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 Table of Contents  
ORIGINAL ARTICLE
Year : 2021  |  Volume : 19  |  Issue : 2  |  Page : 144-151

Concordance between Libyan Child and Parent Self-Reports of Oral-Health-Related Quality of Life


1 Department of Community and Preventive Dentistry, Faculty of Dentistry, University of Benghazi, Benghazi, Libya
2 Sir John Walsh Research Institute, University of Otago, Dunedin, New Zealand
3 Department of Oral Biology, Faculty of Dentistry, University of Benghazi, Benghazi, Libya
4 Department of Paedodontic, Faculty of Dentistry, University of Benghazi, Benghazi, Libya

Date of Submission27-Sep-2020
Date of Decision30-Apr-2021
Date of Acceptance20-Jun-2021
Date of Web Publication2-Aug-2021

Correspondence Address:
Eman K M Mansur
Department of Community and Preventive, Faculty of Dentistry, University of Benghazi, Benghazi
Libya
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jiaphd.jiaphd_186_20

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  Abstract 


Background: Measuring oral health-related quality of life (OHRQoL) is a person-centered approach to investigating oral health. Proxy reports by parents or caregivers were used for assessing children's health-related quality of life (HRQoL) for decades. Using appropriate questionnaire techniques, it has become possible to get valid and reliable information from children about 8 years of age. Aims: The aim of the study was to investigate the OHRQoL of 8–10-year-old Libyan schoolchildren from viewpoints of both the children and their parents, in order to evaluate the concordance between child and parent ratings. Materials and Methods: This is a cross-sectional study using a representative sample of 303 8–10-year-old Libyan schoolchildren. Data were collected using Arabic versions of the Child Perception Questionnaire for 8–10-year-old children (CPQ8–10) and the Parent-caregiver Perception Questionnaire (P-CPQ8). Participants were examined for both traumatic dental injuries (TDI) and dental caries. Questions about the mother's and father's educational levels and current occupations were also asked, along with information on the child's age and sex. The collected data were analyzed using SPSS for Windows, version 25.0 (SPSS Inc., Chicago, USA). The alpha value was 0.05. Results: The mean CPQ8–10 score was 3.5 ± 4.2 (range: 0–18) overall, and those who had had caries experience or a TDI had higher CPQ8–10 scores, on average. The mean P-CPQ8 score was 7.5 ± 5.4 (range 0–27), and there were no apparent differences by parental education or employment status. The association between child and parental ratings of the children's OHRQoL was weak. The parents overestimated OHRQoL relative to their children's self-assessments. Conclusions: There is relatively low agreement between Libyan children and parents in their responses to OHRQoL scales, particularly in cases where that impact is greater. Where possible, if the aim is to obtain a more complete picture of the impact of a child's oral state on his/her life, both child and parental reports should be used.

Keywords: Child perception questionnaire, dental caries, Libya, oral health-related quality of life, oral health, parental-caregiver perceptions questionnaire, quality of life, traumatic dental injuries


How to cite this article:
Mansur EK, Thomson WM, Buzaribah KS, Elsheibani SB. Concordance between Libyan Child and Parent Self-Reports of Oral-Health-Related Quality of Life. J Indian Assoc Public Health Dent 2021;19:144-51

How to cite this URL:
Mansur EK, Thomson WM, Buzaribah KS, Elsheibani SB. Concordance between Libyan Child and Parent Self-Reports of Oral-Health-Related Quality of Life. J Indian Assoc Public Health Dent [serial online] 2021 [cited 2021 Nov 28];19:144-51. Available from: https://www.jiaphd.org/text.asp?2021/19/2/144/322859




  Introduction Top


Measuring oral health-related quality of life (OHRQoL) is a person-centered approach to investigating oral health.[1] For decades, proxy reports by parents or caregivers were used for assessing children's health-related quality of life.[2] Using appropriate questionnaire techniques, it has become possible to get valid and reliable information from children about 8 years of age.[3] The Child Perceptions Questionnaire (CPQ) originally published by Jokovic et al. in 2002 is one of the most commonly used self report measures for use with children.[4] As part of the same suite of measures, the Parental-Caregiver Perceptions Questionnaire (P-CPQ) was published by Jokovic et al. in 2003; it was intended to obtain parental proxy reports to complement children's self-ratings or to substitute for those where the child was too young to use a self-report questionnaire.[5]

Evaluations of parent–child agreement on ratings of children's OHRQoL have been inconclusive, with the connection not completely understood.[6] A systematic review of parent–child agreement in rating OHRQoL showed that they may have different views, and some of parents are with limited knowledge of their children's OHRQoL, especially the impact on social and emotional well-being (EWB).[7] Some studies found that the concordance between parents and children reports of OHRQoL is low.[6],[8] However, other studies reported the concordance to be moderate or even good.[9],[10] The majority of the studies in this field concluded that children overestimated the impact of oral conditions on their OHRQoL.[8],[9],[10] The parents' overestimation of the impact of oral conditions on their children's OHRQoL was also reported.[2],[11]

