IPAQ environmental module; reliability testing

The physical environment has emerged as a potential correlate to physical activity, and altering the environment could be one way to increase physical activity on a population level. The aim of the present study was to assess the test-retest reliability of the Swedish version of an environmental instrument developed for population-based studies. The study population was recruited from a larger study performed at the same time. A random sample of Swedish adults, age 18-74, was invited to participate in the reliability testing of 17 questions regarding the local physical environment. The questions addressed variables such as presence of sidewalks, bike paths and recreational facilities as well as questions regarding aesthetic, social and safety attributes. A total of 98 subjects completed the test and retest questionnaires. Overall percent agreement ranged from 55.1-92.9%. Intraclass correlation (ICC) for the total sample ranged from 0.36-0.98. The questions regarding motorized vehicles produced the highest total reliability score (ICC=0.98) and the question regarding safety from crime during the day produced the lowest (ICC=0.36). Small differences were seen between men and women for a few variables, but no apparent pattern was identified. The test-retest of the Swedish version of the environmental module resulted in substantial agreement for most variables. The instrument showed an acceptable reliability and can therefore be used in future studies regarding local environmental attributes and physical activity in Sweden.