Abstract
(1) Background: People who are diagnosed with schizophrenia experience a reduced average lifespan compared to the general population. Also, approximately 85% of individuals with schizophrenia have chronic physical illnesses. Moreover, 60% of premature deaths in this population could be prevented through the adoption of health-promoting behaviors. (2) Methods: This study involved the recruitment of 220 participants from an outpatient clinic in Seoul, South Korea. Inclusion criteria comprised adults aged 19 years or older with a confirmed diagnosis of schizophrenia. Data collection occurred between 25 May 2021 and 2 August 2021, utilizing self-report questionnaires. A total of 202 responses were subjected to analysis using SPSS 23.0 and AMOS 23.0. (3) Results: The findings indicate that the final model is characterized by the following values: Normed x(2) = 2.240, RMSEA = 0.079, TLI = 0.926, x(2) = 562.2 (p < 0.001), AGFI = 0.830, GFI = 0.814, and CFI = 0.938. Notably, health knowledge did not exhibit a significant direct or overall impact on health-promoting behaviors. Conversely, social support and psychiatric symptoms demonstrated direct, indirect, and total effects on health promotion through an intervening variable. This study underscores the pivotal role of self-efficacy as the most influential factor affecting health-promoting behaviors in individuals with schizophrenia. (4) Conclusions: enhancing self-efficacy emerges as a crucial element in the design and implementation of intervention programs aimed at improving health-promoting behaviors in individuals with schizophrenia.