Training and calibration of interviewers for oral health literacy using the BREALD-30 in epidemiological studies

Periodontitis and non-communicable diseases in a Brazilian population, a cross-sectional study, Vila Velha-ES, Brazil

BACKGROUND

The objective of this study was to examine the hypothesis that periodontal disease is associated with chronic non-communicable diseases.

METHODS

In this cross-sectional study, we evaluated the periodontal health condition of the population, based on the community periodontal index, as well as the number of missing teeth and the presence of systemic health conditions. We quantified the association between oral health and the presence of chronic diseases using simple logistic regression, adjusting for confounding factors including age, smoking, and overweight.

RESULTS

The study population consisted of 334 volunteers, aged between 19 and 81 years. In patients over 45 years old, periodontal disease was found to be significantly associated with hypertension and diabetes. Furthermore, in female patients, periodontal disease was significantly associated with hypertension, diabetes, and cancer.

CONCLUSION

Our findings indicate that periodontal disease is positively and significantly associated with both arterial hypertension and diabetes, independent of potential confounding factors.

An Epistemic Look at Parental Conceptual Knowledge and Oral Health Outcomes in Children

Objective. This study explores the impact of parental oral health knowledge on children's oral health, investigating if limited knowledge contributes to poor outcomes. The CAMBRA caries risk assessment and the World Health Organization dmft/DMFT index measure oral health. Methods. Over 23 months, the Knowledge Related to Oral Health Literacy (KROHL) questionnaire assesses parental knowledge in 4 domains and 5 oral health conditions. Pearson Correlation Coefficient analyzes the association between KROHL scores and CAMBRA outcomes. Results. Positive correlation emerges between parental oral health knowledge levels and children's dental caries risk, indicating the KROHL questionnaire's utility in identifying knowledge gaps. No standardized method for measuring oral health knowledge exists, although various tools claim to address aspects of the issue. This study pioneers the correlation between oral health knowledge and CAMBRA outcomes. Conclusion. The KROHL questionnaire proves a practical, disease-specific tool for research, emphasizing parental oral health knowledge's pivotal role in children's oral health. It serves as a valuable means to identify knowledge gaps and potential areas for intervention and education in oral health.

Structuring of the effects of oral health literacy on dental caries in 12-year-old adolescents

OBJECTIVES

To explore the pathways by which oral health literacy is associated with dental caries in adolescents, assessing direct and indirect effects of family cohesion and socioeconomic status.

METHODS

A population-based, representative cross-sectional study was conducted with 740 12-year-old adolescents in Campina Grande, Brazil. Parents/guardians answered a sociodemographic questionnaire. Adolescents answered validated questionnaires addressing family cohesion and oral health literacy. Dental caries was diagnosed using Nyvad criteria. Two dentists underwent training exercises for the diagnosis and administration of the questionnaires (k > 0.80). Descriptive analysis was followed by the use of structural equation modelling to determine direct and indirect associations between the variables incorporated into the theoretical model of the study (95% CI).

RESULTS

Oral health literacy (standardized coefficient: -3.472, p < .01) and mother's schooling (standardized coefficient: -0.405, p < .01) were directly associated with dental caries, whereas family cohesion and socioeconomic status exerted an indirect effect on the occurrence of dental caries in the adolescents.

CONCLUSIONS

Sociodemographic factors, family characteristics and oral health literary are associated with dental caries in 12-year-old adolescents.

Psychometric properties of an oral health literacy scale for people living with diabetes

This study evaluated the construct validity of the instrument Oral Health Literacy among diabetics. A probabilistic random sample of 239 diabetics from an infinite population answered the 10 items of the questionnaire. The structural validity was assessed by confirmatory factor analysis and goodness of fit, chi-square per degrees of freedom ratio (X2/df), comparative fit index (CFI), goodness-of-fit index (GFI), and root-mean-square error of approximation (RMSEA). Internal consistency was estimated by the average variance extracted (AVE) and composite reliability (CR). The scores were dichotomized with the upper limit of the 95% confidence interval as the cutoff point. The three-dimensional model presented good quality parameters (X2 /df = 2.459; CFI = 0.988; TLI = 0.981) and poor RMSEA (0.078). Internal consistency was adequate; AVE for the Access, Understand/appraise, and Apply subscales were 0.831, 0.981, and 0.954 and the CR for these subscales were 0.893, 0.962, and 0.822, respectively. Inadequate literacy ranged from 41.8 to 48.1%. The three-dimensional model identified (access, understand/appraise, and apply) showed structural validity, good internal consistency, and understandability.

