral observation tool developed to recognize tooth- over and underestimations of proxy reported pain of ache in children aged 5 years or younger, which focuses children are reported in the literature resulting in sub- on toothache-related pain behaviors [17]. The DDQ was optimal care [8,9]. developed in The Netherlands based on two concepts: 1) Recognizing toothache in preschool children is simi- caries and toothache in young children often results in larly inherently difficult. The tissue damage related to e.g., problems with eating, sleeping and brushing teeth dental caries, which often causes toothache, is not obvi- [15,16] and 2) children’s abilities to verbalize pain de- ous to parents. Consequently, parents regularly do not pends on their developmental cognitive stage [4]. To get realize that their child has a toothache. Furthermore, the an insight into which behaviors children with toothache behavioral expression of children as a result of toothache often display and to see if the presence of these particular is often thought by parents to be related to earache, a behaviors could be used to identify toothache, experienced type of pain that is more familiar to them. Dental caries, dentists interviewed parents of children with toothache to a disease that can result in toothache, however, is one of ask them about the behaviors of their children. These the most prevalent infectious diseases among preschool interviews resulted in a list of 12 behavior items for which children worldwide. For example: a recent study among the prevalence was tested in a group of young children 4-5-year-old Chinese children showed a prevalence of [17]. Eight out of the 12 behaviors in the list were found 72% of caries in primary teeth [10]; among 2-5-year-old to be more often present in children with caries and American children an increase of caries prevalence was toothache than in children without caries and toothache. found from 23% during the period 1998-1994 to 28% Three items concerning earache and one item concerning during the period 1999-2004 [11]; and the last natio- sleeping problems occurred frequently in both groups of nal survey of 5-year-old Brazilian children revealed a children and then were removed [17]. Those 8 items Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 3 of 9 http://www.hqlo.com/content/12/1/30 formed the DDQ. Psychometric properties of the 8-item Participants DDQ tested on preschoolers showed satisfactory internal Participants in this study included 263 children be- consistency (alpha 0.74) [17], as well as toothache predic- tween the ages of 25 and 60 months. Participants were tion ability (ROC area 0.88, CI 0.81-0.94). A score of 3 or approached during public health services for children, higher identified 78.0% of children with toothache in that including hospital outpatient clinics, dental clinics and study [18]. After children undergone dental treatment the day care centers. Children did not have any mental or total score of the DDQ significantly reduced in compari- physical disabilities and cooperated with the dental son with both before and immediately after treatment [19] examination. andafter an8weekfollow-up period [20],further sup- porting the validity of the DDQ. Finally, the developers The instrument: Dental Discomfort Questionnaire - DDQ of the DDQ also developed a version for children with The DDQ is an observational instrument for assessing learning disabilities [21]. Overall, the DDQ can be cate- dental discomfort and/or pain in very young children gorized as an ‘approaching well-establishment’ pain tool [17]. The DDQ contains questions to be completed by a [1,3], but its dimensionality has never been tested child’s parent or caregiver. The respondents were first through factor analysis. asked how often their child had a toothache. Potential To make the DDQ a ‘well-established’ pain tool it is responses included ‘never’, ‘sometimes’, ‘often’ and ‘Ido essential to do additional studies. Exploring the DDQ’s not know’. If s/he noticed that the child had a toothache, dimensionality by means of factor analysis and making the respondent reported when this occurred, i.e., ‘during the DDQ adaptable to different cultures is of particular meals’, ‘during the day’ or ‘during the night’. The second importance in the evidence-based process for improving part of the complete version of the original DDQ includes the instrument establishment [1,3]. Besides, toothache 12 items about different child behaviors that could be assessment studies are relevant because of the known associated with toothache or dental discomfort, which are impact toothache has on preschoolers’ quality of life and answered on a 3-point scale, as follows: 0 ‘never’,1 ‘some- the possible inherent inability of a child in this age group times’,and 2 ‘often’. The twelve items included in the to express it. complete version of the DDQ are as follows: 1. ‘Bites with The aim of this study was to validate a previously cross- molars instead of front teeth’;2. ‘Puts away something nice culturally adapted Brazilian version of the DDQ for caries- to eat’;3. ‘Cries during meals’;4. ‘Has problems with related toothache assessment in Brazilian preschoolers. brushing lower teeth’;5. ‘Has problems with brushing upper teeth’;6. ‘Has earache during the day’;7. ‘Has earache at night’;8. ‘Has earache during eating’;9. ‘Has Materials and methods problems chewing’;10. ’Chews on one side’;11. ‘Reaches The study described in this paper is the second phase of for the cheek while eating’;and 12. ‘Suddenly cries at night’. a larger study. In the first phase described in detail elsewhere (manuscript submitted to publication), the Procedures DDQ with 12-items was cross-culturally translated and The cross-culturally adapted version, which included 12 adapted to be used in Portuguese-Brazil-speaking chil- items, was completed by parents or guardians without dren’s caregivers, according to a universalistic approach interference from the interviewer while their children method [22]. Figure 1 depicts this cross-cultural adapta- had a dental exam. One of three pediatric dentists exam- tion phase, including conceptual and item equivalences, ined children’s dentition status following the World semantic equivalence and operational equivalence. Phase Health Organization (WHO) recommendations [24], after two is related to the measurement and functional equiva- training and calibration. A convenience random sample of lences that are addressed in the current study (validation 14 children was dentally reexamined in a one-week process). The second phase did not involve participants interval by the three pediatric dentists to determine the included in the first phase of this study. intra-examiner agreement. Inter-examiner agreement This study was independently reviewed and approved was measured through pictures: The three pediatric by the Institutional Research Board of the Federal Uni- dentists examined 12 photographs showing teeth of versity of Goias, city of Goiania, State of Goias, Brazil children under 5-years old, for 1 minute and registered (protocol #127/09). Consent was sought from all partici- the affected teeth according to the WHO decayed, pants (parents on behalf of their children): after they un- missing, filled tooth index (dmft) (in lux calibration). derstood the aims, risks, benefits and other characteristics Intra and inter-examiner agreement regarding dmft index of this investigation, they signed a written consent form to were tested with kappa. The intra-examiner kappa varied participate in this study. All phases of this study were done from 0.82 to 0.98 for the three pediatric dentists. Taken in full accordance with ethical principles, including the the dentists’ results in pairs, inter-examiner reliability World Medical Association Declaration of Helsinki [23]. varied from 0.76 to 0.90. Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 4 of 9 http://www.hqlo.com/content/12/1/30 Figure 1 Flowchart of cross-cultural adaptation. Flowchart of the universalistic approach method used to cross-culturally adapt the Dental Discomfort Questionnaire (DDQ), Brazilian-Portuguese version. The examiner used a mouth mirror, a WHO periodon- Statistical analysis tal probe, an artificial LED head lamp (Microdont Star All statistical analyses were carried out using the IBM Light KD 200, Sao Paulo, Brazil) and personal protective Statistical Package for Social Science 19.0 (SPSS Inc., equipment. Children were examined while seated in a Chicago, IL, USA). Statistical significance was set at chair or in their parents’ laps (small children), with the P <0.05. examiner seated in front of the chair. Dentition status was determined using the WHO caries diagnostic criteria Test-retest reliability (dmft index) [24]. Dental codes were written down on a For the test-retest reliability assessment, we calculated spreadsheet by a recording clerk. Children with one or the sample size using the 2 times k formula, where k is more teeth scored as ‘decayed’ or ‘filled with additional the number of points on the scale [25]. As the DDQ decay’ were considered to have decayed teeth. is a three-point scale, k = 3. According to the formula Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 5 of 9 http://www.hqlo.com/content/12/1/30 (2 times “3squared”), a sample of 18 individuals would Exploratory factor analysis and internal consistency be sufficient for this specific test. We included a con- A total of 211 questionnaires were included for explora- venience sample of 38 parents to complete again the tory factor analysis, principal component analysis (PCA) adapted version of the DDQ (with 12-items) one week form. In 52 cases, parents did not complete the 12 items after the first questionnaire was administered. The of the survey; therefore, these questionnaires were ex- test-retest reliability coefficients of each DDQ item cluded from further analysis. The remaining question- were calculated using the weighted-kappa [26]. naires showed good sampling adequacy and sphericity for correlation assessment among the items to proceed with the PCA. Indeed, Bartlett’s Test of Sphericity showed a Exploratory factor analysis and internal consistency significant correlation among items (P < 0.001), and the The dimensionality of the adapted 12-item version was Kaiser-Meyer-Olkin Measure of Sampling Adequacy assessed through exploratory factor analysis: principal (MSA) reached a value of 0.77. component analysis (PCA) form with orthogonal varimax Next, the factors using PCA with orthogonal varimax rotation. Bartlett’s Test was used to assess sphericity and rotation were extracted. Of the 12 possible factors ex- the Kaiser-Meyer-Olkin was used to measure of Sampling tracted, three were considered relevant (Eigenvalues > 1). Adequacy (MSA) [27]. The number of factors in the This model explained 58.2% of the total variance. Table 1 instrument was reduced by using the Kaiser criterion presents the factor loadings for each item after varimax (Eigenvalues over 1.0) [27]. The varimax rotation method rotation. The first factor aggregated items about func- was chosen to minimize the likelihood of two or more sig- tions related to mastication and possible discomfort dur- nificant factors loading for each item by maximizing the ing eating or sleeping and was called the ‘eating and extent to which factors were independent of each other sleeping problems’ domain. The second factor addressed [28]. Item values were retained if they had a primary factor earache, which was reported in different periods; this loading of >0.40 and a secondary factor loading of <0.30 was called the ‘earache problems’ domain. Finally, the [29]. After the PCA, the internal consistency of the differ- third factor focused on problems brushing one’s upper ent factors was assessed using Cronbach’salpha [30]. We or lower teeth and was called the ‘problems with brush- expected to find two factors: one related to earache prob- ing teeth’ domain. lems (3 items) and other comprising the other 9 items. The reliability analysis for each extracted factor showed that the questionnaire with items from the first domain Construct and discriminant validity (‘eating and sleeping problems’) had a good internal Construct validity was tested by associating the median consistency (Cronbach’s alpha coefficient 0.81), while the total score of children with and without parent-reported other two domains had acceptable Cronbach’salpha,0.75 toothache (dichotomized as yes = ‘sometimes’ and ‘often’, and 0.78 respectively (Table 1) [29]. Alpha coefficients and no = ‘never’) (Mann-Whitney U Test) and correlating could not be improved by the exclusion of any item, and it with the number of decayed teeth (Spearman correl- all 12 items had good convergent validity (item scale ation). For discriminant validity, frequencies of the pain- correlation ≥ .40). related behaviors (DDQ items) and the median of DDQ The first factor of DDQ was named DDQ-Brazil total score were compared between four clinical groups of (DDQ-B) and was further explored. The other two factors children, divided accordingly to the occurrence of caries were not considered for the additional analyses. and toothache reported by parents [31]. Construct and discriminant validity analysis of DDQ-B In response to the toothache question, parents reported Results that 46.4% (n = 122) of their children ‘never’ had tooth- Participants ache, 38.4% (n = 101) had such pain ‘sometimes’,9.9% Participants in this study included 263 children, 109 girls (n = 26) had such pain ‘often’, and the parents of 14 and 154 boys, between the ages of 25 and 60 months (5.3%) did not know. Parents of participating children (mean 43.5, SD 9.8), and their parents who completed reported that 42.3% (n = 111) had toothache during eating, the questionnaires. Most questionnaires were filled out 40% (n = 105) had it during the day, and 20% (n = 52) had by mothers (84.8%), followed by fathers (9.5%) and toothache at night. Sixty percent of children had decayed grandmothers (5.7%). teeth (n = 158). Regarding children with reported tooth- ache, parents reported more toothache (‘sometimes’ and Test-retest reliability ‘often’) for children with decayed teeth (n = 112, 88.2%) The test-retest reliability of the 12-item adapted DDQ than for children without decayed teeth (n = 15, 11.8%) using a weighted-kappa for all items showed an excellent (P < 0.001, Chi-square test). Four clinical groups based stability for most items of the instrument (Table 1). on the combination of decayed teeth and toothache Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 6 of 9 http://www.hqlo.com/content/12/1/30 Table 1 Factor loadings after varimax rotation of the three components extracted and results of test-retest reliability for each DDQ item (a) DDQ items Factor 1–‘Eating and Factor 2–‘Earache Factor 3–‘Problems Weighted-kappa coefficient (b) sleeping problems’ problems’ with brushing teeth’ (95% Confidence Interval) Cries during meals 0.79 −0.26 −0.09 0.88 (0.74-1.00) Reaches for the cheek while eating 0.77 0.24 0.06 0.75 (0.55-0.96) Puts away something nice to eat 0.70 0.01 0.16 0.74 (0.52-0.96) Suddenly cries at night 0.60 0.24 0.27 0.84 (0.69-0.98) Chews on one side 0.59 0.28 0.17 0.97 (0.92-1.00) Has problems chewing 0.53 0.20 0.36 0.77 (0.61-0.94) Bites with molars instead of front teeth 0.47 −0.08 0.30 0.68 (0.49-0.88) Has earache during the day 0.04 0.86 0.07 0.80 (0.59-1.00) Has earache at night 0.05 0.75 0.07 0.94 (0.84-1.00) Has earache during eating 0.22 0.72 0.07 0.94 (0.83-1.00) Has problems with brushing lower teeth 0.07 0.09 0.87 0.86 (0.71-1.00) Has problems with brushing upper teeth 0.26 0.11 0.84 0.75 (0.57-0.93) Eigenvalues 4.08 1.62 1.28 % of variance 34.04 13.52 10.67 Cronbach’s alpha coefficient 0.81 0.75 0.78 (a) (b) Items ordered by factor analysis. Test-retest reliability. The numbers in bold refer to the highest factor loading for each item. reported by parents (excluding the questionnaires with related behaviors and the median total DDQ-B scores are the ‘did not know’ marked option for toothache ques- displayed in Table 2 and show the discriminant validity of tion, n = 14) were identified: children with decayed DDQ-B in identifying children with decayed teeth and teeth and toothache (children with caries-related tooth- toothache. The median total DDQ-B score of children ache) (group 1, n = 112); children with decayed teeth with decayed teeth and toothache was higher than the but no toothache (group 2, n = 46); children without median total scores of children included in other groups decayed teeth but with toothache (group 3, n = 15); and (P < 0.001, Mann-Whitney test). Moreover, children with children without decayed teeth or toothache (children decayed teeth and toothache (group 1) exhibited all of the without caries-related toothache) (group 4, n = 76). pain-related behaviors on DDQ-B more often than caries- The median total score on the DDQ-B was 2.0 (first- free children and those without parent-reported toothache third quartile 1.0-5.0), and scores ranged from 0 to 13. (group 4) (P < 0.01, Mann-Whitney test). There was no The children’s ages did not correlate with the total score difference between children with decayed teeth without (Spearman’s rho = 0.08, P = 0.17). Boys had higher me- toothache and children without decayed teeth with tooth- dian total scores (3.0, first-third quartile 1.0-6.0) than ache (groups 2 and 3) in any of the individual items or girls (2.0, first-third quartile 0.5-4.0) (P = 0.01, Mann- median total scores. Whitney test); there were no differences between boys and girls in toothache reported