Translation and validation of Hindi version of Oral Health Impact Profile-14

Abstract

Title of the Study:

Validation of Hindi Version of Oral health Impact Profile (OHIP-14).

Aim:

To validate the Hindi version of OHIP-14.

Settings and Design:

The study was carried out in K.M. Shah Dental College & Hospital, Vadodara.

Materials and Methods:

OHIP-14 was translated into Hindi language.102 participants were given English as well as Hindi versions of OHIP-14.

Statistical Analysis Used:

Individual question were analyzed using Pearson Chi-Square test, Likelihood Ratio test and Linear-by-Linear Association test. The entire questionnaire in English and Hindi language were comparatively analyzed using Unpaired T test & Pearson correlation coefficient test.

Results:

All the 14 questions showed no statistically significant difference between the English OHIP-14 and the translated Hindi version of OHIP-14. Results of Unpaired T test (P = 0.61) were statistically insignificant. Pearson Correlation coefficient test was 0.963 suggesting that the translated Hindi version was highly correlated to the original English version.

Conclusion:

The translated Hindi version of OHIP-14 is hence established as a valid tool for conduction of oral health related & quality of life surveys in Hindi language which is the most commonly used language in the Indian subcontinent.

INTRODUCTION

Knowledge of the extent of periodontal disease gives a clinical indication of the experience of periodontal problems, but it does not necessarily reflect the problems that people experience as a result of their dentition. There are differences between clinician's and the public's evaluation of oral health. For example, dentists often appear to be most concerned about the integrity of previous dental work, whereas patients often seem most concerned with the appearance of their teeth.

The capacity of dental clinicians and researchers to assess oral health and to advocate dental care has been hampered by limitations in measurements of the levels of dysfunction, discomfort and disability associated with oral disorders. The purpose of the Oral Health Impact Profile (OHIP) is to provide a measure of the social impact of oral disorders, and it draws on a theoretical hierarchy of oral health outcomes.[1]

The aim of this index is to provide a comprehensive measure of self-reported dysfunction, discomfort and disability arising from oral conditions. It is based on locker's adaptation of the World Health Organization's (WHO) classification of impairments, disabilities and handicaps.[2] In the WHO model, impacts are organized linearly to move from a biological to a behavioral to a social level of analysis.[3] Slade and Spencer adapted this by proposing seven dimensions of impact of oral condition. Each of the seven dimensions in the original scale was assessed from questions on the type of problems experienced (a total of 49 questions).[1]

Any quality of life (QoL) assessment tool needs to be validated in the language of the participants to whom it is administered. A thorough search of the literature did not yield any study on the Hindi version of OHIP-14 to the best of our knowledge. The present study has tried to establish a Hindi version of OHIP-14 to evaluate the impact of oral health. This Hindi version would be helpful in general dentistry by evaluating the impact of other oral conditions on the QoL. Thus, this Hindi version of OHIP-14 would be useful to assess the impact of oral heath on QoL of dental patients In India, who understand Hindi language.

SUBJECTS AND METHODS

Prior permission of the institutional ethics committee was taken before initiation of this study. The OHIP, comprising 14 questions that are destined to influence the oral affections on the quality of social, psychic and physiological life was used. The answers offered by the subjects were evaluated in the following manner: 0 = never, 1 = hardly ever, 2 = occasionally; 3 = fairly often; 4 = very often. Thus, the negative impact was appreciated through the answers fairly often and very often, while a positive impact was determined by the answers: Never, hardly ever, and occasionally.

A bilingual dentist did translation of the questionnaire from English to Hindi language. Another independent bilingual dentist translated the Hindi questionnaire back to English language. The differences were noted, and the differences were sorted out by involving both the bilingual translators. Thus, a final Hindi version was arrived at which was used to carry out the study. A registered notary of government of India certified this questionnaire to be a true translation from English language to Hindi language.

A Hindi version of OHIP-14 was given to 102 participants who fulfilled the inclusion and exclusion criteria. The inclusion criteria were patients who could understand Hindi and English language and who were above the age of 18 years. The exclusion criteria were patients who were unwilling to take part in the study. The same patients were also given the English OHIP-14 questionnaire. The data collected were subjected to statistical analysis for validity of the questionnaire.

RESULTS

Results were analyzed for an individual question using Pearson Chi-square test, likelihood ratio test and linear-by-linear association test.

Results for the entire questionnaire in English and Hindi language were comparatively analyzed using paired t-test and Pearson correlation coefficient test.

Baseline characteristics were as follows

• 92.2% of the study participants belonged to the age group of <30 years

• The gender ratio was equal for males to females. Male participants were 50%, and female participants were 50%

• 57.84% of the participants were students

• 54.9% of participants had not undergone any dental treatment prior to the current visit

• Out of the ones who had undergone previous dental treatment, 80.4% had undergone scaling in the previous dental visits.

