Introduction
Although leprosy is curable since 1981, people affected by leprosy still experience stigmatisation and\ discrimination. The stigma towards people affected by leprosy may lead to a decreased quality of life.\ Few studies have focused on major depressive disorder as a comorbidity of leprosy. There is no simple\ and widely validated instrument that has been validated to diagnose depression among people\ affected by leprosy. For this study, the PHQ-9 was cross-culturally validated in Bahasa Indonesia. The\ PHQ-9 has been validated in other countries in Asia, however not in Indonesia or for people affected\ by leprosy.
Objective
The purpose of this study is to (A) perform a cultural validation of the PHQ-9 in Bahasa Indonesia and\ (B) to measure the depression status of people affected by leprosy with the validated PHQ-9.
Methods
This study took place in Central Java. The PHQ-9 was translated and back-translated and after that, 15\ semi-structured interviews and one focus group were conducted for assessing the conceptual,\ operational, item and semantic equivalence. After analysing the interviews, a refined version of the\ PHQ-9 was made. For the quantitative part, 114 people affected by leprosy and 54 control group were\ included to assess the measurement equivalence. Forty-nine people repeated the questionnaire one\ week later. The following psychometric properties were calculated using SPSS: internal consistency,\ construct validity, reliability, floor and ceiling effects, interpretability, cut-off score and the prevalence\ of depression.
Results
Two questions were adapted and after that all questions were considered relevant, comfortable and\ clear. The internal consistency was defined with Cronbach{\textquoteright}s alpha and 0.718. Floor and ceiling effects\ were not found. The reliability was measured with the repeated interviews. The intra-class coefficient\ was 0.713 (p\<0.001). For the construct validity, the Spearman correlation showed that there was a\ positive correlation between the total score of the PHQ-9 and the total score of the BDI-II. The means\ and standard deviations of the people affected by leprosy group and the control group showed that\ the PHQ-9 was able to distinguish between groups defined by gender, leprosy-related physical\ problems and visible signs of leprosy. A cut-off point of 10 was adopted on the basis of the original\ validation of the PHQ-9. The results showed a higher prevalence of depression in the people affected\ by leprosy group, but this was not significant.
Conclusion
The PHQ-9 is suitable to be used as a screening instrument of depression for people affected by leprosy\ and in Indonesia. The item, semantic and measurement equivalence are good.