Test reliability and stability of children's cognitive functioning.

This study addresses the test reliability of a screening test and stability of children's cognitive functioning. Children aged 5 to 8 years in western Sydney were assessed on three occasions. The first assessment provided a baseline, with the second assessment at 2-, 4-, or 12-week intervals. The final assessment was 4 weeks later. Indicators of reliability and stability suggested that a distinction can be made between test reliability and the phenomenon (cognitive functioning) stability Cognitive functioning was assessed using the School-Years Screening Test for the Evaluation of Mental Status (SYSTEMS). The findings have implications for indicators of reliability and stability of cognitive assessments in developmental research and clinical practice.