Outcome Measures in Evaluation of Weighted Blankets: A Scoping Review

Introduction: Weighted blankets are an intervention used in healthcare settings for alleviating anxiety and sleep problems. Selection of appropriate outcome measures that capture relevant effects is important in clinical practice and research. However, outcomes used are diverse and not standardised. Therefore, this scoping review is aimed at identifying, synthesising, and describing available research and used outcome measures in research studies evaluating weighted blankets. Methods: A scoping review was conducted, with a search of four databases. The search included studies published until February 2024. Results were categorized according to target population (adult or child) and primary outcome (sleep or anxiety). A conceptual map was developed to describe outcome measures used in the field. Results: A total of 38 studies were identified, including 12 randomised controlled trials, 13 pre-post-studies, 6 case studies, 3 register studies, and 3 qualitative studies. The State-Trait Anxiety Inventory and the Anxiety Visual Analogue Scale were commonly used outcome measurements in evaluation of weighted blanket effects on anxiety and most commonly conducted in an adult population. There was considerable heterogeneity in the outcomes used, particularly within the domain of sleep. In studies evaluating weighted blankets as a sleep intervention for children, objective measurement methods such as actigraphy were common, as was the use of a sleep diary. Conclusion: Even though there is extensive research available evaluating weighted blanket use and effects, there is a lack of standardised outcome measures and instruments are not adapted to use within occupational therapy practice. More research is necessary, informing clinical practice about which measures to use and when. Furthermore, there is a need to develop an instrument specifically tailored for use within occupational therapy practice to evaluate sleep interventions.