Libya is a country in North Africa; its population is 6,293,000 in 2016. Dental caries experience in Libyan children is high, with much of it untreated.[12] In recent decades, it has been the main cause of tooth loss.[13] Moreover, a considerable proportion of Libyan children have traumatic dental injuries (TDIs) and with relatively high unmet treatment needs.[14] TDIs have been an important contributor to tooth loss.[13] These conditions impair children's day-to-day lives, but there have been relatively few scientific reports from North Africa about the impact of poor oral health on children's quality of life and even fewer from Libya.[15],[16] Only one previous study has reported on OHRQoL among Libyan children and that investigated the impact of malocclusion on it.[17] Information on Libyan children's OHRQoL is important for identifying and dealing with their oral health needs. Accordingly, this study investigated the OHRQoL of 8–10-year-old Libyan schoolchildren from the viewpoints of both the children and their parents using Arabic versions of the CPQ8–10 and the P-CPQ8[18],[19] in order to evaluate the concordance between child and parent ratings.


  Materials and Methods Top


Approved by the Ethics Committee of Faculty of Dentistry, Benghazi University (ref: 3-1/183/2019), this was a cross-sectional study using a representative sample. It was conducted in March and April 2019 in Benghazi, the second-most populous city in Libya, with an estimated population of 631,555 (in 2011). The participants were selected from a population of 32,123 8–10-year-old schoolchildren who were enrolled at 102 public primary schools in Benghazi from September 2018 to June 2019 (Libyan Ministry of Education). Only children with no systemic and/or mental developmental disorders were participated in this study.

The sample size was calculated at 5.5% margin of error, a 95% confidence interval, and an assumed concordance of 50%. The minimal sample size to satisfy those parameters was estimated at 314 participants. The sample was increased by 40% to compensate for anticipated lower participation, giving a required total of 440 schoolchildren.

Benghazi is divided into four educational offices: Centre of Benghazi (20 schools with 5439 children aged 8–10 years old); Alsalawi (15 schools with 5773 children aged 8–10 years old); Sedi Khalifa (7 schools with 2387 children aged 8–10 years old); and Alberka (60 schools with 18,524 children aged 8–10 years old). Nearly 17% of the sample was from three schools from the Centre of Benghazi, 18% from three schools in Alsalawi, 7% from one school in Sedi Khalifa, and 58% from 9 schools in Alberka. In the first stage, schools were randomly chosen in each educational office of the city. In the second stage, classes with the target age groups were chosen randomly. In the third stage, equal number of boys and girls in each class were selected randomly by simple random method. After sample selection (440 schoolchildren), the parent of each selected child received an invitation letter, a parental consent form, and a questionnaire. After parental consent was obtained, participants completed the questionnaires before children were examined in their schools, and only those whose parents completed and returned the questionnaire were included in the current study.

Data were collected from parents using the Arabic short-form version of the P-CPQ8. A questionnaire was excluded from the current analysis if there were one or more missing responses. Children were asked to complete the Arabic version of the CPQ8–10 on the day of the dental examination. After questionnaire distribution, the children received a short explanation and instructions on how to complete it. All parents and all children understood Arabic.

The Arabic short form version of the P-CPQ8 includes eight items, organized into four subscales: oral symptoms (OS), functional limitation (FL), EWB, and social well-being (SWB). The original Arabic version of the CPQ8–10 includes 25 items, distributed among the same four subscales. Both of the scales addressing the frequency of events in the previous 3 months and use the following five ordinal response options: Never = 0; once or twice = 1; sometimes = 2; Often = 3; and every day or almost every day = 4. “Don't know” responses were recorded as 9. Since there was no short-form version of the CPQ8−10, we created one using the same eight items which are included in the P-CPQ8. The correlation between the short-form score and the original 25-item scale score was 0.93 (Pearson correlation coefficient), suggesting little attenuation of the scale properties. Both questionnaires have eight items, with two items on each subscale. The overall score is computed by adding up the scores for all questions, and scores for each of the four subscales can also be computed separately. The overall score on both questionnaires ranges from 0 to 32. A higher total score on the scale points to a greater impact of the oral condition on a child's quality of life.

