Systematic review and meta-analysis of the effectiveness of expressive writing disclosure on cancer and palliative care patients’ health-related outcomes

Objectives: This review aimed to synthesize the available evidence on the effectiveness of expressive writing (EW) on health outcomes of patients with cancer. Methods: A systematic review and meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Six databases were searched from 1986 to 9 July 2022. The searches were updated on 3 October 2023. Methodological quality was assessed using the Cochrane Risk of Bias tool for randomized controlled trials (RCTs) and ROBINS-I tool for non-RCTs Mixed Methods Appraisal Tool. Narrative synthesis of outcomes was performed where meta-analysis was not appropriate. Results: Thirty-four studies with 4316 participants were identified, including 31 RCTs and three non-RCTs. Twenty-one studies focused on women with breast cancer; the remainder recruited people with various cancer types. There was a significant improvement in fatigue (SMD = − 0.3, 95% CI − 0.55 to − 0.66, P =.002), passive mood (MD = − 3.26, 95% CI = − 5.83 to − 0.69, P = 0.001), and the physical dimension of quality of life (MD = 3.21, 95% CI 0.18 to 6.25, P = 0.04) but not for anxiety, depression, and global quality of life among patients who participated in EW when compared with control groups. Conclusion: Findings showed some benefits of EW for people with cancer, but not necessarily in anxiety or depression. Heterogeneity in the delivery of interventions and their content, and shortcomings in the methodologies used highlight the need for stronger evidence in the field through high-quality trials and consistencies in the protocol, focusing on outcomes that this review highlighted as potential outcome targets.