Comparative results of individual questions of Oral Health Impact Profile-14 questionnaire were as follows

All the 14 questions showed no statistically significant difference between the English OHIP-14 and the translated Hindi version of OHIP-14.

Comparative results of the entire Oral Health Impact Profile-14 questionnaire were as follows

• Results of unpaired t-test (P = 0.61) were statistically insignificant [Table 1]

• Pearson correlation coefficient test was 0.963 [Table 2].

Table 1.

Unpaired t-test (group statistics)

Table 2.

Correlation

The results of this study showed that the translated Hindi version of OHIP-14 was a valid tool.

DISCUSSION

In the present study, we found the Hindi version of the OHIP-14-P to be a valid and reliable instrument, similar to the original version.[1] In this study a rigorous translation procedure was followed to achieve a culturally equivalent, instrument-targeted semantic and conceptual agreement between the original and the translated version. A recognized Notary of government of India verified Hindi translation to be a legal translation. The cross-cultural adaptation of the quality of measures can be problematic.[4,5] Guidelines have been published to facilitate the development of conceptually equivalent QoL measures.[6,7] The present study followed standard procedures for the translation, which have been frequently used for the translation of both QoL and oral health-related quality-of-life (OHRQoL) measures.

In order to measure the oral health-related QoL of Indians, ideally an instrument that is culturally sensitive has to be developed. However as it is a costly and time-consuming exercise, an alternative approach would be to translate an existing instrument and adapt it for use among Indian population. The present study, therefore, attempted at validating a Hindi translation of the OHIP-14 scale.

Information about the psychometric properties of the English-language OHIP-14 is scarce, but a couple of studies have shown that its validity and reliability are similar to that of OHIP49 that has well-established properties.[1,8]

Intercultural process of adaptation of OHIP-14 from English into Hindi was simple and the comparison between the original OHIP-14 and translated Hindi version did not create differences in meaning or context. Several studies have shown the reliability and validity of the tested questionnaire in the adult population. However, it should be noted that this instrument has not been extensively used either in adolescents nor in children populations.[9] Only three studies have been conducted worldwide[10,11,12] and only one has performed translation and cultural adaptation of the instrument.[13]

The aim of this study was to validate a translated Hindi version of OHIP-14. The sample included 102 participants who visited a dental hospital for receiving dental treatment.

In the present study the results were analyzed for an individual question using Pearson Chi-square test, likelihood ratio test, linear-by-linear association test. We found that there was no statistical significant difference between the English and Hindi questions when they were analyzed individually. This established the validity of the individual question of OHIP-14 in Hindi language.

Comparative results of the entire OHIP-14 were analyzed by unpaired t-test, (P = 0.61) was found to be statistically insignificant. Pearson correlation coefficient (0.963) was high correlating the two versions. A high relationship between the English and Hindi version of OHIP-14 questionnaires was found. A minimum of 80% correlation is required to establish the validity of the newer translated version. In our study, we found a 96.3% correlation between the English and Hindi versions of OHIP-14.

No consensus exists about which criteria should be used to assess the reliability, validity and responsiveness. However, the unpaired t-test and correlation coefficient used in this study are sufficiently showing the validity of Hindi version OHIP-14.

The stability of the Brazilian OHIP-14 was good and similar to that of the Chinese OHIP-14 but slightly lower than that of the German version of the instrument. It is important to note that, as the reliability of a measure is intimately linked to the population to which it is applied, the value of the reliability coefficient obtained reflects the homogeneity of our study population with respect to the impact of oral problems on OHRQoL. Therefore, one can expect that if the same questionnaire is to be applied to a more heterogeneous group of subjects, a greater reliability coefficient can be obtained.

On the contrary, results of the present study are consistent with those found by others,[1,14] it is reasonable to suggest that the test–retest reliability of OHIP-14 might be improved by the introduction of items that would result in average scores further from the minimum possible, thus reducing its floor effect which limits its ability to discriminate between groups.[1]

In various studies the investigators have agreed with the approach that physical disability, functional limitations and psychological discomfort have the highest correlation with oral health and an important impact in QoL,[10,11,12] confirmed in this study.

Another point worth noting is that, during the interviews, a few respondents were in doubt if they should answer “never” or “hardly ever” when a given impact was experienced once or twice during the period of reference. Considering the acute nature of oral problems more often experienced by younger subjects, it might be useful to add to OHIP-14 the response option “once/twice” as done by Jokovic et al. in the “Child Oral Health Quality of Life Questionnaire”.[9] In future research, it can be seen if adding that response option to OHIP-14 would contribute to the improvement of the reliability of the instrument when applied to different populations.