Validation of the Korean version of the Time Monitoring Behavior-10 (TMB-10) and its relationship with sleep effort...

We aimed to validate the Korean version of the Time Monitoring Behavior-10 (TMB-10) among individuals who complain of insomnia. In addition, we examined the relationship among sleep-related cognition, time-monitoring behavior, and insomnia severity.

We conducted an online survey among members of the general population who complain of insomnia. Data from 548 participants were analyzed. Participants' sleep-wake patterns and psychological status were assessed using rating scales, including the TMB-10, Insomnia Severity Index (ISI), Patient Health Questionnaire-9 (PHQ-9), Glasgow Sleep Effort Scale (GSES), and Adaptive Cognition and Behaviors about Sleep-6 (ACBS-6).

Exploratory factor analysis using Sample I (N = 271) determined a two-factor model for the TMB-10. Confirmatory factor analysis for the two-factor model revealed a good fit, as indicated by a comparative fit index of 0.996, Tucker-Lewis index of 0.995, root-mean-square error of approximation of 0.123, and standardized root-mean-square residual of 0.001. The internal consistency reliability of the Korean version of the TMB-10 was high (McDonald's omega = 0.940). The TMB-10 significantly correlated with sleep onset time (r = 0.26), sleep onset latency (r = 0.23), wake-up time (r = 0.11), desired time in bed (r = 0.12), ISI (r = 0.59), PHQ-9 (r = 0.45), GSES (r = 0.60), and ACBS-6 (r = -0.13; all p < 0.01). Linear regression analysis revealed that age (β = -0.09), ISI (β = 0.32), ACBS-6 (β = -0.08), and GSES (β = 0.39) were associated with the TMB-10. Adaptive sleep-related cognition was associated with improved, and sleep effort was associated with worsened insomnia severity, and time-monitoring behavior mediated the influence of adaptive sleep-related cognition and sleep effort on insomnia severity.

The Korean TMB-10 is a reliable and valid tool for assessing time-monitoring behavior. Time monitoring was correlated with greater insomnia severity, higher sleep effort, and less adaptive sleep-related cognition.