Abstract
Objective: The aim of the present study was to evaluate the influence of oral conditions in preschool children and associated factors on work absenteeism experienced by parents or guardians. Methods: A preschool-based, cross-sectional study was conducted of 837 children, 3–5 years of age, in Campina Grande, Brazil. Parents or guardians answered the Brazilian version of the Early Childhood Oral Health Impact Scale. The item ‘taken time off work’ was the dependent variable. Questionnaires addressing sociodemographic variables, history of toothache and health perceptions (general and oral) were also administered. Clinical examinations for dental caries and traumatic dental injury (TDI) were performed by three dentists who had undergone training and calibration exercises. Cohen’s kappa (κ) was 0.83–0.88 for interexaminer agreement and 0.85–0.90 for intra-examiner agreement. Descriptive, analytical statistics were conducted, followed by logistic regression for complex samples (α = 5%). Results: The prevalence of parents’ or guardians’ work absenteeism because of the oral conditions of their children was 9.2%. The following variables were significantly associated with work absenteeism: mother’s low schooling [odds ratio (OR) = 2.31; 95% confidence interval (95% CI): 1.31–4.07]; history of toothache (OR = 6.33; 95% CI: 3.18–12.61); and avulsion or luxation types of TDI (OR = 8.54; 95% CI: 1.80–40.53). Conclusion: Other oral conditions that do not generally cause pain, such as dental caries with a low degree of severity or inactive dental caries and uncomplicated TDI, were not associated with parents’ or guardians’ work absenteeism of preschool children. It is concluded that toothache, avulsion, luxation and a low degree of mother’s schooling are associated with work absenteeism.
Key words: Absenteeism, work, parents, child preschool, dental caries, tooth injuries
INTRODUCTION
Despite increased access to public health-care services in Brazil in recent years1, there continues to be a large number of preschool children with dental caries and traumatic dental injury (TDI)2., 3.. These conditions can exert an influence on functional, emotional and social aspects, thereby impacting oral health-related quality of life (OHRQoL)4., 5..
Preschool children in need of dental treatment depend on parents or guardians to accompany them to the dentist, which affects family functioning as a result of missed days of work and the possible loss of income6. Research has tended to focus on the benefits or effectiveness of treatment7. The ability to define and interpret social aspects linked to the search for dental treatment are less-understood or less-studied aspects of oral health. Access to care may depend significantly on factors such as the availability of transportation, access to childcare and the opportunity to take time away from work8. Indeed, the social cost of adverse health conditions on daily living includes time away from work, school and normal activities. A previous study found that more than 40 million hours are lost annually because of oral conditions, resulting in potential losses in productivity of more than US$1 billion9. The main factors influencing total cost are the number of visits and severity of the injury10.
A number of studies have addressed work absenteeism rates caused by oral conditions in adults11., 12., 13., 14., whereas studies addressing work absenteeism of parents because of the oral conditions of their children have been restricted to non-dental causes15., 16.. Although oral conditions in preschool children can result in work absenteeism of their parents or guardians, previous studies have only reported the frequency of missed work days5., 17., 18., 19.. To the best of our knowledge, the present investigation is the first study to analyse factors associated with work absenteeism as a result of oral conditions in preschool children and the treatment of such problems. This information is essential for understanding the impact of oral conditions at the societal level and evaluating oral health policies, especially regarding the economic aspects involved in this process9., 20..
The aims of the present study were to evaluate the prevalence of negative impact on family functioning stemming from parents’ or guardians’ work absenteeism because of the oral conditions of their children and to evaluate the influence of oral conditions in preschool children and associated factors on work absenteeism in a preschool-based sample selected using a multistage sampling process.
METHODS
Ethical considerations
The Institutional Review Board of the State University of Paraíba (Brazil) granted approval for the present study (process number: 00460133000-11) in compliance with Resolution 196/96 of the Brazilian National Health Council. This study was conducted in full accordance with the Declaration of Helsinki of the World Medical Association, and all participants’ rights were protected. Moreover, the parents or guardians signed a statement of informed consent to allow the children to participate.
