|Year : 2014 | Volume
| Issue : 5 | Page : 559-566
|Development and validation of oral health-related early childhood quality of life tool for North Indian preschool children
Vijay Prakash Mathur1, Jatinder Kaur Dhillon2, Ajay Logani3, Ramesh Agarwal4
1 Division of Pedodontics and Preventive Dentistry, Centre for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, India
2 Department of Pedodontics and Preventive Dentistry, Maulana Azad Institute of Dental Sciences, New Delhi, India
3 Division of Conservative Dentistry, Centre for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, India
4 Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
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|Date of Submission||28-Apr-2014|
|Date of Decision||20-Jul-2014|
|Date of Acceptance||30-Oct-2014|
|Date of Web Publication||16-Dec-2014|
| Abstract|| |
Objective: The purpose of this study was to develop a reliable instrument [Oral Health related Early Childhood Quality of Life (OH- ECQOL) scale] for measuring oral health related quality of life (OHrQoL) in preschool children in North Indian population.
Methodology: Four pediatric dentists evaluated a pool of 65 items from various QoL questionnaires to assess their relevance to Indian population. These items were discussed with eight independent pediatric dentists and two community dentists who were not a part of this study to assess relevance of these items to preschool age children based on their comprehensiveness and clarity. Based on their responses and feedback a modified pool of items was developed and administered to a convenience sample of 20 parents who rated these items according to their relevance. The test retest reliability was evaluated on another sample of 20 parents of 2-5 year old children. The final questionnaire comprised of 16 items (12 child and 4 family). This was administered to 300 parents of 24-71 months old children divided on the basis of early childhood caries to assess its reliability and validity.
Results: OH-ECQOL scores were significantly associated with parental ratings of their child's general and oral health, and the presence of dental disease in the child. Cronbach's alpha was 0.862, and the ICC for test-retest reliability was 0.94.
Conclusions: The OH-ECQOL proved reliable and valid tool for assessing the impact of oral disorders on the quality of life of preschool children in Northern India.
Keywords: Early childhood caries, health perceptions, psychosocial aspects of oral health, quality of life
|How to cite this article:|
Mathur VP, Dhillon JK, Logani A, Agarwal R. Development and validation of oral health-related early childhood quality of life tool for North Indian preschool children. Indian J Dent Res 2014;25:559-66
Traditional methods of assessment of oral health did not take into account the impact of oral health status on the lives of people. This led to the concept of oral health-related quality of life (OHRQoL), which was first given by Giddon in 1978.  It is defined as/an individual's assessment of how the following affect his or her well-being: Functional factors, psychological factors, social factors, and experience of pain/discomfort in relation to orofacial concerns.  In simple words, OHRQoL is the effect of oral health on a person's functioning (eating, speaking), sensation of pain, psychological well-being (appearance and self-esteem) and social well-being. The concept of OHRQoL emphasizes that the improvement of a person's quality of life (QOL) should be the outcome of any intervention or treatment.  This promotes a more holistic approach toward treating people and widens the perspective and hence that the clinician treats the patient as a whole not just body parts.
|How to cite this URL:|
Mathur VP, Dhillon JK, Logani A, Agarwal R. Development and validation of oral health-related early childhood quality of life tool for North Indian preschool children. Indian J Dent Res [serial online] 2014 [cited 2019 Nov 13];25:559-66. Available from: http://www.ijdr.in/text.asp?2014/25/5/559/147078
A number of OHRQoL measures have been developed and used for assessing oral well-being to describe oral impacts on people's QOL. The OHRQoL instruments designed to assess the impact of oral conditions on the daily living of children and adolescents are the child-oral impacts on daily performances,  the early childhood oral health impact scale (ECOHIS),  the child perceptions questionnaire (CPQ),  the Michigan OHRQoL scale,  the child oral health impact profile  and scale of oral health outcomes for 5-year-old children (SOHO-5).  Among these ECOHIS,  Michigan OHRQoL scale  and SOHO-5  are the only instruments available to assess the OHRQoL of preschool children. Among these two scales, ECOHIS has been translated into various languages including Portuguese,  Chinese,  Farsi  and French.  However, neither of these scales has been used in the Indian population which has different cultural contexts. Since the concept of OHRQoL comprises social well-being also, it is important that the social environment of a population should also be considered while assessing the same. This is especially true of Indian population where cultural beliefs often supersede logic. India is a country where both extremes of economic status and literacy levels often co-exist. This necessitates that modifications are to be made in any tool that assesses the subjective aspect of a person's QOL according to the literacy levels and demography. The scales for measurement of OHRQoL developed elsewhere could not be utilized only by linguistic translation due to the reasons cited. Moreover, there is a difference in the attitudes of Indian parents towards oral health in comparison with other parts of the world as oral health of children is given low priority in general. Therefore, the present study has been conceptualized to develop and validate a measure for OHRQoL for Indian preschool children that are, oral health related early childhood quality of life (OH-ECQOL). It is expected that the tool thus developed would help in Indian researchers and policy makers in understanding impact of child's oral health on QOL and also help in appropriate planning and management of health programs.