Impact of oral health literacy and psychoactive substances on tooth loss in adolescents

The aim of the present study was to investigate associations between tooth loss, and oral health literacy, the use of multiple psychoactive substances, and the reason for the last dental appointment in adolescents. A cross-sectional study was conducted with a representative sample of 746 adolescents aged 15 to 19 years in Campina Grande, Brazil. Parents/guardians answered a sociodemographic questionnaire. The adolescents answered the Brazilian version of the Rapid Estimate of Adult Literacy in Dentistry (BREALD-30), the Alcohol, Smoking and Substance Involvement Screening Test, and an oral health questionnaire from the National Oral Health Survey. The adolescents were then examined by two examiners who had undergone training and calibration exercises for the diagnosis of tooth loss due to caries (K> 0.80). Associations between variables were investigated using robust logistic regression analysis for complex samples (α = 5%). The prevalence of tooth loss was 17.4%. Oral health literacy (OR = 0.93; 95% CI: 0.89-0.97) was inversely associated with tooth loss, while multiple psychoactive substance use (OR = 2.01; 95% CI: 1.09-3.69) and last dental visit for treatment/symptoms (OR = 3.05; 95% CI: 1.73-5.36) were directly associated with tooth loss. Oral health literacy, multiple psychoactive substance use, and reason for last dental appointment exerted an influence on tooth loss among adolescents.

Contributions of school context to caries on anterior teeth: a multilevel analysis

OBJECTIVE

To investigate whether oral health literacy (OHL) and school context are associated with untreated dental caries on the anterior teeth of adolescents.

METHODS

A representative cross-sectional study was conducted with 746 students aging 15 to 19 in the city of Campina Grande, Brazil. The guardians answered a questionnaire addressing sociodemographic data and the absence/presence of private health insurance. Two examiners were trained for the diagnosis of dental caries using the Nyvad criteria and the measurement of OHL using the Brazilian Rapid Estimate of Adult Literacy in Dentistry (BREALD-30) (Kappa > 0.80). Contextual aspects of the schools were obtained from the 2017 National School Census. Descriptive statistics were conducted, followed by unadjusted and adjusted robust negative binomial regression for complex samples (p < 0.05).

RESULTS

The average number of anterior teeth with untreated caries was 0.95 (SD = 1.77). Among individual factors, the male sex (RR = 1.64; 95%CI: 1.24–2.16), inadequate level of OHL (RR = 2.03; 95%CI: 1.13–1.63), marginal level of OHL (RR = 1.87; 95%CI: 1.05–3.33) and not having private health insurance (RR = 1.34; 95%CI: 1.07–1.68) were associated with untreated caries on anterior teeth. Among school contextual factors, the number of students in the classroom (RR = 2.64; 95%CI: 1.78–3.93), number of public oral health services in the district (RR = 0.14; 95%CI: 0.05–0.39) and average income of the district in which the school is located (RR = 0.99; 95%CI: 0.98–0.99) were associated with the outcome.

CONCLUSIONS

Sociodemographic factors, having private health insurance, OHL, and school context exerted an influence on the occurrence of untreated dental caries on anterior teeth in adolescents aging 15 to 19.

Attention-deficit Disorder, Family Factors, and Oral Health Literacy

Introduction

Relationships amongst attention-deficit/hyperactivity disorder (ADHD), family factors, and oral health literacy (OHL) in adolescents are unclear. The objective of this research was to investigate whether family environment and signs of ADHD are associated with OHL at the onset of adolescence.