Sample characteristics
A cross-sectional study was conducted involving a random sample of 837 male and female children, 3–5 years of age, enrolled at private and public preschools in the city of Campina Grande, an industrialised city in north-eastern Brazil. The participants were selected from a total population of 12,705 children in this age group. Campina Grande has a population of 386,000 and is divided into six administrative districts. The human development index for this city is 0.7221.
The percentage distribution of 3- to 5-year-old preschool children in each administrative district was calculated from information provided by the municipal Board of Education. The sample was stratified, according to administrative district and type of institution (using a two-phase sampling method), to ensure representativeness. In the first phase, preschools were randomly selected from each administrative district. After this phase, preschool children were randomly selected from each preschool. The ratio of the total population enrolled in private and public preschools in each administrative district of the city was maintained in the sample distribution.
The sample size was estimated based on the different predicted outcomes in this study, the prevalence of absenteeism among parents or guardians as a result of the oral conditions of their children and associated factors. Thus, the decision was made to consider the largest sample required, which was calculated based on the prevalence of absenteeism. The parameters of a 4% margin of error, a 95% confidence level and a correction factor of 1.2 to compensate for the design effect were utilised to calculate the sample size. Moreover, a 50% prevalence rate of negative impact on family functioning, stemming from work absenteeism of parents or guardians because of the oral conditions of their children, was considered to increase the power, as this value gives the largest sample regardless of the actual prevalence22. Eighteen of the 127 public preschools and 15 of the 122 private preschools were randomly selected. A group of 720 preschool children was estimated as the minimum sample size, to which an additional 20% was added to compensate for possible losses, giving a total of 864 preschool children.
Eligibility criteria
The eligibility criteria were children between 3 and 5 years of age who were enrolled at a preschool, were in the primary dentition phase and were free of systemic diseases. No systemic examination was conducted; only the reports of parents or guardians were considered with regard to the absence or presence of systemic diseases. The exclusion criteria were a history of orthodontic treatment and parents or guardians who were not fluent in Brazilian Portuguese.
Training and calibration exercises
The training and calibration exercises consisted of two steps (theoretical and clinical). For the theoretical step, a discussion was held on the criteria for the diagnosis of dental caries and TDI. A gold-standard specialist in paediatric dentistry coordinated this step, instructing three general dentists on how to perform the examination. The clinical step was conducted at a randomly selected preschool that was not part of the main sample. A total of 50 preschool children, between 3 and 5 years of age, were examined by each dentist. A tooth-by-tooth basis was utilised for data analysis through Cohen’s kappa (κ) coefficient. Interexaminer agreement was tested by comparing each examiner with the gold standard (κ = 0.83–0.88) for dental caries and TDI. After a 7-day interval, clinical examinations were conducted to determine intra-examiner agreement (κ = 0.85–0.90) for dental caries and TDI. The examiners were considered capable of performing the epidemiological study based on the high κ coefficients23. The preschool children examined in the calibration exercises did not participate in the main study.
Pretesting of questionnaire
A pilot study, using a convenience sample of 40 preschool children, was carried out. This research stage was conducted to test the methodology and subjects’ comprehension of the questionnaires. These preschool children were not included in the main sample. No changes to the data-collection process were deemed necessary because there were no misunderstandings regarding the questionnaires or the methodology.
Non-clinical data collection
The collection of non-clinical data involved one item on the family function subscale of the Brazilian version of the Early Childhood Oral Health Impact Scale (B-ECOHIS) and questionnaires addressing sociodemographic data, health perceptions and history of toothache. Parents were sent a letter via the preschool explaining the aims of the study along with the statement of informed consent and questionnaires. Parents who signed the statement of informed consent and completed the questionnaires were included in the study. The parents or guardians were instructed to consider the child’s lifetime experience of oral conditions and treatment for the answers of the B-ECOHIS. This study followed the same methodology used in previous studies4., 24., 25., 26..
