Partitioning the Sleep Quality and Insomnia Severity among Earthquake Victims in the West of Iran: Cluster Prediction Based on Personality and Psychological Factors.

Background: We aimed to perform a cluster analysis on sleep quality and insomnia severity in addition to predicting the clusters based on personality traits, experiential avoidance, stress, anxiety, depression, and dysfunctional beliefs and attitudes about sleep.
Study Design: A cross-sectional study.
Methods: This study was conducted on earthquake victim in Kermanshah (western Iran) in 2017. Data collection began 15 d after the earthquake and lasted for 2 weeks. First, 1002 copies of the questionnaire were distributed and, finally, analyses were performed for 778 individuals. Data analysis was conducted using cluster analysis.
Results: Based on sleep quality and insomnia severity, four clusters were formed, and a correlation existed between some personality traits, psychological distress, experiential avoidance, and dysfunctional beliefs and attitudes about sleep with unhealthy clusters (P<0.05). The summary of the model showed the sufficient fit of the model (P<0.0005) and that it could predict 22.8%-42.4% of the variance of unhealthy clusters.
Conclusion: Dysfunctional beliefs and attitudes about sleep, experiential avoidance, stress, anxiety, depression, and personality traits could contribute to sleep problems and reduce sleep quality in earthquake victims.