Methods

A cross-sectional study was performed with 448 twelve-year-old adolescents enrolled in schools in Cajazeiras, Brazil. Adolescents responded to an instrument measuring OHL (Brazilian version of the Rapid Estimate of Adult Literacy in Dentistry [BREALD-30]) and a validated questionnaire addressing family cohesion and adaptability (Family Adaptability and Cohesion Scales [FACES III]). Parents and teachers answered subscales of the Swanson, Nolan, and Pelham Questionnaire (SNAP-IV) and a socioeconomic questionnaire. Adjusted Poisson regression analysis was employed for the data analysis (P < .05).

Results

Greater OHL was found in adolescents with higher family cohesion scores (rate ratio [RR], 1.02; 95% confidence interval [CI], 1.01–1.03), those whose mothers had more than 8 years of schooling (RR, 1.07; 95% CI, 1.03–1.12), and those whose families earned more than the Brazilian minimum salary (RR, 1.08; 95% CI, 1.03–1.12). Higher family adaptability scores (RR, 0.99; 95% CI, 0.98–0.99) and more signs of ADHD (teachers’ reports) (RR, 0.95; 95% CI, 0.91–0.99) were associated with lower OHL.

Conclusions

OHL in adolescents was influenced by family adaptability and cohesion, signs of ADHD, maternal schooling, and family income.

Family structure, sociodemographic factors and type of dental service associated with oral health literacy in the early adolescence

The aim of this study was to evaluate associations between oral health literacy and family, sociodemographic and dental service characteristics in early adolescents. A cross-sectional study was conducted with 740 schoolchildren. The following variables were investigated using validated questionnaires: oral health literary (BREALD-30), sociodemographic characteristics, type of dental service and family functioning (FACES III). Associations were tested using robust Poisson regression analysis (α=5%). Higher oral health literacy was associated with the female sex (RR=1.09; 95%CI: 1.03-1.14), connected type of family cohesion (RR=1.12; 95%CI: 1.05-1.20), rigid (RR=1.14; 95%CI: 1.04-1.25) and structured (RR=1.11; 95%CI: 1.04-1.20) types of family adaptability, more than eight years of mother's schooling (RR=1.16; 95%CI: 1.10-1.22), age of caregiver more than 38 years (RR=1.07; 95%CI: 1.02-1.13) and the use of private dental services (RR=1.06; 95%CI: 1.01-1.12). The level of oral health literacy in early adolescents was associated with sex, family structure, mother's schooling, caregiver's age and type of dental service used.

Attention-deficit/hyperactivity disorder and oral health literacy exert an influence on the occurrence of dental caries in early adolescence

Little is known regarding the influence of psychosocial factors on dental caries at early adolescence. The study aimed to investigate associations between family environment, attention-deficit/hyperactivity disorder (ADHD) and oral health literacy (OHL) with dental caries experience in early adolescence. A cross-sectional study was conducted with a representative sample of 448 12-year-old adolescents at public and private schools in North-eastern Brazil. Parents/guardians and teachers answered the Brazilian version of the inattention and hyperactivity/impulsivity subscales (SNAP- IV) for the evaluation of ADHD and a sociodemographic questionnaire. An OHL instrument (BREALD-30) and the Family Adaptability and Cohesion Scales (FACES III) were administered to the adolescents. Caries experience (DMFT) was the dependent variable. Data analysis involved Poisson regression with robust variance (α = 5%). Adolescents with more symptoms of ADHD (teachers' reports) (RR: 1.73; 95% CI: 1.31-2.28), those with lower OHL (RR: 1.59; 95% CI: 1.01-2.51), those with a lower family income (RR: 1.38; 95% CI: 1.03-1.83), and those from families with a greater number of residents in the home (RR: 1.18; 95% CI: 1.06-1.31) had greater caries experience. Family adaptability and cohesion were not associated with caries experience. Dental caries experience in early adolescence was influenced by symptoms of ADHD, OHL, and sociodemographic factors.