The B-ECOHIS addresses the perceptions of parents or guardians regarding the impact of oral conditions on the quality of life of preschool children and their families. This scale is divided into two sections (Child Impact and Family Impact) containing six subscales and 13 items. The impact on parents’ or guardians’ work absenteeism was evaluated using the family function subscale27., 28.. The item ‘How often have you or another family member taken time off from work because of your child’s dental problems or treatments?’ has demonstrated satisfactory internal consistency and reliability. For statistical purposes, this item was dichotomised as absent (corresponding to the response option ‘never’) or present (corresponding to the remaining response options: ‘hardly ever’, ‘sometimes’, ‘often’ and ‘very often’). ‘Don’t know’ responses were not counted.
Five sociodemographic variables were collected: child’s sex; child’s age; mother’s schooling; age of parent or guardian; and household income (classified based on the monthly minimum wage in Brazil at the time of collection, which was equal to US$312.50).
The parent’s or guardian’s perceptions regarding their child’s general and oral health status were evaluated through a question proposed in a previous study. The following question: ‘In general, how would you describe your child’s general health/oral health?’ was evaluated18 The answer was scaled according to the following codes: 1, very good; 2, good; 3, fair; 4, poor; and 5, very poor. In the statistical analysis, the codes were dichotomised as good (codes 1 and 2) or poor (codes 3, 4 and 5).
Clinical data collection
The clinical examinations were performed, after the return of the statement of informed consent and the questionnaires, by three dentists who had undergone the training and calibration exercise. Before the clinical examinations, each child received a kit containing a toothbrush, toothpaste and dental floss. Under the supervision of the examiner, all children cleaned their teeth using the products in this kit. This procedure removed bacterial plaque from the tooth surfaces and facilitated the diagnosis. The dentists used individual protection equipment, a sterile mouth mirror (PRISMA®, São Paulo, SP, Brazil), a sterile Williams probe (WHO-621; Trinity®, Campo Mourão, PA, Brazil) and dental gauze to dry the teeth. For clinical examinations, the children were examined at their preschool in a sitting position in front of the examiner. Lighting was provided by a portable headlamp (Petzl Zoom head lamp; Petzl America, Clearfield, UT, USA).
The International Caries Detection and Assessment System (ICDAS II) was used for the diagnosis of dental caries29. This index has codes ranging from 0 (absence of dental caries) to 6 (high-severity caries). Code 1 was not used (because of the epidemiological nature of the present study) as drying of the teeth was performed with gauze rather than with compressed air. Code 2 is used for white spots, and codes ≥ 3 determine different degrees of cavitation. Low-severity caries was indicated by codes 3 and 4, whereas codes 5 and 6 indicated high-severity caries29.
The clinical examination of TDI used a classification system with the following types of TDI: enamel fracture; enamel and dentin fracture; complicated crown fracture; extrusive luxation; lateral luxation; intrusive luxation; and avulsion30. Moreover, a visual evaluation of tooth colour was performed. Tooth discoloration, as a result of the occurrence of TDI, was confirmed with the report of the parent or guardian. In analysing the data, TDI was recorded as present when any type of injury or tooth discoloration was diagnosed.
A fluoridated varnish was applied to all teeth after the examination. According to necessity, children with dental caries or other dental needs were sent for treatment.
Statistical analysis
Initially, descriptive statistics were used for characterisation of the sample. The frequency distribution of the data was determined. Work absenteeism experienced by parents or guardians because of the oral conditions of their children (dichotomised as ‘yes’ or ‘no’) was the dependent variable. Logistic regression, considering the design effect in sampling weights for complex samples, was conducted for each dependent variable (P < 0.05). Each preschool received a sample weight. The sample weight considered the number of preschools selected for the study, the total number of preschools of the city, the number of children enrolled in the preschool that participated in the study and the total number of children enrolled in preschool (this parameter was used for each preschool, either public or private). The sample weight was inserted in the statistical program and was included on the sampling plan to run the logistic regression analysis31. In the multiple logistic regression model, independent variables with P <0.20 were incorporated using the backward stepwise procedure. In carrying out this step of the study, the Statistical Package for Social Sciences (SPSS for Windows, version 18.0; SPSS Inc., Chicago, IL, USA) was used.