| Methodology|| |
Keeping the above background in mind, it was decided to develop a new reliable and valid tool to assess the OHRQoL of Indian preschool children. The new qualitative tool being developed was named as OH-ECQOL scale. The population residing in the northern part of the country has relatively same native language (Hindi) and therefore the present scale would be considered for north Indian population. It is expected that this scale can easily be translated in other Indian language (with appropriate translation validation) and used in other parts of the country. The ethical clearance for conduct of the study was obtained from the institutional ethics committee of All India Institute of Medical Sciences, New Delhi and the tool development, and validation was done in the following manner:
Development and validation of the oral health-related early childhood quality of life scale for Indian population
This comprised of two stages.
This involved two steps: Item generation and item reduction:
A pool of 46 impact items given by Jokovic et al. (2003)  and items obtained from child health questionnaire,  infant and Toddler quality of life questionnaire (ITQOL) , and Early ECOHIS  were used for the initial item pool representing descriptive domains of symptom, function, emotional and family/social well-being. Another domain that comprised of systemic well-being was added to the above four domains after discussion between the investigators. This domain addressed systemic complaints which might arise with oral problems such as fever, sore throat, earache, weight loss, etc.
A group of four pediatric dentists was selected as these professionals regularly come in contact with children in the selected age group suffering from early childhood caries (ECC). This group then discussed these items and eliminated the items found to be less relevant. Few items were added as per their experience that led to a total of 82 items. These items were then sent via e-mail to eight independent pediatric dentists and two community dentists who were not a part of this study and willing to participate in the study, to assess relevance of these items to preschool age children on a scale of 0-2; 0 - irrelevant, 1 - maybe relevant and 2 - definitely relevant. A three-point scale was used as the investigators observed that using a five-point scale created confusion when translated in the vernacular language. They were asked to select items based on their comprehensiveness, relevance and clarity and exclude those items that they found to be irrelevant according to their clinical experience with children and parents. Their responses were entered in MS Excel 2007 sheet (Microsoft) and based on the total score obtained and their feedback a modified pool of items was developed. The modified pool of items was then administered to a convenience sample of 20 parents having one or more children in the age group of 24 months to 71 months, reporting to the OPD in Department of Pedodontics and Preventive Dentistry after obtaining their informed consent. The parents were asked to suggest whether any other item should be included and to comment upon the relevance of each item on a scale of 0-2; 0 - irrelevant, 1 - maybe relevant and 2 - highly relevant.
Validation and testing
The proforma was tested on 300 parents with children between 24 and 71 months of age reporting to the OPD of Pedodontics and Preventive Dentistry in a Tertiary Care Hospital. Informed consent was obtained from the parents for participation in the study. Initially, it was decided to use a five point Likert scale with the options as (never, hardly ever, occasionally, often, and very often). However, it was observed that a major cause for concern amongst the parents was the number of options which many participants found confusing and difficult to answer as in the vernacular translation the responses were close to each other in meaning. It was, therefore, decided to convert the scale to a simple 3-point Likert scale. Responses to each item were scored on a three-point scale to assess the frequency of an event occurring: (1) Never, (2) occasionally, (3) often. Two more questions were included asking the parent/caregiver about the global rating of their child's general and oral health. These global ratings had a five point response format: 1 = Excellent, 2 = Very Good, 3 = Good, 4 = Fair and 5 = Poor.
The oral health status was assessed using WHO oral health assessment form (2004).
The analysis was performed using SPSS (IBM Corporation) to find out whether the research tools thus developed were able to answer the research question and fulfill the objectives of the study. This was assessed by:
Concurrent or criterion - related validity
This was carried out by comparison of OH-ECQOL scores with the answers to self- rating questions on global and oral health. It was assumed that higher the level of satisfaction with dental appearance, better will be the perceived oral and general health.
Convergent or construct - related validity
This was tested by correlating scores in the child impact section with the family impact section. The hypothesis related to this test is that the impacts of the child's oral health status on his/her life are closely related to its impacts on the family.