Family Cohesion Is Associated with the Self-Perceived Need for Dental Treatment among Adolescents

This study explored the association between family cohesion and self-perceived need for dental treatment among adolescents. A school-based representative cross-sectional study was conducted with 746 students aged 15 to 19 randomly selected from schools in Campina Grande, Brazil. Parents/guardians provided information on sociodemographic data, and students completed questionnaires about the self-perceived need for dental treatment, dental pain, and family cohesion and adaptability (FACES III). Two dentists were trained (kappa >0.80) to diagnosis dental caries using the Nyvad criteria and assess adolescents' level of functional oral health literacy (BREALD-30). Descriptive analysis was performed, followed by nonadjusted and adjusted robust binary logistic regression for complex samples (α = 5%). The prevalence of self-perceived need for dental treatment was 88.6%. The presence of dental caries (OR = 2.10; IC 95%: 1.22-3.61), tooth loss (OR = 15.81; IC 95%: 2.14-116.56), dental pain in the last six months (OR = 1.87; IC 95%: 1.06-3.31), and enmeshed family cohesion type (OR = 10.23; IC 95%: 3.96-26.4) remained associated with the self-perceived need for dental treatment in the final model. In conclusion, dental caries, dental pain, tooth loss, and family cohesion influenced the self-perceived need for dental treatment in adolescents.

Contextual and individual factors associated with oral health literacy in adolescents: A multi-level approach

This study aimed to evaluate the association of contextual and individual factors with Oral Health literacy (OHL) in early adolescence. This is a population-based cross-sectional study carried out with 740 12-year-old adolescents randomly selected by a two-stage probabilistic cluster sampling process from schools in Campina Grande, Brazil. The guardians provided sociodemographic information. Adolescents answered the Brazilian version of the Family Adaptability and Cohesion Scales (FACES III) to measure family functioning, and the Brazilian Rapid Estimate of Literacy in Dentistry (BREALD-30) to measure OHL. Descriptive analysis was conducted, followed by robust Poisson's regression analysis for complex samples with a multilevel approach (p<0.05). Rate ratio (RR) and 95% confidence intervals (CI) were calculated. The two levels of the analysis were students and schools. Adolescents enrolled at schools with higher grade-retention rate had slightly worse OHL scores (RR = 0.99; 95% CI: 0.98 to 0.99). The following individual factors were associated with the level of OHL: the female sex (RR = 1.05; 95% CI: 1.01 to 1.10), mother's schooling more than eight years (RR = 1.13; 95% CI: 1.08 to 1.19), younger guardians (RR = 0.94; 95% CI: 0.90 to 0.97) and a balanced family functioning (RR = 1.08; 95% CI: 1.01 to 1.14). Individual and contextual factors were associated with OHL in early adolescence.

Family cohesion and attention deficit exert an influence on visits to the dentist in early adolescence

OBJECTIVES

To determine whether family environment, signs of attention deficit/hyperactivity disorder (ADHD) and oral health literacy (OHL) are associated with visits to the dentist in adolescents.

METHODS

A school-based cross-sectional study was conducted with a representative sample of 448 12-year-old adolescents enrolled at schools in the city of Cajazeiras, Brazil. The adolescents answered a validated questionnaire addressing family cohesion and adaptability (FACES III), an OHL measure (Brazilian Rapid Estimate of Adult Literacy in Dentistry [BREALD-30]) and a questionnaire addressing the history of visits to the dentist and previous toothache experience. The parents answered a questionnaire addressing sociodemographic characteristics. Parents and teachers answered the inattention and hyperactivity/impulsivity subscales of the Swanson, Nolan & Pelham (SNAP-IV) questionnaire for the detection of signs of ADHD. Multiple Poisson regression with robust variance was used for data analysis (α = 5%).

RESULTS

The prevalence of having visited a dentist some time in life was higher among adolescents with enmeshed (PR = 1.08; 95% CI: 1.01-1.15) and connected (PR = 1.06; 95% CI: 1.01-1.13) families and those with attention deficit according to parents' reports (PR = 1.09; 95% CI: 1.04-1.14). A family income higher than the Brazilian minimum wage (PR = 1.06; 95% CI: 1.01-1.12) and toothache in the previous six months (PR = 1.05; 95% CI: 1.01-1.11) were also associated with the outcome.