by parents (P = 0.71, Discussion Chi-Square test). The psychometric characteristics of a cross-culturally Children whose parents reported toothache presented adapted version of the Dental Discomfort Questionnaire with higher total DDQ-B scores (median 4.0, first-third (DDQ) to the Brazilian culture were satisfactory. A shorter quartile 2.0-7.0) than those with no toothache (median model of DDQ with 7 items, named DDQ-B, was further 1.0, first-third quartile 0.0-3.0) (P < 0.001, Mann-Whitney explored and validated as a preschooler toothache as- test). Moreover, children with higher DDQ-B scores had a sessment tool, presenting adequate psychometric and higher number of decayed teeth (Spearman’s rho = 0.42, discriminant properties. The ability to discriminate be- P < 0.001). tween the presence and absence of pain is the most The clinical groups (1, 2, 3 and 4) were characterized important quality of any pain assessment measure [32]. by different frequencies of pain-related behaviors (P <0.05, The initial 12-item Brazilian Portuguese adaptation of Kruskal-Wallis test) and different median total DDQ-B the DDQ was found to be a multidimensional instru- scores (P < 0.001, Kruskal-Wallis test). The seven pain- ment with three clearly distinct domains: ‘eating and Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 7 of 9 http://www.hqlo.com/content/12/1/30 Table 2 Frequency of ‘sometimes’ and ‘often’ for each Dental Discomfort Questionnaire–Brazilian version (DDQ-B) item and DDQ-B total scores for different clinical groups Pain-related behaviors from the n (%) DDQ-B (‘sometimes’ and ‘often’) Children with decayed Children with decayed Children without decayed Children without decayed teeth and a toothache teeth without a toothache teethwithatoothache teeth or a toothache a a a,b b Bites with molar instead of front teeth 70 (62.5) 27 (60.0) 8 (53.3) 33 (43.4) a b b b Puts away something nice to eat 58 (51.8) 12 (26.1) 1 (6.7) 12 (15.8) a b b b Crying during meals 68 (60.7) 8 (17.4) 3 (20.0) 10 (13.2) a b b b Problems chewing 61 (54.5) 12 (27.3) 2 (13.3) 11 (14.5) a b b,c c Chewing on one side 54 (61.4) 12 (34.3) 3 (23.1) 10 (15.9) a b b b Reaching for the cheek while eating 68 (60.7) 9 (20.4) 4 (26.7) 8 (10.5) a b b b Suddenly cries at night 64 (57.1) 16 (36.4) 7 (46.7) 21 (27.6) a b b,c c Median total DDQ-B score 5.0 (2.5-7.0) 2.0 (1.0-4.0) 2.0 (1.0-3.5) 1.0 (0-2.0) (first-third quartile) The same letter indicates an insignificant difference, whereas different letters indicate significant differences (P < 0.05) among groups. sleeping problems’, ‘earache problems’ and ‘problems this age range, boys may still be more emotionally ex- with brushing teeth’. Previous study [17] affirmed that pressive than girls; however, at around six years old, the DDQ could be seen as a one-dimensional scale, boys become less likely than girls to express hurt or although that statement was based on its satisfactory distress, as they are made to feel ashamed of their feel- internal consistency only and not on factor analysis. Our ings of weakness [34]. aprioristic expectation of two factors was partially con- One limitation of this study is that the gold standard firmed; however, a third “unexpected” factor included measure of toothache was parental report. This could the two items related to “tooth brushing problems”, and potentially result in an imperfect reference standard we understand that they might be observed in stubborn [35]. To minimize this bias, the occurrence of caries was young children that might have not been in pain. Explor- also assessed and was found to be associated with the ing each factor individually, the ‘eating and sleeping presence of toothache. Parents reported more toothache problems’ domain, which included 7 items, showed the when children had decayed teeth (caries) than when they highest internal consistency. Moreover, this domain on did not. To further eliminate bias for parts of our ana- its own demonstrated a high test-retest reliability, which lysis we chose to exclude the children who had caries supports excellent stability. Together, these findings but for whom the parents indicated they did not have suggest that the 7-item DDQ-B has good psychomet- toothache (possible false negatives) and the children ric properties. The repeated psychometric analyses who did not have caries but for whom the parents indi- described in this study strengthen the properties of cated they did have toothache (possible false positives). the DDQ. Analyses performed in different situations/ A previous cohort study similarly showed that toothache research groups are criteria for a “well-established” is rare in caries-free children but common in children pain assessment tool for use with children in clinical who had caries [13]. The use of different methods in a settings [1,3]. gradual process of validation with confirmation of the Pain-related behaviors are important indicators for the meaning of the analyzed data is recommended [35]. This assessment of pain in preverbal children [6]. As stated in approach was done for construct and discriminant tests our results, pain-related eating and sleeping behaviors in an attempt to improve parent-reported toothache as the gold standard as for very young children, self- were found to be more frequently displayed by children with decayed teeth and toothache than in children who reporting could be misinterpreted [5]. were caries-free and without toothache. In another One way to address the lack of a true gold standard was to conceptualize pain as a latent variable (one that study, it was also found that problems eating certain foods, as reported by parents, were more prevalent in cannot be observed) and use the results of the present young children with decayed teeth than without [15]. exploratory factor analysis to generate hypotheses for confirmatory factor analysis [27,31]. Therefore, further Interestingly, we found that boys had higher DDQ-B scores than girls, but there were no significant sex studies with larger samples should be conducted in the differences found in the incidence of toothache as future to estimate the measurement error when analyz- ing the relationships between DDQ items. reported by parents. This result might be due to the interplay between pain expression, socialization and gen- Furthermore, the item ‘bites with molars instead of der [33]. The presented study focused on preschoolers. In front teeth’ should be viewed with caution, as it does not Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 8 of 9 http://www.hqlo.com/content/12/1/30 discriminate between children with toothache. It was Acknowledgements We are grateful to the team, which included graduate and undergraduate kept in the DDQ-B because its removal would not students, of the Pediatric Dental Sedation Clinic (‘Núcleo de Estudos em improve the Cronbach’s alpha. It may be that parents Sedação Odontológica’, NESO) at the Federal University of Goias (UFG) for have difficulties observing whether a child is biting with their support. This research was supported by grants from the Brazilian Federal Agency for Support and Evaluation of Postgraduate Education the front or back teeth. (CAPES), the National Council for Scientific and Technological Development, The DDQ-B offers unique benefits in the assessment Brazil (CNPq), and the Research Foundation of the State of Goias, Brazil of toothache and the subsequent prioritization of dental (FAPEG). treatment among Brazilian children. For the assessment Author details of toothache, there is only one validated Brazilian in- Health Sciences Graduate Program, Federal University of Goias, Goiania, GO, strument (the Child Dental Pain Questionnaire, child- Brazil. Department of Adolescent Medicine, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada. Division of Prosthetic Dentistry, DPQ) with good psychometric properties (ICC = 0.99 Faculty of Dentistry, Federal University of Goias, Goiania, GO, Brazil. Division and Cronbach’s alpha 0.81), but it is used only with of Pediatric Dentistry, Faculty of Dentistry, Federal University of Goias, children between the ages of 8 and 10 years [36]. More- Goiania, GO, Brazil. Faculdade de Odontologia, Primeira Avenida, Setor Universitario, Goiania, GO, Brazil. over, relevant oral health epidemiological data shows children’s need for a validated instrument: more than Received: 6 July 2013 Accepted: 27 February 2014 half of Brazilian children who are 5 years of age and Published: 4 March 2014 under have caries in primary dentition according to a recent national government study [12]. Similar high caries References 1. von Baeyer CL, Spagrud LJ: Systematic review of observational prevalence are found in this age group in Southern (40% (behavioral) measures of pain for children and adolescents aged 3 to 18 of children 0 to 5 years old) [37] and Northern Brazil (62% years. Pain 2007, 127:140–150. of children 2 to 4 years old) [15]. Moreover, 25% of 2. Harbeck C, Peterson L: Elephants dancing in my head: a developmental approach to children’s concept of specific pains. Child Dev 1992, parents/caregivers of preschoolers in Brazil indicated 63:138–149. theirchild hadahistoryofsometypeof toothachein 3. Cohen LL, Lemanek K, Blount RL, Dahlquist LM, Lim CS, Palermo TM, their lifetime [16]. McKenna KD, Weiss KE: Evidence-based assessment of pediatric pain. J Pediatr Psychol 2008, 33:939–955. As our sample was not representative of the Brazilian 4. von Baeyer C, Uman LS, Chambers CT, Gouthro A: Can we screen young population, caution should be taken when generalizing the children for their ability to provide accurate self-reports of pain? results. Nonetheless, the present findings adds to the litera- Pain 2011, 152:1327–1333. 