Study designs of evaluations included in the review
Randomised controlled trials (RCTs) were eligible for the review.
Specific interventions included in the review
Eligible studies involved a stress- or trauma-based writing task. Interventions that involved both written and oral expression were excluded. The studies were required to include a neutral writing or no-writing control group. The interventions in most of the included studies involved three or four writing sessions of 10 to 30 minutes (typically 20 minutes) on consecutive days or spread over 1 to 3 weeks.
Participants included in the review
There were no inclusion criteria for the participants. The participants in the included studies were healthy people (predominantly students), patients with medical illnesses (fibromyalgia, asthma, irritable bowel syndrome, cancer or cystic fibrosis), or people with a psychological diagnosis or history of exposure to stress. The majority of the participants were women.
Outcomes assessed in the review
The studies were required to report a measure of HCU, for example the number of doctor or clinic visits (not self-reported symptoms, sick days or hospital visits) measured at least 4 weeks after the intervention. The studies were also required to report sufficient information to allow the treatment effect size (standardised mean difference) to be calculated. Most of the included studies assessed HCU from records or self-report, and the duration of follow-up ranged from 4 to 52 weeks.
How were decisions on the relevance of primary studies made?
The author did not state how the papers were selected for the review, or how many reviewers performed the selection.