CONCLUSION

Family cohesion and attention deficit according to parental reports influenced visits to the dentist among adolescents. In contrast, OHL was not associated with the outcome.

Association of Oral Health Literacy and School Factors with Untreated Dental Caries among 12-Year-Olds: A Multilevel Approach

Dental caries are a global health problem that affects all age groups and must be considered a public health priority due to its significant financial costs and impact on the quality of life. This study evaluated the association between oral health literacy (OHL), school factors, and untreated dental caries in 12-year-old Brazilian adolescents using a multilevel approach. A population-based cross-sectional study was carried out with 740 adolescents randomly selected from private and public schools in Campina Grande, Brazil. Two dentists were trained and calibrated to diagnose dental caries using the Nyvad index and OHL using the Brazilian Rapid Estimate of Literacy in Dentistry (BREALD-30). The caregivers of the adolescents reported demographic data (sex, skin color, and socioeconomic status). Data of school factors such as the type of school and the school grade retention rate were classified through a 2-step hierarchical cluster analysis to obtain the school environment. A robust multilevel log-linear negative binomial regression for complex samples was performed (p < 0.05). In the analysis, adjusted by individual determinants, nonwhite skin color (RR = 2.20; 95% CI 1.56-3.12), a low socioeconomic status (RR = 1.60; 95% CI 1.09-2.34), a low OHL score (RR = 0.94; 95% CI 0.91-0.98), and low satisfaction with the last dental appointment (RR = 2.25; 95% CI 1.67-3.04) were associated with untreated dental caries. The following factors remained associated with untreated dental caries in the final model: students from an unfavorable learning environment (RR = 2.20; 95% CI 1.27-3.80), nonwhite skin color (RR = 1.92; 95% CI 1.27-2.91), a low socioeconomic status (RR = 1.82; 95% CI 1.12-2.94), a low OHL score (RR = 0.95; 95% CI 0.91-0.98), and low satisfaction with the last dental appointment (RR = 2.07; 95% CI 1.47-2.91). Untreated dental caries in early adolescence were impacted by the school environment, the socioeconomic status, OHL, and the adolescent's satisfaction with the last dental appointment.

Oral health literacy, sociodemographic, family, and clinical predictors of dental visits among Brazilian early adolescents

BACKGROUND

The prevalence of dental caries is high in adolescents worldwide, and a large percentage have never been to a dentist or have not had regular dental appointments.

AIM

To evaluate the influence of oral health literacy and sociodemographic, clinical, and family factors on dental visits among early adolescents.

DESIGN

A cross-sectional study was conducted with 740 12-year-old students in Campina Grande, Brazil. Students answered about their level of oral health literacy (BREALD-30), levels of family adaptability and cohesion (FACES III), and visits to the dentist sometime in life. Dental caries experience was evaluated using Nyvad criteria. Robust Poisson regression for complex samples was performed.

RESULTS

A higher level of oral health literacy (PR = 1.01; 95% CI: 1.01-1.03), high social class (PR = 1.28; 95% CI: 1.09-1.50), higher mother's schooling (PR = 1.58; 95% CI: 1.37-1.83), family cohesion classified as enmeshed (PR = 1.55; 95% CI: 1.19-2.02) and connected (PR = 1.22; 95% CI: 1.02-1.44), and the absence of toothache (PR = 1.18; 95% CI: 1.01-1.38) remained associated with having visited a dentist.

CONCLUSIONS

Oral health literacy and sociodemographic, family, and clinical factors were predictors of having visited a dentist among early adolescents.

Socioeconomic status and family functioning influence oral health literacy among adolescents

OBJECTIVE

Evaluate socio-demographic, family and behavioral factors associated with oral health literacy (OHL) in adolescents.

METHODS

Cross-sectional study conducted with adolescents aged 15 to 19 years in Campina Grande, Brazil. Parents/guardians answered a questionnaire addressing socio-demographic data. The adolescents answered validated instruments on family cohesion and adaptability (family adaptability and cohesion evaluation scale), drug use (alcohol, smoking and substance involvement screening test), type of dental service used for last appointment and OHL (Brazilian version of the Rapid Estimate of Oral Health Literacy in Dentistry). Two dentists were trained to evaluate OHL (K = 0.87-0.88). Descriptive analysis was performed, followed by Poisson regression analysis (α = 5%). A directed acyclic graph was used to select independent variables in the study.