RESULTS
A total of 837 preschool children, paired with their parent or guardian, participated in the study, which corresponds to 96.8% of the total determined during the calculation of the sample size. The loss of 27 pairs was because of a lack of cooperation on the part of the child during the clinical examination (n = 6), incomplete questionnaires (n = 11), absence from preschool on the days scheduled for the clinical examination (n = 4) and ‘don’t know’ responses on the B-ECOHIS item addressing work absenteeism (n = 6).
Table 1 displays the sociodemographic and clinical characteristics of the sample. Most children (65.9%) did not exhibit TDI. However, 66.5% were diagnosed with dental caries (white spot or cavitation). A total of 9.2% of the parents or guardians reported a negative impact on family functioning stemming from work absenteeism because of the oral conditions of their children.
Table 1.
Sociodemographic and clinical characteristics of the sample
| Variable | Frequency |
|
|---|---|---|
| n | % | |
| Sex | ||
| Male | 432 | 51.6 |
| Female | 405 | 48.4 |
| Age | ||
| 3 years | 274 | 32.7 |
| 4 years | 332 | 39.7 |
| 5 years | 231 | 27.6 |
| Mother’s schooling | ||
| ≤8 years of study | 384 | 46.0 |
| >8 years of study | 450 | 54.0 |
| Household income* | ||
| ≤1 monthly minimum wage | 437 | 54.8 |
| >1 monthly minimum wage | 361 | 45.2 |
| Dental caries | ||
| Absent | 280 | 33.5 |
| Present | 557 | 66.5 |
| TDI** | ||
| Absent | 549 | 65.9 |
| Present | 284 | 34.1 |
| Work absenteeism | ||
| Absent | 760 | 90.8 |
| Present | 77 | 9.2 |
| Total | 837 | 100.0 |
Thirty-nine interviewees did not provide this information.
n < 837 for traumatic dental injury (TDI) (n = 833) as a result of tooth loss and/or destruction that rendered the diagnosis impossible.
In the bivariate analysis, the following independent variables were associated with work absenteeism: mother’s schooling ≤8 years; household income lower than the Brazilian monthly minimum wage; the parent’s or guardian’s perception of their child’s oral health status as poor; a history of toothache; dental caries; and high-severity dental caries (Table 2). Table 3 displays the results of the multiple logistic regression. The variables that remained in the final model were mother’s low schooling [odds ratio (OR) = 2.31; 95% confidence interval (95% CI): 1.31–4.07], history of toothache (OR = 6.33; 95% CI: 3.18–12.61) and avulsion or luxation types of TDI (OR = 8.54; 95% CI: 1.80–40.53).
Table 2.