5. Howard R, Carter B, Curry J, Morton N, Rivett K, Rose M, Tyrrell J, Walker S, ture and support an instrument that can be applied in clin- Williams G: Association of paediatric anesthetists of Great Britain and ical practice and in research, in private office and in public Ireland: pain assessment. Paediatr Anaesth 2008, 18(Suppl 1):14–18. services, to help with the diagnosis of a condition that affects 6. Shaikh N, Kearney DH, Colborn DK, Balentine T, Feng W, Lin Y, Hoberman A: How do parents of preverbal children with acute otitis media determine the quality of life of children worldwide. Yet, our results how much ear pain their child is having? J Pain 2010, 11:1291–1294. indicate that the original DDQ psychometric properties 7. Versloot J, Veerkamp JSJ, Hoogstraten J: Assessment of pain by child, should be reassessed in English-speaking cultures. dentist, and independent observers. Pediatr Dent 2004, 26:445–449. 8. Manworren RC: It’s time to relieve children’s pain. J Spec Pediatr Nurs 2007, In summary, the 7 items-model of the Brazilian ver- 12:196–198. sion of the Dental Discomfort Questionnaire (DDQ-B) is 9. Chambers CT, Reid GJ, Craig KD, McGrath PJ, Finley GA: Agreement a reliable and validated toothache assessment tool for between child and parent reports of pain. Clin J Pain 1998, 14:336–342. 10. Li Y, Zhang Y, Yang R, Zhang Q, Zou J, Kang D: Associations of social and screening caries-related toothache among 2- to 5-year-old behavioural factors with early childhood caries in Xiamen city in China. preschool children and has good psychometric properties. Int J Paediatr Dent 2011, 21:103–111. Children’s eating- or sleeping-related problem behaviors 11. Dye BA, Tan S, Smith V, Lewis BG, Barker LK, Thornton-Evans G, Eke PI, Beltrán-Aquilar ED, Horowitz AM, Li CH: Trends in oral health status: would seem to be the most suitable areas of concern for United Sates, 1988-1994 and 1999-2004: National Center for Health toothache assessment purposes and should be systematic- Statistics. Vital Health Stat 11 2007, 248:1–92. ally investigated. Finally, the presented methodology 12. Ministry of Health of Brazil: SB Brazil 2010 Project: National Research on Oral Health. Brasilia: Main Results; 2011. sequence could be used in future research to adapt the 13. Tickle M, Blinkhorn AS, Milsom KM: The occurrence of dental pain and DDQ and other observational instruments to other extractions over a 3-year period in a cohort of children aged 3-6 years. cultures and languages. J Public Health Dent 2008, 68:63–69. 14. Easton JA, Landgraf JM, Casamassimo PS, Wilson S, Ganzberg S: Evaluation Competing interests of a generic quality of life instrument for early childhood caries-related The authors declare that they have no competing interests. pain. Community Dent Oral Epidemiol 2008, 36:434–440. 15. Gradella CM, Bernabé E, Bönecker M, Oliveira LB: Caries prevalence and Authors’ contributions severity, and quality of life in Brazilian 2- to 4-year-old children. AD designed and conducted the study, analyzed the data, and wrote the Community Dent Oral Epidemiol 2011, 39:498–504. manuscript. JV is the DDQ developer, designed the study, analyzed the data, 16. Moura-Leite FR, Ramos-Jorge ML, Bonanato K, Paiva SM, Vale MP, Pordeus and wrote the manuscript. CRL contributed with the statistical knowledge, IA: Prevalence, intensity and impact of dental pain in 5 year-old analyzed the data and wrote the final reviewed version of the manuscript. preschool children. Oral Health Prev Dent 2008, 6:295–301. LRC was responsible for the study supervision, designed and conducted the 17. Versloot J, Veerkamp JS, Hoogstraten J: Dental discomfort questionnaire: study, analyzed the data, and wrote the manuscript. All authors reviewed assessment of dental discomfort and/or pain in very young children. and approved the final manuscript prior to its submission. Community Dent Oral Epidemiol 2006, 34:47–52. Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 9 of 9 http://www.hqlo.com/content/12/1/30 18. Versloot J, Veerkamp JS, Hoogstraten J: Dental discomfort questionnaire: predicting toothache in preverbal children. Eur J Paediatr Dent 2004, 5:170–173. 19. Costa LR, Harrison R, Aleksejuniene J, Nouri MR, Gartner A: Factors related to postoperative discomfort in young children following dental rehabilitation under general anesthesia. Pediatr Dent 2011, 33:321–326. 20. Versloot J, Veerkamp JS, Hoogstraten J: Dental discomfort questionnaire for young children before and after treatment. Acta Odontol Scand 2005, 63:367–370. 21. Versloot J, Hall-Scullin E, Veerkamp JS, Freeman R: Dental discomfort questionnaire: its use with children with a learning disability. Spec Care Dentist 2008, 28:140–144. 22. Herdman M, Fox-Rushby J, Badia X: A model of equivalence in the cultural adaptation of HRQoL instruments: the universalist approach. Qual Life Res 1998, 7:323–335. 23. World Medical Association Declaration of Helsinki - ethical principles for medical research involving human subjects. http://www.wma.net/en/ 30publications/10policies/b3/index.html. 24. World Health Organization: Oral health surveys: basic methods. Geneva: World Health Organization; 1997. 25. Cicchetti DV, Fleiss JL: Comparison of the null distribution of weighted kappa and the C ordinal statistic. Appl Psych Meas 1977, 1:195–201. 26. Cicchetti DV, Sparrow SS: Developing criteria for establishing interrater reliability of specific items: applications to assessment of adaptive behavior. Am J Ment Def 1981, 86:127–137. 27. Norman GR, Streiner DL: Biostatistics: the bare essentials. Shelton: People’s Medical Publishing House; 2008. 28. Field A: Exploratory factor analysis. In Discovering statistics using SPSS. 2nd edition. Edited by Field A. London: Sage; 2009:627–685. 29. Manly BFJ: Factor analysis. In Multivariate statistical methods. Edited by Manly BFJ. London: Chapman & Hall; 1994:93–106. 30. Cicchetti DV, Sparrow SS: Assessment of adaptive behavior in young children. In Developmental assessment in clinical child psychology: a handbook. Edited by Johnson JJ, Goldman J. New York: Pergamon Press; 1990:173–196. 31. Streiner DL, Norman GR: Health measurement scales: a practical guide to their development. Oxford: Oxford University Press; 2008. 32. Breau LM, McGrath PJ, Camfield CS, Finley GA: Psychometric properties of the non-communicating children’s pain checklist-revised. Pain 2002, 99:349–357. 33. Hoffmann DE, Tarzian AJ: The girl who cried pain: a bias against women in the treatment of pain. J Law Med Ethics 2001, 29:13–27. 34. Pollack W: Real Boys: Rescuing Our Sons from the Myths of Boyhood. New York: Henry Holt & Co; 1998. 35. Rutjes AW, Reitsma JB, Coomarasamy A, Khan KS, Bossuyt PM: Evaluation of diagnostic tests when there is no gold standard: a review of methods. Health Technol Assess 2007, 11:3. ix-51. 36. Barrêtto ER, Paiva SM, Pordeus IA, Ferreira e Ferreira E: Validation of a child dental pain questionnaire instrument for the self-reporting of toothache in children. Pediatr Dent 2011, 33:228–232. 37. Ferreira SH, Béria JU, Kramer PF, Feldens EG, Feldens CA: Dental caries in 0- to 5-year-old Brazilian children: prevalence, severity and associated factors. Int J Paediatr Dent 2007, 17:289–296. doi:10.1186/1477-7525-12-30 Cite this article as: Daher et al.: Screening preschool children with toothache: validation of the Brazilian version of the Dental Discomfort Questionnaire. Health and Quality of Life Outcomes 2014 12:30. Submit your next manuscript to BioMed Central and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color figure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Health and Quality of Life Outcomes Springer Journals

Screening preschool children with toothache: validation of the Brazilian version of the Dental Discomfort Questionnaire

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Copyright © 2014 by Daher et al.; licensee BioMed Central Ltd.