RESULTS

The following variables remained associated with better OHL: high mother's schooling level (RR = 1.07; 95%CI: 1.03-1.12), high income (RR = 1.04; 95%CI: 1.01-1.09), white ethnicity/skin color (RR = 1.05; 95%CI: 1.01-1.10), married parents (RR = 1.04; 95%CI: 1.01-1.09), "enmeshed" family cohesion (RR = 1.21; 95%CI: 1.12-1.30), "structured" (RR = 1.06; 95%CI: 1.01-1.12) or "rigid" (RR = 1.11; 95%CI: 1.04-1.19) family adaptability, having more than five residents in the home (RR = 1.07; 95%CI: 1.01-1.14) and having used a private dental service during the last appointment (RR = 1.08; 95%CI: 1.03-1.13).

CONCLUSION

Family functioning and socio-demographic factors influence the level of oral health literacy among adolescents.

Adolescents with worse levels of oral health literacy have more cavitated carious lesions

The aim of the present study was to investigate whether the ability to recognize and read oral health terms is associated with the number of teeth with cavitated carious lesions in adolescents. A population-based cross-sectional study was conducted involving a sample of 746 adolescents representative of students aged 15 to 19 years at the public and private school systems in a city in northeast Brazil. Two examiners who had undergone a training and calibration exercise (inter-examiner and intra-examiner Kappa coefficient: 0.87 to 0.93) performed the diagnosis of caries using the Nyvad Index and evaluated the level of OHL (BREALD-30) of the adolescents. The participants answered questions regarding their history of visits to the dentist and the parents/caregivers answered a questionnaire addressing socioeconomic characteristics. A directed acyclic graph was created to direct the selection of covariables for adjustments in the Poisson multiple regression analysis to test the association between dental caries and OHL (α = 5%). Cavitated carious lesions (codes 3 to 6 on the Nyvad index) were found in 41.6% of the adolescents. Only 29.4% had a high level of OHL (BREALD-30 scores between 23 and 30); 42.3% of the families belonged to the A-B social class and 93% of the adolescents had been to the dentist at least once in their lifetimes. In the multivariate analysis, adolescents with inadequate (PR: 1.69; 95% CI: 1.18–2.41; p = 0.004) and marginal (PR; 1.42; 95% CI: 1.01–1.99; p = 0.042) OHL and those in the lower social classes (C-D-E) (PR: 1.85; 95% CI: 1.39–2.47; p<0.001) had more teeth with cavitated carious lesions. In conclusion, adolescents aged 15 to 19 years with poorer levels of OHL had a larger number of teeth with cavitated carious lesions, independently of their socioeconomic status and history of visiting a dentist.

Psychometric properties of BREALD-30 for assessing adolescents' oral health literacy

OBJECTIVE

To evaluate the psychometric properties of the Brazilian Portuguese version of the Rapid Estimate of Adult Literacy in Dentistry (BREALD-30) administered to adolescents.

METHODS

The study included 750 adolescents: 375 aged 12 years and 375 aged 15–19 years, attending public and private schools in Campina Grande, state of Paraíba, Brazil, in 2017. Reliability was measured based on internal consistency and test-retest reliability. Convergent validity was measured based on correlations between BREALD-30 and Functional Literacy Indicator scores. Divergent validity was measured by comparing BREALD-30 scores with sociodemographic variables. For predictive validity, the association between BREALD-30 scores and the presence of cavitated carious lesions was tested using a multiple logistic regression model. All statistical tests were performed with a significance level of 5%.