Bivariate logistic regression for complex samples regarding work absenteeism and independent variables among children 3–5 years of age
| Variable | Work absenteeism |
P-value | Bivariate |
Size effect | |
|---|---|---|---|---|---|
| Yes n (%) | No n (%) | Unadjusted OR(95% CI) | |||
| Sex | |||||
| Male | 46 (10.6) | 386 (89.4) | 1.00 | 0.05 | |
| Female | 31 (7.7) | 374 (92.3) | 0.249 | 1.36 (0.81–2.28) | |
| Age of child | |||||
| 3 years | 22 (8.0) | 252 (92.0) | 0.385 | 0.75 (0.40–1.43) | 0.05 |
| 4 years | 27 (8.1) | 305 (91.9) | 0.584 | 1.19 (0.63–2.25) | |
| 5 years | 28 (12.1) | 203 (87.9) | 1.00 | ||
| Mother’s schooling | |||||
| ≤8 years of study | 49 (12.8) | 335 (87.2) | <0.001 | 2.67 (1.58–4.52) | 0.11 |
| >8 years of study | 28 (6.2) | 422 (93.8) | 1.00 | ||
| Household income | |||||
| ≤1 monthly minimum wage | 50 (11.4) | 387 (88.6) | 0.006 | 2.13 (1.24–3.65) | 0.07 |
| >1 monthly minimum wage | 26 (7.2) | 335 (92.8) | 1.00 | ||
| Age of parent or guardian | |||||
| ≤30 years | 36 (8.6) | 383 (91.4) | 0.812 | 1.06 (0.64–1.78) | 0.02 |
| >30 years | 39 (9.8) | 361 (90.2) | 1.00 | ||
| Perception of general health | |||||
| Good | 57 (8.4) | 619 (91.6) | 1.00 | 0.05 | |
| Poor | 19 (12.1) | 138 (87.9) | 0.202 | 1.47 (0.81–2.68) | |
| Perception of oral health | |||||
| Good | 34 (6.1) | 525 (93.9) | 1.00 | 0.15 | |
| Poor | 43 (15.5) | 234 (84.5) | <0.001 | 2.74 (1.64–4.57) | |
| Toothache | |||||
| Absent | 26 (4.7) | 532 (95.3) | 1.00 | 0.30 | |
| Present | 50 (18.9) | 215 (81.1) | <0.001 | 6.44 (3.81–10.88) | |
| Dental caries | |||||
| Absent | 16 (5.7) | 264 (94.3) | 1.00 | 0.08 | |
| Present | 61 (11.0) | 496 (89.0) | 0.039 | 1.91 (1.03–3.52) | |
| Severity of dental caries | |||||
| Absent | 16 (5.7) | 264 (94.3) | 1.00 | 0.14 | |
| White spot | 7 (4.4) | 151 (95.6) | 0.600 | 0.77 (0.29–2.04) | |
| Low severity cavitations | 7 (10.1) | 62 (89.9) | 0.379 | 1.57 (0.57–4.30) | |
| High severity cavitations | 47 (14.2) | 283 (85.8) | 0.003 | 2.61 (1.38–4.94) | |
| TDI | |||||
| Absent | 50 (9.1) | 499 (90.9) | 1.00 | <0.01 | |
| Present | 25 (8.8) | 259 (91.2) | 0.522 | 0.84 (0.49–1.44) | |
| Type of TDI | |||||
| Enamel fracture and without trauma | 58 (8.5) | 627 (91.5) | 1.00 | 0.05 | |
| Enamel + dentin fracture | 3 (7.1) | 39 (92.9) | 0.694 | 0.77 (0.22–2.78) | |
| Avulsion or luxation (or both) | 3 (27.3) | 8 (72.7) | 0.024 | 5.28 (1.24–22.47) | |
| Discoloration | 11 (11.6) | 84 (88.4) | 0.540 | 1.26 (0.60–2.66) | |
95% CI, 95% confidence interval; OR, odds ratio; TDI, traumatic dental injury.
Table 3.
Multiple logistic regression for complex samples regarding work absenteeism and independent variables among children 3–5 years of age
| Variable | P-value | Multiple |
Size effect |
|---|---|---|---|
| Adjusted OR (95% CI)* | |||
| Mother’s schooling | |||
| ≤8 years of study | 0.004 | 2.31 (1.31–4.07) | 0.11 |
| >8 years of study | 1.00 | ||
| Toothache | |||
| Yes | <0.001 | 6.33 (3.18–12.61) | 0.30 |
| No | 1.00 | ||
| Type of TDI | |||
| Enamel fracture and without trauma | 1.00 | 0.05 | |
| Enamel + dentin fracture | 0.989 | 1.01 (0.27–3.72) | |
| Avulsion or luxation (or both) | 0.007 | 8.54 (1.80–40.53) | |
| Discoloration | 0.854 | 1.08 (0.48–2.40) | |
95% CI, 95% confidence interval; OR, odds ratio; TDI, traumatic dental injury.
Variables incorporated into the multivariate model (P < 0.20): mother’s schooling; monthly household income; perception of oral health; toothache; dental caries; caries severity; and type of TDI.
