The reliability of a survey question on television viewing and associations with health risk factors in US adults.

Research into the accuracy of self-reported measures used to quantify physical inactivity has been limited. The purposes of the current report were to examine the reliability of a survey question assessing time spent watching television and to describe associations between television watching and physical activity and health risk factors. Data from this cross-sectional investigation were obtained from a study designed to evaluate a physical activity module for potential use in the 2001 Behavioral Risk Factor Surveillance System. Participants were 93 men and women (aged 45.9 (15.4) years) who answered the question pertaining to television watching during an initial visit and three follow-up visits to the study center. Intra-class correlation coefficients (ICCs) between administrations of the survey question were used to assess test-retest reliability. Spearman rank order correlation coefficients were used to examine the associations of television viewing with physical activity and health risk factors. The test-retest reliability of the television-watching question suggested moderate agreement (ICCs of 0.42 and 0.55 over a 3-week and 1-week period, respectively). After adjustment for age and sex, reported television-watching hours were positively associated with BMI (P = 0.0002), percentage fat (P = 0.0001), and light-intensity physical activity (P = 0.006) and negatively associated with cardiorespiratory fitness (P = 0.004) and moderate-intensity and hard-intensity physical activity (P = 0.03 and P = 0.003, respectively). Increased time spent in sedentary behaviors has been identified as a major modifiable risk factor in the development of chronic diseases and conditions. The single-item survey question evaluated in this study was shown to be a reliable measure of television watching and was associated with physical activity and health risk factor outcomes.