RESULTS

BREALD-30 showed good internal consistency for the 12 year olds and 15 to19 year olds (Cronbach’s alpha = 0.871 and 0.834, respectively) and good test-retest reliability [intraclass correlation coefficient (ICC) = 0.898 and 0.974; kappa = 0.804 and 0.808, respectively]. Moreover, item-total correlation was satisfactory for all items. BREALD-30 had convergent validity with the Functional Literacy Indicator for 12 year olds (rs = 0.558, p < 0.001) and for 15 to 19 year olds (rs = 0.652, p < 0.001). Participants with higher oral health literacy levels who attended private schools (p < 0.001), belonged to economic classes A and B2 (p < 0.001), and who had parents with higher education levels (p < 0.001) were included, indicating the divergent validity of the BREALD-30. Participants with lower BREALD-30 scores were more likely to have cavitated carious lesions [12 year olds: odds ratio (OR) = 2.37; 95% confidence interval (95%CI): 1.48–3.80; 15 to 19 year olds: OR = 1.96; 95%CI 1.24–3.11].

CONCLUSIONS

BREALD-30 shows satisfactory psychometric properties for use on Brazilian adolescents and can be applied as a fast, simple, and reliable measure of oral health literacy.

Caregiver’s oral health literacy is associated with prevalence of untreated dental caries in preschool children

Abstract The aim of this study was to evaluate the relationship between oral health literacy (OHL) among caregivers and untreated dental caries among preschoolers. A cross-sectional study was conducted involving 415 preschool children and their caregivers from Curitiba, Brazil. The children were examined for dental caries and dental plaque. The caregivers’ OHL was evaluated using an instrument translated and validated for Brazilian Portuguese: the Brazilian Rapid Estimate of Adult Literacy in Dentistry-30. The prevalence of children with untreated caries was 42.9% (95%CI: 38.1-47.7%). A low degree of OHL was found among 15.7% (95%CI: 12.2-19.2) of caregivers. The multivariable Poisson regression analysis indicated a higher prevalence of untreated caries among children whose caregivers had a low OHL (PR = 1.35; 95% CI: 1.01-1.79), those with visible plaque (PR = 1.28; 95% CI: 1.01-1.62) and those who never or only occasionally had their teeth brushed by their caregivers (PR = 1.48; 95% CI: 1.16-1.91) in comparison to those without these conditions. In conclusion, a higher prevalence of untreated dental caries was found among preschool children whose caregivers had a low degree of OHL.

Impact of oral health literacy on self-reported missing data in epidemiological research

OBJECTIVES

To investigate whether oral health literacy (OHL) impacts missing data obtained through self-reporting in oral health epidemiological research.

METHODS

A cross-sectional study was conducted with parents (n = 344) of 4- to 5-year-old children randomly selected from public schools within the city of Curitiba, Brazil. Parental OHL was measured using the Brazilian version of the Rapid Estimate of Adult Literacy in Dentistry (BREALD-30). Parents answered a set of questionnaires comprising 88 items concerning sociodemographic and economic data, children's access to dental services, oral hygiene behaviour, diet and mealtime behaviour. The total number of unanswered items (TUI) and the number of unanswered items in each type of question (open-ended, dichotomous, multiple choice with up to 4 options and with 5-9 options) for each participant was compared across different levels of OHL (chi-squared, Mann-Whitney, Kruskal-Wallis and Spearman's correlation test). Multiple Poisson regression was used to estimate rate ratios (RR) of TUI between OHL scores and their respective 95% confidence interval (95% CI).

RESULTS

Approximately one-third of studied parents (37%) exhibited low OHL (BREALD-30 ≤ 21). The prevalence of missing data in at least one item was 85.5%. Low OHL was associated with failing to respond open-ended items (P = 0.003) and multiple-choice items with up to 4 (P = 0.003) and between 5 and 9 options (P = 0.030). There was a negative correlation between OHL scores and TUI (r = -0.195; P < 0.001), as well as with the number of unanswered items in all types of questions (P < 0.01), except dichotomous questions. Parents with lower OHL were more likely to show higher values of TUI (RR 0.95: 0.93-0.98), when adjusted by income and education.

CONCLUSIONS

Participants with lower OHL were significantly more likely to fail to complete research questionnaires. The impact of OHL on missing data was greater with more complex types of items.