The performance of normal and mentally subnormal Zambian Children on two Intelligence tests and a conservative test

This study evaluates the construct validity of three non¬verbal tests - Panga Munthu, Porteus Maze and Nonverbal Conservation Tests - to be used in identifying and assessing the mentally sub¬normal children in Zambia. The subjects for this study included average normal school children aged 7-8 years, 9~10 years and 11-12 years; 11-12 year-old Bright and Dull normal children, and 9-13 year-old moderately (MSN) and severely subnormal (SSN) children in Lusaka. The results show that the three tests differentiate the three age groups, and also the normal and the subnormal children. Panga Munthu and Porteus Maze tests differentiate the two subnormal groups but not the three groups of normal children. The conservation test separates the Dull from the Average and Bright children, but not the MSN from the SSN children. Since there is also some significant positive correlation among the tests, it is recommended that with some modifications the three tests may be included in a battery of clinical tests.