Translation and validation of the Igbo version of the Warwick–Edinburgh Mental Well-being Scale in Nigeria

Abstract

There is growing international interest in the assessment of mental well-being. This study offers lessons learned from the field in the assessment of the validity and the reliability of the Igbo version of the Warwick–Edinburgh Mental Well-being Scale (Igbo-WEMWBS) among adult Igbos in areas affected by Hansen’s disease in southern Nigeria. The World Health Organization methodologies were applied in translating the WEMWBS into Igbo. The psychometric properties and validity of the Igbo-WEMWBS were analysed. Of the 100 participants enrolled, 74.0% (n=74) were ≤40 y of age and 55.0% (n=55) were females. The total score of the new scale had a mean of 54.05 (95% confidence interval 52.31 to 55.79) and a range of 30–70. It was shown that a one-factor solution was optimal for the Igbo-WEMWBS. The Cronbach’s α coefficient was 0.83 for the Igbo-WEMWBS. The stability of the Igbo-WEMWBS was found to be very high (r=0.96). There was a moderate correlation between the Igbo-WEMWBS and the World Health Organization-5 Well-Being Index and World Health Organization Disability Assessment Schedule. A cut-off score of ≤48.50 was found to be ideal for diagnosing very low mental well-being using the Igbo-WEMWBS. The Igbo-WEMWBS was found to be reliable and valid and can be used to assess mental well-being related to leprosy in the Igbo-speaking population of Nigeria.

Introduction

The psychological and societal consequences of leprosy have been widely researched, in particular in relation to disability and stigma.¹ A recent systematic review revealed that multiple psychiatric morbidities have been identified among leprosy-affected persons, including depression, anxiety disorders and suicide (attempts).² Thus leprosy patients may have very low mental well-being.

The Warwick–Edinburgh Mental Well-being Scale (WEMWBS) was developed to meet the need for a psychometrically robust measure that would enable monitoring of mental well-being in the general population and the evaluation of projects, programs and policies that aim to improve mental well-being.³ The tool comprises 14 items that relate to an individual’s state of mental well-being (thoughts and feelings) in the previous 2 weeks.

To ensure cultural and environmental suitability in many climes, WEMWBS has been translated and validated in Nepal and used to assess mental well-being of patients with leprosy.⁴ However, the WEMWBS has not been validated in any of the local languages in Nigeria. This article offers lessons learned from the field in the assessment of the validity and reliability of the Igbo version of the WEMWBS (Igbo-WEMWBS) among Igbos affected by Hansen’s disease in southern Nigeria.

Methods

Study design and area

This study was a cross-sectional survey carried out from November to December 2020. The populations of this study were all volunteering adults (both male and female), ≥18 y of age who met the inclusion criteria for participation in the study and were sourced from conveniently sampled leprosy-endemic communities in Anambra State in southern Nigeria.

Inclusion criteria

The participants of the study were adults (≥18 y of age) who live in communities where leprosy has been notified in at least the past 2 years and are well oriented in time, place and person and who speak and understand both English and the Igbo language.

Research instruments

Interview form

The form was used to collect sociodemographic data (age, education level, employment status, monthly family income, type of residence and marital status).

WEMWBS

The WEMWBS is a 14-item scale with five response categories with a total score ranging from 14 to 70. The items are all positively worded. Respondents are required to describe their experience of each statement over the past 2 weeks using a 5-point Likert scale (none of the time, rarely, some of the time, often, all of the time). The overall WEMWBS score is calculated by summing the scores for each item, with equal weights. A higher WEMWBS score therefore indicates a higher level of mental well-being.³

The WEMWBS scale was translated into Igbo in line with recommendations set forth by the World Health Organization (WHO) for the translation and adaptation of scales, which includes forward translation, back translation, expert panel review, pretesting and cognitive interviewing and final version.

World Health Organization-5 Well-Being Index (WHO-5)

The WHO-5 questionnaire consists of five positively worded items about a respondent’s feeling during the preceding 2-week period. Each item is rated on a 6-point Likert-type scale of 0–5, with 0 indicating the lack of positive feelings during the preceding 2 weeks and 5 indicating consistent positive feelings. The raw scores are transformed into a scale ranging from 0 to 100. Scores ≤50 are indicative of a poor emotional state and the need for further testing. This was used during the initial validation of the English version of the WEMWBS.³

12-item General Health Questionnaire (GHQ-12)

This is a well-known and extensively validated screening questionnaire for assessing probable mental illness. It is a reliable and valid measure of psychological distress and general well-being.⁵ The GHQ is short and easy to complete, containing only 12 items. As was found elsewhere, the optimal cut-off for the GHQ-12 was 4. A cut-off score of 4+ is often used, with the 4+ group being more likely to have a diagnosable mental illness.⁵ This was also used during the initial validation of the English version of the WEMWBS.³

World Health Organization Disability Assessment Schedule (WHODAS) 2.0

This questionnaire asks about difficulties due to health conditions experienced by a person. The WHODAS 2.0 instrument consists of 12 items covering different disability domains over the previous 30 d. Each of the 12 items is rated on a 5-point Likert-type scale with a score of 0–4, where 0 means no disability and 4 means extreme or complete difficulty. The total score is the sum of the 12 subscores, ranging from 0 to 48, with lower scores indicating lower disability and better functioning.

