Construct validity of the PERF-FIT, a test of motor skill-related fitness for children in low resource areas

Background: Given the relationship between physical fitness and motor performance a test battery was developed that measures both components combined. Aim: Following the development of the Performance and Fitness (PERF-FIT) battery, this study investigated the construct validity with the ultimate aim of identifying attributes that discriminate between different levels of motor abilities and anaerobic or musculoskeletal fitness. Methods: In this cross-sectional study, 34 children with developmental coordination disorder (DCD) and 34 matched typically developing children participated (7-10 years). The PERF-FIT was used to examine known group validity. The PERF-FIT items were also compared to test items of well-known standardized tests to examine concurrent validity. Results: Concurrent validity was found to be of the expected low to moderate magnitude. Children with DCD were consistently found to have lower levels of motor skill-related fitness compared to typically developing children. Conclusion and implications: The PERF-FIT seems to be a valid test to measure movement skills, musculoskeletal fitness and agility in children between the ages of 7 and 10 years in low resourced communities. The test seems to discriminate between gross motor skills, and agility and power in children with and without DCD.