Psychometric Evaluation and Cultural Adaptation of the General Health Questionnaire-28 for Use in Northern Nigerian Clinical Settings

The General Health Questionnaire-28 is one of the most widely used screening instruments for psychological distress in clinical and community settings internationally, yet its psychometric properties have not been rigorously evaluated in the distinct sociocultural and linguistic context of Northern Nigeria. This study evaluates the reliability, validity, and cultural appropriateness of a Hausa-adapted version of the GHQ-28 for use in clinical settings across North West and North East Nigeria. A cross-sectional validation design is applied to 320 adults attending primary healthcare centres in Kano, Sokoto, and Maiduguri, selected through systematic sampling. The Hausa GHQ-28 is administered alongside a structured diagnostic interview using DSM-5 criteria as the gold standard. Internal consistency, test-retest reliability, confirmatory factor analysis, convergent validity with the PHQ-9, and sensitivity and specificity against the diagnostic interview are computed. Available cross-cultural psychometry literature from Northern Nigeria identifies conceptual non-equivalence of somatic complaint items and inadequate translation of depression-specific language as the primary psychometric challenges. The Classical Test Theory and Item Response Theory frameworks guide the validation analysis. Findings will identify items requiring cultural modification and establish normative cut-off scores for Northern Nigerian clinical use. Results will have direct utility for clinical psychologists and psychiatrists practicing in the North West and North East zones. Keywords: psychometric evaluation, GHQ-28, cultural adaptation, Northern Nigeria, clinical psychology.