Relationship Between Self-report and an Objective Measure of Television-viewing Time in Adults

• Published in: Obesity (Silver Spring, Md.) Md.), 2010-06, Vol.18 (6), p.1273-1275
• Main Authors: Otten, Jennifer J, Littenberg, Benjamin, Harvey-Berino, Jean R
• Format: Article
• Language: English
• Subjects: Adult; adults; Aged; Body Mass Index; confidence interval; Female; Humans; Interviews as Topic; Life Style; Male; Middle Aged; obesity; Reproducibility of Results; Research Design; Self Disclosure; Television; Time Factors; Young Adult
• ISSN: 1930-7381; 1930-739X
• DOI: 10.1038/oby.2009.371

This study compared self-reported television (TV)-viewing time with an objective measure obtained by an electronic TV monitor. As part of a larger study, 40 overweight and obese adults (BMI: 31.7 ± 5.4 kg/m2; 53% obese; mean age 41.4 ± 13.0) self-reported TV-viewing time at study entry as the response to the question, “How many hours do you watch TV per day, on average?” Objective TV-viewing time was measured in min/day over 3 weeks/subject using electronic monitors. Self-reported viewing time was 4.3 ± 1.3 h/day (mean ± s.d.) (range: 3.0–8.0 h/day) vs. 4.9 ± 2.6 h/day (0.8–13.3 h/day) recorded by the electronic TV monitor. Subjects underestimated their viewing time by 0.6 ± 2.3 h/day (95% confidence interval = −1.34, 0.13), or 4.3 h/week. Slightly over half of the subjects (58%) underestimated their viewing time; 47.5% were within 1 h/day, and 72.5% were within 2 h/day of self-reported viewing time. Large errors were rare in this group, suggesting that a simple self-report measure of TV time may be useful for characterizing viewing behavior, although objective measurement adds precision that may be useful in certain settings.