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Medicine & Public Health; Quality of Life Research; Quality of Life Research
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Abstract

Background: The Dental Discomfort Questionnaire (DDQ) is an observational instrument intended to measure dental discomfort and/or pain in children under 5 years of age. This study aimed to validate a previously cross-culturally adapted version of DDQ in a Brazilian children sample. Methods: Participants included 263 children (58.6% boys, mean age 43.5 months) that underwent a dental examination to assess dental caries, and their parent that filled out the cross-culturally adapted DDQ on their behalf. Exploratory factor analysis (principal component analysis form) and psychometric tests were done to assess instrument’s dimensionality and reliability. Results: Exploratory factor analysis revealed a multidimensional instrument with 3 domains: ‘eating and sleeping problems’ (Cronbach’s alpha 0.81), ‘earache problems’ (alpha 0.75), and ‘problems with brushing teeth’ (alpha 0.78). The assessment had excellent stability (weighted-kappa varying from 0.68 to 0.97). Based on the factor analysis, the model with all 7 items included only in the first domain (named DDQ-B) was further explored. The items and total median score of the DDQ-B were related to parent-reported toothache and the number of decayed teeth, demonstrating good construct and discriminant validities. Conclusions: DDQ-B was proven a reliable pain assessment tool to screen this group of Brazilian children for caries-related toothache, with good psychometric properties. Keywords: Toothache, Child, Preschool, Pain measurement, Validation studies Portuguese abstract Proposição: O Dental Discomfort Questionnaire (DDQ) é um instrumento observacional usado para avaliar dor de dente/desconforto em crianças menores de 5 anos de idade. Este estudo objetivou validar uma versão brasileira do DDQ, previamente adaptada transculturalmente. Métodos: 263 crianças participaram do estudo (58.6% meninos, com idade média de 43,5 meses), as quais foram examinadas clinicamente para avaliar a ocorrência de cárie, e seus pais preencheram individualmente a versão brasileira do DDQ. Para avaliar a dimensionalidade e confiabilidade do instrumento, foram realizados análise fatorial exploratória (tipo: análise de componentes principais) e testes psicométricos. (Continued on next page) * Correspondence: [email protected] Division of Pediatric Dentistry, Faculty of Dentistry, Federal University of Goias, Goiania, GO, Brazil Faculdade de Odontologia, Primeira Avenida, Setor Universitario, Goiania, GO, Brazil Full list of author information is available at the end of the article © 2014 Daher et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 2 of 9 http://www.hqlo.com/content/12/1/30 (Continued from previous page) Resultados: A análise exploratória fatorial revelou um instrumento multidimensional com 3 domínios: ‘problemas durante a mastigação e sono’ (alfa de Cronbach 0,81), ‘problemas relacionados à dor de ouvido’ (alfa 0,75), e ‘problemas durante a escovação’ (alfa 0,78). O instrumento mostrou excelente estabilidade (kappa ponderado variando de 0,68 a 0,97). Baseado nos resultados da análise fatorial exploratória, o modelo com os 7 itens incluídos no primeiro domínio, denominado DDQ-B, foi adicionalmente explorado. A frequência dos itens e o escore total do DDQ-B associaram-se a dor de dente relatada pelos pais das crianças e ao número de dentes cariados, confirmando as validades de construto e discriminante. Conclusão: O DDQ-B mostrou-se confiável e com boas propriedades psicométricas para avaliar este grupo crianças brasileiras apresentando dor de dente por cárie. Background prevalence of dental caries of 53.4% [12]. The occur- Pain, in general, is most reliably measured using self- rence of caries in children is considered to be an import- report, when available, given that pain is a subjective ant predictor of the onset of pain. One in five children experience [1]. Assessing pain in preschoolers and early- with decayed teeth (teeth with cavity due to caries) verbal children, however, presents special challenges, as present with toothache [13]. Furthermore, caries in pre- their cognitive capacities are still under-developed. As a schoolers is associated with lower quality of life due to result young children would describe pain in global and the effects of pain [14]. For this reason it is of great im- emotional terms and would have difficulties in perceiv- portance that toothache is recognized in young children ing, understanding, remembering and reporting pain [2]. and that appropriate treatment is sought to eliminate In addition, this cognitive immaturity often makes it the caries and the associated toothache. Besides using difficult for them to communicate verbally and, conse- proxy reports to assess toothache in this age group a ge- quently, to reliably self-report their pain [3,4]. neral pain assessment tools could be used [12,13,15,16]. To avoid the inaccurate assessment of pain in very These general tools, however, are not focused on spe- young children, it is recommended to use a validated cific behaviors that children can present as a result of observation tool that assesses pain based on the observa- having toothache and consequently toothache might stay tion of pain-related behaviors [5]. Alternatively, parents unrecognized. Therefore, it is better, when expecting can give a proxy report on children’s pain, as it has been toothache, to use a specific observational instrument that demonstrated that children’s pain as perceived by their focusses on toothache related behaviors such as the Den- parents is correlated with their self-report of pain [6,7]. tal Discomfort Questionnaire. Unfortunately, proxy reports of a child’s pain by their The Dental Discomfort Questionnaire (DDQ) is a be- parents or healthcare provider is often not exact. Both havioral observation tool developed to recognize tooth- over and underestimations of proxy reported pain of ache in children aged 5 years or younger, which focuses children are reported in the literature resulting in sub- on toothache-related pain behaviors [17]. The DDQ was optimal care [8,9]. developed in The Netherlands based on two concepts: 1) Recognizing toothache in preschool children is simi- caries and toothache in young children often results in larly inherently difficult. The tissue damage related to e.g., problems with eating, sleeping and brushing teeth dental caries, which often causes toothache, is not obvi- [15,16] and 2) children’s abilities to verbalize pain de- ous to parents. Consequently, parents regularly do not pends on their developmental cognitive stage [4]. To get realize that their child has a toothache. Furthermore, the an insight into which behaviors children with toothache behavioral expression of children as a result of toothache often display and to see if the presence of these particular is often thought by parents to be related to earache, a behaviors could be used to identify toothache, experienced type of pain that is more familiar to them. Dental caries, dentists interviewed parents of children with toothache to a disease that can result in toothache, however, is one of ask them about the behaviors of their children. These the most prevalent infectious diseases among preschool interviews resulted in a list of 12 behavior items for which children worldwide. For example: a recent study among the prevalence was tested in a group of young children 4-5-year-old Chinese children showed a prevalence of [17]. Eight out of the 12 behaviors in the list were found 72% of caries in primary teeth [10]; among 2-5-year-old to be more often present in children with caries and American children an increase of caries prevalence was toothache than in children without caries and toothache. found from 23% during the period 1998-1994 to 28% Three items concerning earache and one item concerning during the period 1999-2004 [11]; and the last natio- sleeping problems occurred frequently in both groups of nal survey of 5-year-old Brazilian children revealed a children and then were removed [17]. Those 8 items Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 3 of 9 http://www.hqlo.com/content/12/1/30 formed the DDQ. Psychometric properties of the 8-item