Abstract
BACKGROUND: Television viewing is an important modifiable risk factor for childhood obesity. However, valid methods for measuring children's TV viewing are sparse and few studies have included Latinos, a population disproportionately affected by obesity. The goal of this study was to test the reliability and convergent validity of four TV viewing measures among low-income Latino preschool children in the United States. METHODS: Latino children (n=96) ages 3-5 years old were recruited from four Head Start centers in Houston, Texas (January, 2009, to June, 2010). TV viewing was measured concurrently over 7 days by four methods: (1) TV diaries (parent reported), (2) sedentary time (accelerometry), (3) TV Allowance (an electronic TV power meter), and (4) Ecological Momentary Assessment (EMA) on personal digital assistants (parent reported). This 7-day procedure was repeated 3-4 weeks later. Test-retest reliability was determined by intraclass correlations (ICC). Spearman correlations (due to nonnormal distributions) were used to determine convergent validity compared to the TV diary. RESULTS: The TV diary had the highest test-retest reliability (ICC=0.82, p<0.001), followed by the TV Allowance (ICC=0.69, p<0.001), EMA (ICC=0.46, p<0.001), and accelerometry (ICC=0.36-0.38, p<0.01). The TV Allowance (r=0.45-0.55, p<0.001) and EMA (r=0.47-0.51, p<0.001) methods were significantly correlated with TV diaries. Accelerometer-determined sedentary minutes were not correlated with TV diaries. The TV Allowance and EMA methods were significantly correlated with each other (r=0.48-0.53, p<0.001). CONCLUSIONS: The TV diary is feasible and is the most reliable method for measuring US Latino preschool children's TV viewing.