This was done by comparing the OH-ECQOL scores in children with and without ECC. The hypothesis is that OH-ECQOL would be higher among children affected with caries as compared to caries-free children. The children were divided into three groups based on classification of ECC given in AAPD guidelines:  Group 1 was assigned to children without ECC, group 2 was assigned to children with mild to moderate ECC and group 3 was assigned to children with severe ECC.
Internal consistency reliability
It was tested by assessing the mean item correlation of items within OH-ECQOL using Cronbach's alpha coefficient which captures the extent of agreement between all possible subsets of items.
Among these 300 parents, a random sample of 20 parents were recalled after 2 weeks and reported no change in the oral health status of their child from a previous visit and the questionnaire was administered to them again. This was done on a sample of 20 parents. Test - retest reliability was assessed by determining the level of agreement between initial assessments of OH-ECQOL and the scores obtained at the second assessment using intra-class coefficient (ICC). The steps in the methodology are summarized in [Figure 1].
|Figure 1: Steps in the development of oral health related early childhood quality of life|
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| Results|| |
Item reduction and pre testing
Total scores, mean scores and standard deviations were calculated for each item. The total score for each item was then subtracted from the corresponding mean, and divided by its standard deviation to obtain standardized scores. The items were then ranked in decreasing order of "importance" based on these standardized scores. Based on the feedback by the independent assessors few items were combined to form a single question. e.g. difficulty eating firm/fibrous food and difficulty eating/drinking hot/cold food/drinks were combined to form a single question. This proforma was administered to 20 parents as described above. The parental responses were also entered in MS Excel 2007 and the items scoring the highest standardized scores were included in the final questionnaire. The final proforma thus comprised of 16 questions with a minimum score of one and a maximum score of three for each question. Thus, the minimum score possible for the proforma was 16 and the maximum score possible was 48. Two more questions were included in the questionnaire obtained above asking the parent/caregiver about the global rating of their child's general and oral health.
| Validation and testing|| |
The results obtained after administering the pre tested questionnaire are described below:
[Table 1] represents the distribution of responses to the OH-ECQOL among the sample of parents. The items related to pain, food caught between teeth, difficulty eating, bad breath and mouth breathing was reported most frequently on the child impacts section. Item related to being worried was reported frequently on the family impacts section of the OH-ECQOL. Parents reported more child impacts (94.67%) than family impacts (80%); about 16 and 60 parents reported floor effect (the lowest possible score of 12 and 4) on the child and family sections, respectively. No ceiling effect was observed for child impacts section (i.e. scores of 36 on child impacts section) whereas ceiling effects were observed for six parents in family impacts section (i.e. scores 12 on the family impact sections).
Demographic characteristics of the population
The participants of this study were from a convenience sample. The caries and caries-free groups were not sex, and age matched. The socioeconomic status of parents was scored based on Kuppuswamy index  for socioeconomic status. The demographic characteristics of the parents and children included in the study are given in [Table 2].
|Table 2: Demographic characteristics of parents and children included in the study for validation |
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Concurrent or criterion - related validity
The Spearman correlation coefficient between the child impact section versus perception of oral and general health and family impact section versus perception of oral and general health was as depicted in [Table 3]. The Spearman correlation coefficient between total OH-ECQOL scores and the perception of parents regarding their child's general and oral health was observed to be 0.388 and 0.478 respectively (significant at 0.01 level).
Convergent or construct - related validity
This was calculated using Spearman's correlation and was found to be 0.621 which was significant at 0.01 level [Table 4].
One-way ANOVA was used for comparison between the groups and post hoc Bonferroni comparison was applied. The results are depicted in [Table 5] and [Table 6].
|Table 6: Inter group comparison using post-hoc Bonferroni comparisons indicating discriminant validity |
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Internal consistency reliability
The Cronbach's alpha was calculated to be 0.862 and the Cronbach's Alpha based on standardized items was 0.870. The item scale correlation ranged from 0.484 to 0.659 where the lowest score of 0.484 was for the systemic well-being domain and the highest score of 0.659 was for a domain of functional limitations.
