Questioning the validity of inquiry assessment in a high stakes Physical Sciences examination
Abstract
The South African science curriculum advocates an inquiry-based approach to
practical work. Inquiry is a complex and multifaceted activity involving both cognitive
and physical activity; thus, paper-and-pencil items do not provide the authentic
context for this assessment. This study investigates the construct validity of inquiryrelated
questions in three national Grade 12 Physical Sciences examinations. Clarity
about what is being assessed and how well a test samples a construct are critical
to validity. The analysis that was guided by Stobart’s conceptualisation of construct
validity revealed that, to a large extent, inquiry-related questions exhibited threats to
validity. The identified threats were categorised as contested validity, unclear validity
and construct irrelevance. The findings of this study suggest that greater attention
needs to be paid to the formulation of inquiry-related questions in written tests and
examinations.