LAUSR

AIM To systematically evaluate the available literature about overall levels of psychological capital among nurses. BACKGROUND Psychological capital is described as a positive mental state associated with nurses' mental health, quality of care and patient outcomes. METHODS A search was carried out using PubMed, Web of Science, EMBASE, CINAHL, PsycINFO, Cochrane Library and Chinese Database, including China National Knowledge Infrastructure (CNKI), Chinese Biological Medical (CBM), WanFang and Weipu Database from the inception of the databases until October 2021. Subsequently, two researchers identified and reviewed the literature and assessed the risk of bias. A random-effects model was conducted to achieve pooled estimates of psychological capital scales. RESULTS The pooled mean score of the psychological capital scale was 4.21 (95% CI, 4.07-4.35). For subdimensions such as hope, optimism, self-efficacy and resilience, the score was 4.12 (95% CI, 4.11-4.12), 4.34 (95% CI, 4.34-4.34), 4.50 (95% CI, 4.50-4.51) and 4.34 (95% CI, 4.33-4.34), respectively. Subgroup analyses indicated that nurses practising in Asia and intensive care units might have experienced lower psychological capital levels. In addition, significant differences were noted in studies with sample size and publication year. Studies with a large sample size reported a higher psychological capital than those with a small sample size. The pooled mean scores of psychological capital were higher in 2014-2018 than in 2019-2021. Meta-regression further revealed that geographic regions of participants might be a source of heterogeneity, and the Asian region had 32.23% of the heterogeneity between studies, and the African region had 18.71%. CONCLUSION This review is the first to synthesize published research and calculate a pooled score of psychological capital in nurses. These findings indicated that nurses reported a medium-high level of psychological capital, and there was significant heterogeneity. IMPLICATIONS FOR NURSING POLICY Administrators and policymakers should concentrate on nurses' psychological capital and tactically integrate psychological capital into nursing vocational training programs.