The ICC was 0.9414 showing excellent intra-observer or test-retest reliability.
| Discussion|| |
Various tools have been developed to assess the QOL for older children and adults. However, there are few for children below 6 years of age. Moreover, the tools available might not be valid considering the social, economic and cultural differences in Indian population as compared to other countries. Another aspect to consider while developing such a tool for young children is the level of maturity and social, cognitive and emotional development along with linguistic ability of the children which makes it difficult for them to answer the questions posed to them. This is one of the reasons SOHO-5 was not considered as it is a self-reported scale and very young children such as 2-3 year olds are unable to express themselves. It is also seen that adults (usually parents in India) are responsible for making decisions about the child's health. Thus, it is important that the parents' perceptions about the effect of oral health on the QOL of their child are assessed. This will enable us to educate the parents and promote good oral health. ECC results in parents/caregivers missing work and expenditure in terms of money as well as time.  Thus, it is also important to measure the effect of such factors while assessing OHRQoL of young children. With this background, it was decided to develop a valid and reliable tool that is, OH-ECQOL; to assess the impact of oral health problems on QOL of preschool children in North India.
Oral health-early childhood quality of life proforma thus developed consists of a total of 16 items with 12 items in child impact and four items in family impacts section. The procedure followed for developing the tool was as described by Guyatt et al.,  Juniper and Guyatt  and Juniper and Guyatt.  These items comprised of the descriptive domains of symptom, function, emotional and social well-being in the child impacts section and family well-being as given by Jokovic et al. 
The initial pool of items was developed using various pre-existing QOL questionnaires given by Jokovic et al.,  Pahel et al.,  Landgraf et al.  making a total number of 65 items. Few items were modified or added by four pediatric dentists including investigators 1, 2 and 3 and a pediatrician (investigator 4) taking the total to 82 items. A question on systemic health was included that "whether the child had a fever due to oral problems?" It is a common complaint reported by parents in India due to untreated dental caries and subsequent abscess, malaise, etc., Therefore, a fifth domain of systemic well-being was also added to the questionnaire. With the inputs of other dental professionals and a convenience sample of 20 parents as described above in the methodology, the items were rated according to their scores. Standardized scores were used for each item as these allowed us to calculate the probability of a score occurring within the item's normal distribution and enabled comparison between different items. Moreover, we used a three point scale regarding relevance of each item as it allowed easy understanding and scoring. Another reason for selection of three point scale was that the questionnaire had to be converted into the local language. If a five point scale had been used, its vernacular translation would have created confusion amongst parents as all the options would have been close to each other in meaning. This led to a total of 16 items being included in the final OH-ECQOL. Two questions were added regarding perception of parents about the general health and oral health of their child to enable validity testing. The global measures are subjective indicators which are commonly used and are highly correlated with clinical indicators of oral health. The oral status was also recorded in terms of severity of ECC by counting number of carious teeth and to enable classification of the subjects into different disease groups and to enable testing discriminant validity. The classification of subjects was done based on AAPD definition of ECC. This was used as it enabled grouping of subjects with different age groups and different oral health status in an objective manner.
Final validation of OH-ECQOL questionnaire was done using the criterion described above. The responses were recorded on a three point scale due to linguistic reasons and to keep it simple for the participants, a simple 3-point Likert scale was used as cited by Atchison ,,,, where the English equivalent of "very often" and "often" was clubbed together as "often"; "hardly ever" and "never" was clubbed into "never"; thereby giving often, occasionally and never as the three options.
The reason for developing a tool for the below 6 years of age was that the investigators often encounter this age group in their clinical routine and wished to have a reliable tool for predicting the OHRQoL of these children so as to enable them to educate the parents as well as general public regarding the effects of oral problems on QOL of children. The lower limit of inclusion in the study was kept as 24 months or 2 years as it is difficult to assess the effect of dental problems in these children due to limited speech and vocabulary. Such young children might not be able to convey their problems to their parents. Also, as the deciduous dentition is still often developing the problems may be ignored due to lack of awareness.
Concurrent or criterion - related validity
Concurrent validity was tested on several levels. The scores in general health and oral health global ratings were correlated with child impacts (0.363 and 0.431 respectively) as well as family impacts (0.342 and 0.455 respectively). The total OH-ECQOL scores with general health and oral health global ratings correlation was also found to be significant (0.388 and 0.478 respectively). Parents of children with higher OH-ECQOL scores perceived their child's general health as well as oral health to be poorer than in children with lower scores. The global ratings were used for this purpose as these have been demonstrated to be correlated to the actual disease status. This proved that OH-ECQOL was valid in terms of criterion related validity. This is also in agreement with the study by Pahel et al.,  Scarpelli et al.  and Jabarifar et al. 
Construct related validity
In order to study the construct validity, scores of various sections were compared. The results showed a significant correlation between the items in child impacts section and family impacts section. This is important as often the impacts on the family in terms of financial loss or emotional distress are as important as discomfort for the child in seeking treatment and taking appropriate preventive measures for dental problems.