Participants DDQ tested on preschoolers showed satisfactory internal Participants in this study included 263 children be- consistency (alpha 0.74) [17], as well as toothache predic- tween the ages of 25 and 60 months. Participants were tion ability (ROC area 0.88, CI 0.81-0.94). A score of 3 or approached during public health services for children, higher identified 78.0% of children with toothache in that including hospital outpatient clinics, dental clinics and study [18]. After children undergone dental treatment the day care centers. Children did not have any mental or total score of the DDQ significantly reduced in compari- physical disabilities and cooperated with the dental son with both before and immediately after treatment [19] examination. andafter an8weekfollow-up period [20],further sup- porting the validity of the DDQ. Finally, the developers The instrument: Dental Discomfort Questionnaire - DDQ of the DDQ also developed a version for children with The DDQ is an observational instrument for assessing learning disabilities [21]. Overall, the DDQ can be cate- dental discomfort and/or pain in very young children gorized as an ‘approaching well-establishment’ pain tool [17]. The DDQ contains questions to be completed by a [1,3], but its dimensionality has never been tested child’s parent or caregiver. The respondents were first through factor analysis. asked how often their child had a toothache. Potential To make the DDQ a ‘well-established’ pain tool it is responses included ‘never’, ‘sometimes’, ‘often’ and ‘Ido essential to do additional studies. Exploring the DDQ’s not know’. If s/he noticed that the child had a toothache, dimensionality by means of factor analysis and making the respondent reported when this occurred, i.e., ‘during the DDQ adaptable to different cultures is of particular meals’, ‘during the day’ or ‘during the night’. The second importance in the evidence-based process for improving part of the complete version of the original DDQ includes the instrument establishment [1,3]. Besides, toothache 12 items about different child behaviors that could be assessment studies are relevant because of the known associated with toothache or dental discomfort, which are impact toothache has on preschoolers’ quality of life and answered on a 3-point scale, as follows: 0 ‘never’,1 ‘some- the possible inherent inability of a child in this age group times’,and 2 ‘often’. The twelve items included in the to express it. complete version of the DDQ are as follows: 1. ‘Bites with The aim of this study was to validate a previously cross- molars instead of front teeth’;2. ‘Puts away something nice culturally adapted Brazilian version of the DDQ for caries- to eat’;3. ‘Cries during meals’;4. ‘Has problems with related toothache assessment in Brazilian preschoolers. brushing lower teeth’;5. ‘Has problems with brushing upper teeth’;6. ‘Has earache during the day’;7. ‘Has earache at night’;8. ‘Has earache during eating’;9. ‘Has Materials and methods problems chewing’;10. ’Chews on one side’;11. ‘Reaches The study described in this paper is the second phase of for the cheek while eating’;and 12. ‘Suddenly cries at night’. a larger study. In the first phase described in detail elsewhere (manuscript submitted to publication), the Procedures DDQ with 12-items was cross-culturally translated and The cross-culturally adapted version, which included 12 adapted to be used in Portuguese-Brazil-speaking chil- items, was completed by parents or guardians without dren’s caregivers, according to a universalistic approach interference from the interviewer while their children method [22]. Figure 1 depicts this cross-cultural adapta- had a dental exam. One of three pediatric dentists exam- tion phase, including conceptual and item equivalences, ined children’s dentition status following the World semantic equivalence and operational equivalence. Phase Health Organization (WHO) recommendations [24], after two is related to the measurement and functional equiva- training and calibration. A convenience random sample of lences that are addressed in the current study (validation 14 children was dentally reexamined in a one-week process). The second phase did not involve participants interval by the three pediatric dentists to determine the included in the first phase of this study. intra-examiner agreement. Inter-examiner agreement This study was independently reviewed and approved was measured through pictures: The three pediatric by the Institutional Research Board of the Federal Uni- dentists examined 12 photographs showing teeth of versity of Goias, city of Goiania, State of Goias, Brazil children under 5-years old, for 1 minute and registered (protocol #127/09). Consent was sought from all partici- the affected teeth according to the WHO decayed, pants (parents on behalf of their children): after they un- missing, filled tooth index (dmft) (in lux calibration). derstood the aims, risks, benefits and other characteristics Intra and inter-examiner agreement regarding dmft index of this investigation, they signed a written consent form to were tested with kappa. The intra-examiner kappa varied participate in this study. All phases of this study were done from 0.82 to 0.98 for the three pediatric dentists. Taken in full accordance with ethical principles, including the the dentists’ results in pairs, inter-examiner reliability World Medical Association Declaration of Helsinki [23]. varied from 0.76 to 0.90. Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 4 of 9 http://www.hqlo.com/content/12/1/30 Figure 1 Flowchart of cross-cultural adaptation. Flowchart of the universalistic approach method used to cross-culturally adapt the Dental Discomfort Questionnaire (DDQ), Brazilian-Portuguese version. The examiner used a mouth mirror, a WHO periodon- Statistical analysis tal probe, an artificial LED head lamp (Microdont Star All statistical analyses were carried out using the IBM Light KD 200, Sao Paulo, Brazil) and personal protective Statistical Package for Social Science 19.0 (SPSS Inc., equipment. Children were examined while seated in a Chicago, IL, USA). Statistical significance was set at chair or in their parents’ laps (small children), with the P <0.05. examiner seated in front of the chair. Dentition status was determined using the WHO caries diagnostic criteria Test-retest reliability (dmft index) [24]. Dental codes were written down on a For the test-retest reliability assessment, we calculated spreadsheet by a recording clerk. Children with one or the sample size using the 2 times k formula, where k is more teeth scored as ‘decayed’ or ‘filled with additional the number of points on the scale [25]. As the DDQ decay’ were considered to have decayed teeth. is a three-point scale, k = 3. According to the formula Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 5 of 9 http://www.hqlo.com/content/12/1/30 (2 times “3squared”), a sample of 18 individuals would Exploratory factor analysis and internal consistency be sufficient for this specific test. We included a con- A total of 211 questionnaires were included for explora- venience sample of 38 parents to complete again the tory factor analysis, principal component analysis (PCA) adapted version of the DDQ (with 12-items) one week form. In 52 cases, parents did not complete the 12 items after the first questionnaire was administered. The of the survey; therefore, these questionnaires were ex- test-retest reliability coefficients of each DDQ item cluded from further analysis. The remaining question- were calculated using the weighted-kappa [26]. naires showed good sampling adequacy and sphericity for correlation assessment among the items to proceed with the PCA. Indeed, Bartlett’s Test of Sphericity showed a Exploratory factor analysis and internal consistency significant correlation among items (P < 0.001), and the The dimensionality of the adapted 12-item version was Kaiser-Meyer-Olkin Measure of Sampling Adequacy assessed through exploratory factor analysis: principal (MSA) reached a value of 0.77. component analysis (PCA) form with orthogonal varimax Next, the factors using PCA with orthogonal varimax rotation. Bartlett’s Test was used to assess sphericity and rotation were extracted. Of the 12 possible factors ex- the Kaiser-Meyer-Olkin was used to measure of Sampling tracted, three were