A preliminary cross-cultural validation of the Pidgin version of the Rosenberg Self-esteem Scale and the leprosy-adapted Internalized Stigma of Mental Illness Scale among persons affected by leprosy in Southern Nigeria

Background Self-esteem and internalized stigma are important patient-reported outcomes. We describe the cross-cultural validation and adaptation of the Pidgin version of the Rosenberg self-esteem scale (P-RSES) and the leprosy-adapted Internalized Stigma of Mental Illness Scale (P-ISMI) in Cross River, Southern Nigeria. Methods The cultural equivalence of the instruments, including their conceptual, item, semantic, and operational equivalences, was evaluated using qualitative methods. A cross-sectional study of 56 participants with Hansen’s disease in Cross River, Southern Nigeria, was undertaken to assess the measurement equivalence of the tools. Results The conceptual, item, semantic, and operational equivalences of the Pidgin version of the P-RSES and P-ISMI scales showed adequate fit with all items identified as important in the context of the Pidgin-speaking population. There was a negative inverse correlation between the mean total scores of the P-RSES and the P-ISMI scale (r = −0.57; p < 0.001), confirming the construct validity of the two scales. The exploratory factor analysis for the scales indicated a good fit as a one-dimensional scale. The Cronbach’s alpha values were 0.82 and 0.95 for the P-RSES and P-ISMI scales, respectively. The test-retest reliability coefficient for the P-RSES and the P-ISMI scale was 0.98 and 0.67, respectively. There were no floor or ceiling effects in the distribution of the responses to the P-RSES and the P-ISMI scale. Conclusion The P-RSES and P-ISMI scales are reliable and valid instruments for the assessment of self-esteem and internalized stigma, respectively, in the Pidgin-speaking population of Nigeria.