The categorization of subjects in our study was done in a different manner from ECOHIS.  The reason for this was that while ECOHIS had been developed using a single age group, that is, 5-year-old. Pahel et al.  had classified these subjects according to the number of decayed or treated teeth. However, if we had adopted a similar method, then a 3-year-old child with four decayed teeth would have been comparable to a 5 year old with the same number of decayed teeth. It has already been shown that the effects of ECC are more devastating if they occur earlier as it can cause loss of function as well as esthetics leading to poor eating habits and low self-esteem. Thus, it was decided that AAPD definition of ECC and severe ECC will be used for the purpose of the classification. Thus we divided the children based on presence and severity of ECC into three categories based on their age and number of decayed, missing and filled teeth as per AAPD definition  of ECC and severe ECC.
Parents of children who had poor oral health as indicated by caries status had higher scores in our study than in children without caries. Moreover the higher the number of carious teeth, the higher was the OH-ECQOL score with a significant difference in the scores between the three groups [Table 5] and [Table 6].
A majority of our questions were derived from CHQ, ITQOL, CPQ and ECOHIS as explained above. Thus our findings of poor OHRQoL indicated by higher scores on OH-ECQOL among children with poorer oral health are similar to those found using the CHQ and the ITQOL when comparing general health with QOL and also similar to relationship between poor oral health with OHRQoL by Jokovic et al.,  Pahel et al.,  Lee et al.,  Li et al.,  Filstrup et al.,  providing additional support for the relationship between dental status and HRQoL.
Internal consistency reliability
This describes how well each item in a group is related to others in the group. If a child has a high score in the oral symptoms domain then he/she should have a high score in the other categories as well. The value of Cronbach's alpha for OH-ECQOL was 0.862 indicating good internal consistency.  The mean value of Cronbach's alpha was 0.7185 for various subsets within the child impacts section and 0.7222 between various items in the family impacts section indicating good internal consistency reliability. The value of Cronbach's alpha as reported in our study is slightly lower than that reported by Jokovic et al.  and Pahel et al.  The reasons for this are due to lack of awareness amongst Indian parents about oral health of their children as well as lack of resources often sufficient emphasis might not be placed on oral health. Parents often attribute the child's discomfort to other issues rather than oral health. Moreover the lack of knowledge might result in parents not bothering to take the child for preventive or curative visits leading to lower impact on family in terms of emotional distress or financial impacts.
Test retest reliability
As evidenced by the value of ICC, it indicated almost perfect agreement between the first and second assessment.  This is similar to that obtained for ECOHIS  and CPQ 11-14 . 
This scale is the first of its kind for an Indian population. Moreover, the scale covers a vast range of age (24-71 months) as compared to ECOHIS and SOHO-5, which were designed only for 5-year-old children. This questionnaire was developed in local language that can be easily understood by the parents.
| Limitations|| |
The study sample constituted patients reporting to the hospital OPD. This does not constitute the entire population. Thus, this tool needs to be tested in a population-based field study as well. Moreover, the Cronbach alpha value was in an acceptable range only. This needs to be tested further. Longitudinal studies should be performed to determine the longitudinal construct validity and responsiveness of OH-ECQOL and minimal clinically important difference that essentially means the threshold for measuring improvement in OHRQoL as reported by the patient or his family.
| Conclusion|| |
The tool OH-ECQOL (Oral Health related Early Childhood Quality of Life) is a valid and reliable tool for assessing the OHRQoL in preschool North Indian children. It also indicates that ECC causes a substantial impact on the functional and psychological well-being of both the affected child and his/her family.
| Acknowledgment|| |
We wish to acknowledge the support of Dr. Navneet Grewal, Dr. Balaji Kathenani, Dr. Steven Rodrigues, Dr. Richa Khanna, Dr. M. S. Muthu, Dr. Tripti Rai, Dr. Namrata C. Gill, Dr. Vartika Kathuria, Dr. Gulsheen Kocchar, Dr. Tanupriya Gupta for their inputs in item reduction. We also wish to acknowledge Dr. Gauri Kalra (Ex. research Associate), Dr. Rajath (senior research fellow) and Dr. Arpit (Senior Resident) at CDER, AIIMS for their efforts in statistical analysis and editing the manuscript.
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Jatinder Kaur Dhillon
Department of Pedodontics and Preventive Dentistry, Maulana Azad Institute of Dental Sciences, New Delhi
Source of Support: None, Conflict of Interest: None
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]
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