considered relevant (Eigenvalues > 1). Adequacy (MSA) [27]. The number of factors in the This model explained 58.2% of the total variance. Table 1 instrument was reduced by using the Kaiser criterion presents the factor loadings for each item after varimax (Eigenvalues over 1.0) [27]. The varimax rotation method rotation. The first factor aggregated items about func- was chosen to minimize the likelihood of two or more sig- tions related to mastication and possible discomfort dur- nificant factors loading for each item by maximizing the ing eating or sleeping and was called the ‘eating and extent to which factors were independent of each other sleeping problems’ domain. The second factor addressed [28]. Item values were retained if they had a primary factor earache, which was reported in different periods; this loading of >0.40 and a secondary factor loading of <0.30 was called the ‘earache problems’ domain. Finally, the [29]. After the PCA, the internal consistency of the differ- third factor focused on problems brushing one’s upper ent factors was assessed using Cronbach’salpha [30]. We or lower teeth and was called the ‘problems with brush- expected to find two factors: one related to earache prob- ing teeth’ domain. lems (3 items) and other comprising the other 9 items. The reliability analysis for each extracted factor showed that the questionnaire with items from the first domain Construct and discriminant validity (‘eating and sleeping problems’) had a good internal Construct validity was tested by associating the median consistency (Cronbach’s alpha coefficient 0.81), while the total score of children with and without parent-reported other two domains had acceptable Cronbach’salpha,0.75 toothache (dichotomized as yes = ‘sometimes’ and ‘often’, and 0.78 respectively (Table 1) [29]. Alpha coefficients and no = ‘never’) (Mann-Whitney U Test) and correlating could not be improved by the exclusion of any item, and it with the number of decayed teeth (Spearman correl- all 12 items had good convergent validity (item scale ation). For discriminant validity, frequencies of the pain- correlation ≥ .40). related behaviors (DDQ items) and the median of DDQ The first factor of DDQ was named DDQ-Brazil total score were compared between four clinical groups of (DDQ-B) and was further explored. The other two factors children, divided accordingly to the occurrence of caries were not considered for the additional analyses. and toothache reported by parents [31]. Construct and discriminant validity analysis of DDQ-B In response to the toothache question, parents reported Results that 46.4% (n = 122) of their children ‘never’ had tooth- Participants ache, 38.4% (n = 101) had such pain ‘sometimes’,9.9% Participants in this study included 263 children, 109 girls (n = 26) had such pain ‘often’, and the parents of 14 and 154 boys, between the ages of 25 and 60 months (5.3%) did not know. Parents of participating children (mean 43.5, SD 9.8), and their parents who completed reported that 42.3% (n = 111) had toothache during eating, the questionnaires. Most questionnaires were filled out 40% (n = 105) had it during the day, and 20% (n = 52) had by mothers (84.8%), followed by fathers (9.5%) and toothache at night. Sixty percent of children had decayed grandmothers (5.7%). teeth (n = 158). Regarding children with reported tooth- ache, parents reported more toothache (‘sometimes’ and Test-retest reliability ‘often’) for children with decayed teeth (n = 112, 88.2%) The test-retest reliability of the 12-item adapted DDQ than for children without decayed teeth (n = 15, 11.8%) using a weighted-kappa for all items showed an excellent (P < 0.001, Chi-square test). Four clinical groups based stability for most items of the instrument (Table 1). on the combination of decayed teeth and toothache Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 6 of 9 http://www.hqlo.com/content/12/1/30 Table 1 Factor loadings after varimax rotation of the three components extracted and results of test-retest reliability for each DDQ item (a) DDQ items Factor 1–‘Eating and Factor 2–‘Earache Factor 3–‘Problems Weighted-kappa coefficient (b) sleeping problems’ problems’ with brushing teeth’ (95% Confidence Interval) Cries during meals 0.79 −0.26 −0.09 0.88 (0.74-1.00) Reaches for the cheek while eating 0.77 0.24 0.06 0.75 (0.55-0.96) Puts away something nice to eat 0.70 0.01 0.16 0.74 (0.52-0.96) Suddenly cries at night 0.60 0.24 0.27 0.84 (0.69-0.98) Chews on one side 0.59 0.28 0.17 0.97 (0.92-1.00) Has problems chewing 0.53 0.20 0.36 0.77 (0.61-0.94) Bites with molars instead of front teeth 0.47 −0.08 0.30 0.68 (0.49-0.88) Has earache during the day 0.04 0.86 0.07 0.80 (0.59-1.00) Has earache at night 0.05 0.75 0.07 0.94 (0.84-1.00) Has earache during eating 0.22 0.72 0.07 0.94 (0.83-1.00) Has problems with brushing lower teeth 0.07 0.09 0.87 0.86 (0.71-1.00) Has problems with brushing upper teeth 0.26 0.11 0.84 0.75 (0.57-0.93) Eigenvalues 4.08 1.62 1.28 % of variance 34.04 13.52 10.67 Cronbach’s alpha coefficient 0.81 0.75 0.78 (a) (b) Items ordered by factor analysis. Test-retest reliability. The numbers in bold refer to the highest factor loading for each item. reported by parents (excluding the questionnaires with related behaviors and the median total DDQ-B scores are the ‘did not know’ marked option for toothache ques- displayed in Table 2 and show the discriminant validity of tion, n = 14) were identified: children with decayed DDQ-B in identifying children with decayed teeth and teeth and toothache (children with caries-related tooth- toothache. The median total DDQ-B score of children ache) (group 1, n = 112); children with decayed teeth with decayed teeth and toothache was higher than the but no toothache (group 2, n = 46); children without median total scores of children included in other groups decayed teeth but with toothache (group 3, n = 15); and (P < 0.001, Mann-Whitney test). Moreover, children with children without decayed teeth or toothache (children decayed teeth and toothache (group 1) exhibited all of the without caries-related toothache) (group 4, n = 76). pain-related behaviors on DDQ-B more often than caries- The median total score on the DDQ-B was 2.0 (first- free children and those without parent-reported toothache third quartile 1.0-5.0), and scores ranged from 0 to 13. (group 4) (P < 0.01, Mann-Whitney test). There was no The children’s ages did not correlate with the total score difference between children with decayed teeth without (Spearman’s rho = 0.08, P = 0.17). Boys had higher me- toothache and children without decayed teeth with tooth- dian total scores (3.0, first-third quartile 1.0-6.0) than ache (groups 2 and 3) in any of the individual items or girls (2.0, first-third quartile 0.5-4.0) (P = 0.01, Mann- median total scores. Whitney test); there were no differences between boys and girls in toothache reported by parents (P = 0.71, Discussion Chi-Square test). The psychometric characteristics of a cross-culturally Children whose parents reported toothache presented adapted version of the Dental Discomfort Questionnaire with higher total DDQ-B scores (median 4.0, first-third (DDQ) to the Brazilian culture were satisfactory. A shorter quartile 2.0-7.0) than those with no toothache (median model of DDQ with 7 items, named DDQ-B, was further 1.0, first-third quartile 0.0-3.0) (P < 0.001, Mann-Whitney explored and validated as a preschooler toothache as- test). Moreover, children with higher DDQ-B scores had a sessment tool, presenting adequate psychometric and higher number of decayed teeth (Spearman’s rho = 0.42, discriminant properties. The ability to discriminate be- P < 0.001). tween the presence and absence of pain is the most The clinical groups (1, 2, 3 and 4) were characterized important quality of any pain assessment measure [32]. by different frequencies of pain-related behaviors (P <0.05, The initial 12-item Brazilian Portuguese adaptation of Kruskal-Wallis test) and different median total DDQ-B the DDQ was found to be a multidimensional instru- scores (P < 0.001, Kruskal-Wallis test). The seven pain- ment with three clearly distinct domains: ‘eating and Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 7 of 9 http://www.hqlo.com/content/12/1/30 Table 2 Frequency of ‘sometimes’ and ‘often’ for each Dental Discomfort Questionnaire–Brazilian