Increasing Psychological Capital: A Pre-Registered Meta-Analysis of Controlled Interventions

The aim of this meta-analysis was to evaluate the overall effectiveness of interventions designed to enhance psychological capital (PsyCap), well-being, and performance. We used inclusion criteria such as: to have an experimental design, the sample to be formed by employees or students, to contain a measure of PsyCap, and a control group. Forty-one trials (N_total = 3,911) met these criteria. The overall effect of the interventions on all PsyCap variables was significant but small (d = 0.34, k = 41, Z = 6.74, p < .001). Separate analyses on each of the PsyCap variables also revealed significant effects: small effects on developing PsyCap (d = 0.26, k = 9, Z = 4.37, p < .001), hope (d = 0.22, k = 5, Z = 2.26, p < .05), self-efficacy (d = 0.37, k = 18, Z = 4.11, p < .001), and optimism (d = 0.36, k = 12, Z = 2.52, p < .05), and a small to medium effect for resilience (d = 0.49, k = 12, Z = 3.61, p < .001). The effectiveness of the PsyCap interventions on well-being and performance is also significant.