Discrepancies Between Beliefs and Practices on Sleep as a Factor of Insomnia and Negative Feelings

Two online surveys were conducted in Japan to develop and validate the Sleep Belief-Practice Index (SBPI) scales, a pair of new scales designed to measure beliefs (SBPI-B) and practices (SBPI-P) on sleep and its environment. Their discrepancies (SBPI-D) were calculated as differences between SBPI-B and -P. In Survey 1 (N = 400), survey data of the pilot version of the scales were entered into an exploratory factor analysis to obtain a meaningful set of scale items. In Survey 2 (N = 2952), survey data were entered into a confirmatory factor analysis and then correlation analyses to confirm associations of SBPI-D with insomnia and positive and negative feelings. Furthermore, participants were categorized into four groups according to the degree and combination of sleep beliefs and practices to compare the status of insomnia and positive and negative feelings by the groups. As a result of factor analyses, we obtained 13 common item scales of SBPI-B and -P. SBPI-D was positively correlated with insomnia and negative feelings. In addition, the group with high-scoring beliefs in SBPI-B and low-scoring practices in SBPI-P showed the most severe insomnia and negative feelings among the four groups. These results suggest that the belief-practice discrepancy about sleep can explain one aspect of insomnia.