DISCUSSION
In the present investigation, mother’s schooling, and toothache and tooth avulsion or luxation in preschool children, exerted an impact on family functioning, causing parents or guardians to miss days of work. This study contributes to the literature by demonstrating such an association in a representative, preschool-based sample. Previous studies have addressed the frequency of work absenteeism caused by dental problems in preschool children, reporting rates ranging from 3.4% to 12.5%5., 18., 19.. However, none of the studies cited described determinant factors of work absenteeism. Although the prevalences of oral conditions were high among the children, only 9% of the parents had work absenteeism. This could be because one of the parents or guardians was unemployed.
Caring for the health of a child requires considerable resources, including time and money32. Quantifying lost time and potential losses in productivity as a result of health problems allows a broader discussion beyond mere clinical aspects of adverse health conditions9. Thus, the analysis of factors associated with missed days of work furnishes useful population statistics for measuring the social impact of oral health33.
A low level of mother’s schooling was a predictor of parents’ or guardians’ work absenteeism because of the oral conditions of their preschool children, which may be associated with less knowledge regarding healthy choices that help maintain satisfactory oral health34., 35.. A low degree of mother’s schooling leads to less interest in preventive treatment36 and may act as an indirect factor for the absenteeism of parents because of the need to seek curative dental treatment for their children. Moreover, most preschool children in Brazil make use of public dental services37, which are generally offered during business hours, leading to a greater amount of work absenteeism in social classes that cannot afford private dental care.
A child’s history of toothache was significantly associated with work absenteeism, which demonstrates that family functioning is affected by pain symptoms, regardless of the causal factor. Indeed, toothache is one of the main reasons for seeking dental treatment in this age group38 and requires a parent or guardian to accompany the child. A study conducted in Canada, involving individuals 6–70 years of age, found that toothache was associated with an average loss of 4 hours of time9 Thus, although dental caries was highly prevalent, it does not seem to affect family functioning in the early stages39. Moreover, the severity of caries was not associated with work absenteeism, perhaps because of a possible interaction with toothache, as severe caries that do not cause pain may go unnoticed by parents or guardians.
TDI occurs unexpectedly and requires immediate treatment40. In the present study, tooth avulsion or luxation was associated with work absenteeism, probably because of its classification as ‘complicated TDI’. Treating TDI is a complex issue in the management of child and adolescent health care. Besides the emotional stress, children can experience pain and discomfort, and parents or guardians are forced to put off their work commitments to take the child for treatment4., 5., 41..
The present study has limitations that should be addressed. Information bias may have occurred in relation to household income, and memory bias may have occurred regarding aspects related to the past, such as a history of toothache and the B-ECOHIS questionnaire used to analyse work absenteeism. Moreover, because of the lack of temporal relationship in this type of study, the prevalence of TDI was probably underestimated, as past occurrences of TDI may not have been diagnosed in subsequent clinical examinations. However, measures were taken to minimise the occurrence of such sources of bias, such as the use of a validated questionnaire and the execution of a pilot study. Moreover, the present study involved a sample of adequate size and multivariate analysis was performed; thus, the results are reliable.
The reduction in social impact caused by oral conditions requires investments in programmes and services that correspond to the needs of the target population. It is important for governments to consider offering care to the population with flexible hours and to establish effective prevention programmes in preschools. If such measures were taken, the frequency of work absenteeism among parents or guardians would tend to diminish, considering the association between work absenteeism and the need to seek curative treatment for children. Longitudinal studies are needed to evaluate the impact of oral conditions in children on the work activities of parents or guardians over time.
Acknowledgements
This study was supported by the State University of Paraíba (UEPB), the Brazilian Coordination of Higher Education, Ministry of Education (CAPES), the Research Foundation of the State of Minas Gerais (FAPEMIG) and the National Council for Scientific and Technological Development (CNPQ), Brazil.
Conflict of interest
The authors declare that they have no competing interests.
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