The clinical examinations were conducted by three experienced dentists, who had been calibrated before the examinations started. The inter-and intra-examiner tests (using repeat examinations on 20 children) showed kappa statistics ranging from 0.82 to 1.00. The clinical dental examination was conducted during daytime hours in a private room at each school. In order to reduce the risk of cross-infection, a disposable diagnostic kit was used for each child, and the examiner used disposable masks and gloves. Participants were examined for both TDIs and dental caries, using the World Health Organization methods.[20] For the current analysis, children were categorized as having “no TDI” if there was no sign of injury, or “TDI” if there was any sign of injury. Similarly, their dental caries experience was scored as “caries” if they had one or more decayed, missing of filled deciduous or permanent teeth, or “no caries” if they did not.

Questions about the mother's and father's educational levels and current employment were developed from the literature. For assessing the highest level of education received, the following response options were used: primary, secondary, and tertiary. The current employment was assessed using the response options of employed and unemployed. These questions were asked along with information on the child's age and sex.

The collected data were analyzed using SPSS for Windows, version 25.0 (SPSS Inc., Chicago, USA). Scale scores were computed, after which their internal consistency was assessed using Cronbach's alpha. “Don't know” responses were considered as missing data, and the current study used complete case analysis. After the generation of descriptive statistics, cross-tabulations and Chi-square tests were used to examine differences with categorical variables. Nonparametric tests (Mann–Whitney U or Kruskal–Wallis tests, as appropriate) were used to test the statistical significance of observed differences in scale scores. The alpha value was 0.05.

The concordance between child and parental ratings was assessed using scatterplots and Pearson's correlation coefficient, along with a difference against mean plot (Bland–Altman plot). The level of agreement presented by the Pearson's correlation coefficient was categorized as follows: 0.90–1.00 “very high;” 0.70–0.90 “high;” 0.50–0.70 “moderate;” 0.30–0.50 “low;” and 0.00–0.30 “very low.” The Bland–Altman plot was prepared as follows: after the short-form CPQ8–10 score was computed by summing the eight items, it was standardized by dividing by the number of items. The P-CPQ8 score was then computed and standardized by dividing by the number of items. The difference between the standardized P-CPQ8 and CPQ8–10 was then calculated, along with the mean of the standardized P-CPQ8 and CPQ8–10, and a scatterplot of the two was produced.


  Results Top


Of the 440 questionnaires which were sent to the parents, 37 were not returned and 29 were excluded; 24 of them due to incomplete information, and 5 due to the children being absent from school on the days scheduled for the clinical examinations. Hence, the examined sample comprised 374 (85.0%) participants. Some seventy of the parent questionnaires and one child questionnaire had one or more missing scale responses, and so those were omitted from the current analysis, leaving a final sample of 303 participants (68.9%) for the current study. There were no systematic differences between the 71 with missing data and the other 303.

[Table 1] summarizes the characteristics of the sample. There were slightly more males than females, and there was an approximately even distribution of the sample across the ages 8, 9, and 10 years. Just over one-half of mothers, but only one in three fathers, had been educated to tertiary level, and two-thirds of fathers were employed. Most children had dental caries experience. A higher proportion of the older children had evidence of past dental trauma, but there were no other clear differences in caries prevalence or dental trauma by sociodemographic characteristics.
Table 1: Characteristics of the study sample (brackets contain row percentage unless otherwise indicated)

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Cronbach's alpha scores for the CPQ8–10 scale and the P-CPQ8–10 were 0.71 and 0.74, respectively. The mean CPQ8–10 score was 3.5 ± 4.2 (range 0–18) overall. [Table 2] presents mean CPQ8–10 scale and subscale scores by sex, age, and dental caries experience, whether the child had evidence of a TDI, and parent characteristics. Those who had had caries experience had higher mean CPQ8–10 scores overall and higher mean scores on the FLs and EWB subscales. As well, those with a TDI had higher mean scores overall, with higher mean scores on the emotional and SWB subscales.
Table 2: Mean Child Perception Questionnaire 8-10-year-old children scale and subscale scores by child and parent characteristics

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The mean P-CPQ8 score was 7.5 ± 5.4 (range 0–27). [Table 3] presents summary data on P-CPQ-8 scores by sex, age, dental caries experience, whether the child had evidence of a TDI, and parent characteristics. Those with a TDI had a lower mean score on the EWB subscale. Mean SWB subscale scores were higher for children whose mothers had less education or who were unemployed.
Table 3: Mean Parent-reported Child Perceptions Questionnaire 8–10-year-old children scale and subscale scores by child and parent characteristics