version (DDQ-B) item and DDQ-B total scores for different clinical groups Pain-related behaviors from the n (%) DDQ-B (‘sometimes’ and ‘often’) Children with decayed Children with decayed Children without decayed Children without decayed teeth and a toothache teeth without a toothache teethwithatoothache teeth or a toothache a a a,b b Bites with molar instead of front teeth 70 (62.5) 27 (60.0) 8 (53.3) 33 (43.4) a b b b Puts away something nice to eat 58 (51.8) 12 (26.1) 1 (6.7) 12 (15.8) a b b b Crying during meals 68 (60.7) 8 (17.4) 3 (20.0) 10 (13.2) a b b b Problems chewing 61 (54.5) 12 (27.3) 2 (13.3) 11 (14.5) a b b,c c Chewing on one side 54 (61.4) 12 (34.3) 3 (23.1) 10 (15.9) a b b b Reaching for the cheek while eating 68 (60.7) 9 (20.4) 4 (26.7) 8 (10.5) a b b b Suddenly cries at night 64 (57.1) 16 (36.4) 7 (46.7) 21 (27.6) a b b,c c Median total DDQ-B score 5.0 (2.5-7.0) 2.0 (1.0-4.0) 2.0 (1.0-3.5) 1.0 (0-2.0) (first-third quartile) The same letter indicates an insignificant difference, whereas different letters indicate significant differences (P < 0.05) among groups. sleeping problems’, ‘earache problems’ and ‘problems this age range, boys may still be more emotionally ex- with brushing teeth’. Previous study [17] affirmed that pressive than girls; however, at around six years old, the DDQ could be seen as a one-dimensional scale, boys become less likely than girls to express hurt or although that statement was based on its satisfactory distress, as they are made to feel ashamed of their feel- internal consistency only and not on factor analysis. Our ings of weakness [34]. aprioristic expectation of two factors was partially con- One limitation of this study is that the gold standard firmed; however, a third “unexpected” factor included measure of toothache was parental report. This could the two items related to “tooth brushing problems”, and potentially result in an imperfect reference standard we understand that they might be observed in stubborn [35]. To minimize this bias, the occurrence of caries was young children that might have not been in pain. Explor- also assessed and was found to be associated with the ing each factor individually, the ‘eating and sleeping presence of toothache. Parents reported more toothache problems’ domain, which included 7 items, showed the when children had decayed teeth (caries) than when they highest internal consistency. Moreover, this domain on did not. To further eliminate bias for parts of our ana- its own demonstrated a high test-retest reliability, which lysis we chose to exclude the children who had caries supports excellent stability. Together, these findings but for whom the parents indicated they did not have suggest that the 7-item DDQ-B has good psychomet- toothache (possible false negatives) and the children ric properties. The repeated psychometric analyses who did not have caries but for whom the parents indi- described in this study strengthen the properties of cated they did have toothache (possible false positives). the DDQ. Analyses performed in different situations/ A previous cohort study similarly showed that toothache research groups are criteria for a “well-established” is rare in caries-free children but common in children pain assessment tool for use with children in clinical who had caries [13]. The use of different methods in a settings [1,3]. gradual process of validation with confirmation of the Pain-related behaviors are important indicators for the meaning of the analyzed data is recommended [35]. This assessment of pain in preverbal children [6]. As stated in approach was done for construct and discriminant tests our results, pain-related eating and sleeping behaviors in an attempt to improve parent-reported toothache as the gold standard as for very young children, self- were found to be more frequently displayed by children with decayed teeth and toothache than in children who reporting could be misinterpreted [5]. were caries-free and without toothache. In another One way to address the lack of a true gold standard was to conceptualize pain as a latent variable (one that study, it was also found that problems eating certain foods, as reported by parents, were more prevalent in cannot be observed) and use the results of the present young children with decayed teeth than without [15]. exploratory factor analysis to generate hypotheses for confirmatory factor analysis [27,31]. Therefore, further Interestingly, we found that boys had higher DDQ-B scores than girls, but there were no significant sex studies with larger samples should be conducted in the differences found in the incidence of toothache as future to estimate the measurement error when analyz- ing the relationships between DDQ items. reported by parents. This result might be due to the interplay between pain expression, socialization and gen- Furthermore, the item ‘bites with molars instead of der [33]. The presented study focused on preschoolers. In front teeth’ should be viewed with caution, as it does not Daher et al. Health and Quality of Life Outcomes 2014, 12:30 Page 8 of 9 http://www.hqlo.com/content/12/1/30 discriminate between children with toothache. It was Acknowledgements We are grateful to the team, which included graduate and undergraduate kept in the DDQ-B because its removal would not students, of the Pediatric Dental Sedation Clinic (‘Núcleo de Estudos em improve the Cronbach’s alpha. It may be that parents Sedação Odontológica’, NESO) at the Federal University of Goias (UFG) for have difficulties observing whether a child is biting with their support. This research was supported by grants from the Brazilian Federal Agency for Support and Evaluation of Postgraduate Education the front or back teeth. (CAPES), the National Council for Scientific and Technological Development, The DDQ-B offers unique benefits in the assessment Brazil (CNPq), and the Research Foundation of the State of Goias, Brazil of toothache and the subsequent prioritization of dental (FAPEG). treatment among Brazilian children. For the assessment Author details of toothache, there is only one validated Brazilian in- Health Sciences Graduate Program, Federal University of Goias, Goiania, GO, strument (the Child Dental Pain Questionnaire, child- Brazil. Department of Adolescent Medicine, Hospital for Sick Children, University of Toronto, Toronto, ON, Canada. Division of Prosthetic Dentistry, DPQ) with good psychometric properties (ICC = 0.99 Faculty of Dentistry, Federal University of Goias, Goiania, GO, Brazil. Division and Cronbach’s alpha 0.81), but it is used only with of Pediatric Dentistry, Faculty of Dentistry, Federal University of Goias, children between the ages of 8 and 10 years [36]. More- Goiania, GO, Brazil. Faculdade de Odontologia, Primeira Avenida, Setor Universitario, Goiania, GO, Brazil. over, relevant oral health epidemiological data shows children’s need for a validated instrument: more than Received: 6 July 2013 Accepted: 27 February 2014 half of Brazilian children who are 5 years of age and Published: 4 March 2014 under have caries in primary dentition according to a recent national government study [12]. Similar high caries References 1. von Baeyer CL, Spagrud LJ: Systematic review of observational prevalence are found in this age group in Southern (40% (behavioral) measures of pain for children and adolescents aged 3 to 18 of children 0 to 5 years old) [37] and Northern Brazil (62% years. Pain 2007, 127:140–150. of children 2 to 4 years old) [15]. Moreover, 25% of 2. Harbeck C, Peterson L: Elephants dancing in my head: a developmental approach to children’s concept of specific pains. 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Ferreira SH, Béria JU, Kramer PF, Feldens EG, Feldens CA: Dental caries in 0- to 5-year-old Brazilian children: prevalence, severity and associated factors. Int J Paediatr Dent 2007, 17:289–296. doi:10.1186/1477-7525-12-30 Cite this article as: Daher et al.: Screening preschool children with toothache: validation of the Brazilian version of the Dental Discomfort Questionnaire. Health and Quality of Life Outcomes 2014 12:30. Submit your next manuscript to BioMed Central and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color figure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit

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