Epistemological Foundations of Assessment in Nigerian Special Education: Towards a Decolonised Practice

This doctoral study critically examines the epistemological foundations of assessment practice in Nigerian special education and develops proposals for decolonising assessment in ways that are epistemologically honest, culturally valid, and practically responsive to Nigerian contexts. Assessment in special education, encompassing diagnostic evaluation, curriculum-based measurement, functional assessment, and transition assessment, draws on instruments, frameworks, and conceptual models developed almost exclusively in Western contexts. When applied in Nigeria without critical adaptation, these tools risk producing invalid findings, misidentifying children, and reinforcing deficit orientations derived from cultural assumptions that differ fundamentally from those of Nigerian communities. The study employs a critical theoretical methodology in two phases. Phase one conducts a comprehensive epistemological critique of ten internationally used assessment instruments currently applied in Nigerian special education, examining the cultural assumptions embedded in their normative samples, item content, administrative procedures, and interpretive frameworks. Phase two engages forty assessment practitioners, disability researchers, and community knowledge holders across all six geopolitical zones in collaborative epistemological dialogue workshops aimed at generating principles and prototype practices for decolonised assessment. Findings are synthesised into an original theoretical framework, the Culturally Responsive Assessment in Special Education Framework, along with practical guidelines for its implementation. The study makes original contributions to assessment theory, disability studies, and post-colonial education research. Keywords: epistemology, decolonised assessment, special education, Nigeria, cultural validity.