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Plots of the standardized CPQ8–10 and P-CPQ8 scores are presented in [Figure 1] [and in [Appendix Figure 1]] for each of the four subscales]. The difference against mean plots show that the parents tended to overestimate the impact on the child (relative to the child's assessment) and that the extent of that overestimation was greater where there were more child-reported impacts [Figure 1]a. This was apparent with the overall scale scores and with the EWB scores in particular. The Pearson correlation coefficient between the child and parental ratings of the children's OHRQoL was 0.24, indicating a weak positive correlation.
Figure 1: Difference against mean plots and simple scatterplots for the standardized parent-caregiver Perception Questionnaire 8 and Child Perception Questionnaire for 8–10-year-old children. (a) “Difference against mean” plot for the standardized Parent-caregiver Perception Questionnaire 8 and Child Perception Questionnaire for 8–10-year-old children scale scores (bias is toward over-estimation by the parent, and for that bias to be greater with higher scale scores). (b) Simple scatterplot of standardized Parent-caregiver Perception Questionnaire 8 and Child Perception Questionnaire for 8–10-year-old children scale scores

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  Discussion Top


This study evaluated the OHRQoL of a representative sample of a 8–10-year-old Libyan schoolchildren from the viewpoints of both children and their parents. The Arabic version of CPQ8–10 and the Arabic short form version of P-CPQ8 were used along with clinical examinations. Statistically significant differences in the children's OHRQoL were found only in relation to dental caries and TDI. The concordance between child and parental ratings was low, and parents tended to overestimate the impact on their children, particularly in relation to EWB.

The correlation between child and parental ratings of the children's OHRQoL was low. This finding is in accordance with those from studies in Hong Kong by Zhang et al. in 2007 and in Sweden by Dimberg et al. in 2019.[6],[8] This can be explained by the notion that parents' knowledge of their children is expected to be restricted, particularly in regard to internal feelings and activities and relationships outside the family setting. In addition, the extent to which parents understand the effects of health and illness on their children's lives remains unanswered.[8] However, the findings are at variance with those from the Canadian study by Jokovic et al. which found that, at the group level, agreement between mothers and children was good.[9] They also differ from those of a Brazilian study, which observed moderate agreement between child and maternal reports of OHRQoL.[10]

On average, in the current study, the parents had higher scale scores than the children did. This was apparent with the overall scale scores and with the EWB scores in particular, meaning that they overestimated the impact of oral conditions on their children's OHRQoL. The reasons for this are unclear, but it is likely that parents and children differed in their interpretation of the ordinal response options (what is “often” to the child might be quite different for the parent, for example), but we have no way of investigating this using the current study's design. This overestimation might lead to the expressed needs (”demand”) exceeding felt needs (”want”) in this population, leading to the possibility of misallocated oral care resources. This finding is consistent with some earlier studies.[2],[11] But not with many others.[5],[8],[9],[10]

Moreover, whether the standardized scale score was high or low affected the extent of the agreement; parent–child pairs with score below the median of 0.7 had twice the possibility of agreement than those with scores above the median. This means that the agreement between parent and child was greater with better OHRQoL. This is reasonable since, if the child has no (or few) problems, it will be easier for the parent to rate in agreement with him/her.[8]

In the current study, there was no difference in the children's reporting of their OHRQoL with respect to age and gender. This result confirms the findings of a systematic review of factors influencing OHRQoL in children in Africa.[21] And disagree with Barbosa and Gaviao in 2008.[7] However, in the current study, there were differences in the OHRQoL between children in relating to their dental caries and TDI experiences. These findings match those reported in earlier studies.[22],[23],[24] Moreover, they disagree with other studies.[21],[25] On average, with respect to parents' occupation status and educational level, there was no difference in their ratings, which is at variance with the majority of the studies.[21],[25]

The Arabic versions of the scales had been validated outside Libya, and we were unable to undertake further validation before data collection; this means that at least some of the observed nonconcordance may be due to the instruments themselves being not as valid as they should have been. Furthermore, the parents' questionnaire was sent to them at home, and that made it difficult for us to determine whether the mother or the father completed it. Accordingly, we considered “Don't know” responses to be missing data, with the reasoning that responses should come from somebody who takes care of the child, otherwise they may not be valid; another consequence might be recurrent “don't know” responses. Considering the study's strengths, the data are from a stratified random sample, which makes the findings generalizable to the wider population. In addition, the sample consisted of a single ethnic group (Libyans).

Even though parents' reports may be incomplete, because of their lacking knowledge of some child experiences, they still deliver useful information.[26] Their reports can supplement children's reports on OHRQoL impacts, and if one report is favored over the other, important information may be lost.[10] Moreover, parents make important health decisions on their children's behalf, with child health care providing for the child's needs as well, meaning that parents' ratings of their children's health make useful information for health services research and evaluation. Where possible, if the aim is to obtain a more complete picture of the impact of a child's oral state on his/her life, both child and parental reports should be used.


  Conclusions Top


There is relatively low agreement between Libyan children and parents in their responses to OHRQoL scales, particularly in cases where that impact is greater. Where possible, if the aim is to obtain a more complete picture of the impact of a child's oral state on his/her life, both child and parental reports should be used.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

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