Tehran University of Medical Sciences Journal of Sleep Sciences 2476-2938 8 3-4 2026 07 26 67 71 Maryam Shahyad Department of Education and Counseling, Faculty of Literature, Humanities and Social Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran Nooshin Pordelan Department of Education and Counseling, Faculty of Literature, Humanities and Social Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran Mahdi Khasmohammadi Department of Education and Counseling, Faculty of Literature, Humanities and Social Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran 2024 08 04 2025 12 18 Background and Objective: With the rapid global growth of the elderly population, identifying factors associated with their psychological and social well-being has become increasingly important. This study aimed to compare sleep health, psychological hardiness, and social responsibility between community-dwelling older adults and nursing home residents. Materials and Methods: This causal-comparative (ex post facto) study examined differences between two naturally existing groups of older adults. A total of 120 participants (50 nursing home residents and 70 community-dwelling older adults) were recruited through convenience sampling. Data were collected using the Personal-Social Responsibility Questionnaire, the Sleep Health Scale (SHS) by Brandolim Becker et al., and the Kobasa Hardiness Scale. Data were ana-lyzed using SPSS software through descriptive statistics and independent samples t-tests with a significance level of 0.05. Results: The mean age of participants was 66 years. Sleep health scores were significantly higher among community-dwelling older adults (19.31 ± 3.65) than nursing home residents (15.72 ± 3.11) [t(118) = -5.65, P = 0.001]. Similarly, social responsibility was significantly higher in community-dwelling participants (36.33 ± 6.13) compared with nursing home residents (24.74 ± 5.14) [t(118) = -10.91, P = 0.001]. No significant difference was observed in psychological hardiness between groups (P = 0.41). Conclusion: The living environment appears to be associated with the sleep health and social responsibility of older adults, whereas psychological hardiness remains relatively stable across living conditions. These findings provide valu-able insights for policymakers and healthcare professionals in designing programs to improve the quality of life (QOL) in the older population. https://jss.tums.ac.ir/index.php/jss/article/view/297