A Critical Examination of Decolonising Psychological Assessment in Nigeria: Developing Culturally Valid Cognitive Assessments for Hausa and Igbo Adults

Psychological assessment in Nigeria continues to rely predominantly on instruments developed in Western contexts, creating fundamental construct validity threats when these tools are applied to culturally distinct Nigerian populations with different cognitive schemas, problem-solving styles, and linguistic frameworks. This study undertakes the systematic development and validation of culturally valid cognitive assessment batteries for Hausa and Igbo adults through a decolonising psychological science methodology. Phase 1 applies community-based participatory research methods including 50 focus groups in Kano, Sokoto, Enugu, and Anambra to identify indigenous cognitive competence constructs. Phase 2 develops battery items through iterative expert panel review and cognitive interviewing with 80 community members. Phase 3 validates the Hausa and Igbo Cognitive Assessment Batteries in independent samples of 300 Hausa and 300 Igbo adults, evaluating internal consistency, test-retest reliability, confirmatory factor structure, and concurrent validity with educational achievement. Phase 4 examines demographic effects and establishes preliminary normative data. Decolonial Psychology Framework by Bulhan, Wober's Culture-Specific Cognitive Theory, and Vygotsky's Sociocultural Theory of Cognition provide the theoretical scaffolding. The original contribution is the first systematically developed culturally valid cognitive assessment battery for Hausa and Igbo adults in Nigeria, advancing decolonising assessment practice across West Africa. Keywords: cognitive assessment, decolonising psychology, Hausa, Igbo, cultural validity.