Sampling and data collection

A purposive sampling technique was used in this study. The study included two visits. During the first visit a questionnaire of sociodemographic data, the Igbo-WEMWBS, WHO-5, GHQ-12 and WHODAS 2.0 were administered to 100 consenting adult community members. The second visit was carried out 2 weeks after the first visit, where the Igbo-WEMWBS was readministered to consenting participants.

Statistical analysis

The data were analysed with SPSS for Windows version 27 (IBM, Armonk, NY, USA). Descriptive statistics were used to describe the characteristics of the participants. Exploratory factor analysis was used to assess the construct validity of the Igbo-WEMWBS. The internal consistency of the tool was assessed via Cronbach’s α coefficient. The test–retest reliability of the tool was assessed using Pearson’s correlation coefficient. Validity was assessed using established methods. The significance level of tests was set at p<0.05 (two-sided tests).

Results

A total of 100 respondents were administered the Igbo-WEMWBS, 55 (55.0%) of them were females and the mean age was 34.5±14.4 y. The sociodemographic characteristics of the participants is as shown in Supplementary Table 1. The total score of the Igbo-WEMWBS had a mean of 54.05 (95% confidence interval [CI] 52.31 to 55.79) and a range of 30–70. The distribution of the total score was normal, with kurtosis −0.34 and skewness −0.12 (Figure 1). Supplementary Table 2 shows the mean scores for all 14 items on the new scale. The Cronbach’s α coefficient for the Igbo-WEMWBS for the study population was 0.83 (Supplementary Table 3).

Figure 1.

Responses on the Igbo-WEMWBS among the study participants (N=100).

Test–retest reliability

Test–retest reliability was analysed for all 100 participants who were administered the Igbo-WEMWBS 2 weeks apart. The mean Igbo-WEMWBS scores at the first and second visit were 54.05±8.75 and 53.72±8.95 respectively. Pearson’s correlation coefficient of the scores was 0.96 (95% CI 0.94 to 0.97) with p<0·001 indicating excellent reliability.

Validity

Exploratory factor analysis of the Igbo-WEMWBS was performed among survey participants. The Kaiser–Meyer–Olkin (KMO) measure of sampling adequacy was 0.81 and Bartlett’s test of sphericity was significant (χ²=377.44, p<0.001), indicating the suitability of the data for factor analysis. Factor analysis confirmed a single underlying factor to the scale, shown in the sharp ‘elbow’ of the screen plot (Supplementary Figure 1).

There was a significant correlation between the overall Igbo-WEMWBS score and total WHO-5 score (r=0.48 p<0.001). Also, there was significant correlation between the overall Igbo-WEMWBS score and total WHODAS 2.0 score (r=−0.35 p<0.001). This indicates the Igbo-WEMWBS has significant concurrent validity with both tools.

Using the GHQ-12 cut-off of >4, 12 (12.0%) of the patients assessed using the Igbo-WEMWBS were deemed to have very low metal well-being while 88 (88.0%) were normal. Analysis of the receiver operating characteristics curve indicated that the Igbo-WEMWBS cut-off score of ≤48.50 was the best for identifying very low mental well-being with sensitivity and specificity of 0.66 and 0.56, respectively. The area under the curve was 0.60 (95% CI 0.55 to 0.73), which was statistically significant (p=0.001).

Floor and ceiling effects

No floor or ceiling effects were identified for the Igbo-WEMWBS.

Conclusions

The study has some limitations. The study was performed among samples of an Igbo-speaking population and may not be generalisable to the general population who speak other languages in Nigeria. Second, we performed the predictive validity assessment using the GHQ-12 as an instrument to diagnose very low mental well-being in order to obtain a suitable cut-off value for the WEMWBS. This may not be ideal as the GHQ-12 itself has a sensitivity of 72.2% to diagnose depression and 59% to diagnose generalised anxiety disorder. The gold standard instrument for making a psychiatric diagnosis is the Composite International Diagnostic Interview. However, the instrument is not suitable for field-based studies because it requires expertise in its administration. Our approach allows for the use of a screening tool under routine field conditions.

Despite these limitations, the Igbo-WEMWBS was found to be a reliable and valid measure with good psychometric properties. Therefore the scale may be useful not only for empirical research but also for the monitoring of changes in mental well-being in intervention studies and could be useful during educational, preventive or social activities. Further research with a larger sample is needed to assess its use in groups with different health status, such as communicable and non-communicable diseases.

Authors’ contributions

NE, KNU, AO, EO, FC, JC, CN, AM, DE, PO, MN, CE and NMO conceived the study, designed the study protocol, collected data, performed data entry, carried out the data analysis and interpretation, critically revised the manuscript for intellectual content and read and approved the final manuscript. NE and KNU drafted the manuscript and are guarantors of the article.

Funding

This work is supported by the Leprosy Research Initiative Foundation (grant 708.20.15/LRI). The funding source had no role in the study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the article for publication.

Competing interests

None declared.

Ethical approval

The study participants were told about the study objectives and were informed that their involvement was voluntary and all their information would be kept confidential. They subsequently provided written informed consent and the questionnaires were administered to them by trained research assistants. Ethical approval for the study was granted by the Health Research and Ethics Committee of University of Nigeria Teaching Hospital, Ituku Ozalla, Enugu (NHREC 0501-2008B).

Data availability

The data presented in this study are available upon request to the corresponding author.