There is increasing emphasis on reducing the use and improving the safety of mechanical restraint (MR) in psychiatric settings, and on improving the quality of evidence for outcomes. To date, however, a systematic appraisal of evidence has been lacking.

We included studies of adults (aged 18–65) admitted to inpatient psychiatric settings. We included primary randomised or observational studies from 1990 onwards that reported patterns of MR and/or outcomes associated with MR, and qualitative studies referring to an index admission or MR episode. We presented prevalence data only for studies from 2010 onwards. The risk of bias was assessed using an adapted checklist for randomised/observational studies and the Newcastle-Ottawa scale for interventional studies.

We included 83 articles on 73 studies from 1990–2022, from 22 countries. Twenty-six studies, from 11 countries, 2010 onwards, presented data from on proportions of patients/admissions affected by MR. There was wide variation in prevalence (<1–51%). This appeared to be mostly due to variations in standard protocols between countries and regions, which dictated use compared to other restrictive practices such as seclusion. Indications for MR were typically broad (violence/aggression, danger to self or property). The most consistently associated factors were the early phase of admission, male sex, and younger age. Ward and staff factors were inconsistently examined. There was limited reporting of patient experience or positive effects.

MR remains widely practiced in psychiatric settings internationally, with considerable variation in rates, but few high-quality studies of outcomes. There was a notable lack of studies investigating different types of restraint, indications, clinical factors associated with use, the impact of ethnicity and language, and evidence for outcomes. Studies examining these factors are crucial areas for future research. In limiting the use of MR, some ward-level interventions show promise, however, wider contextual factors are often overlooked.

Coercive measures to manage disruptive or violent behaviour are accepted as standard practice in mental healthcare, but systematic knowledge of potentially harmful outcomes is insufficient.

To examine the association of mechanical restraint with several predefined somatic harmful outcomes.

We conducted a population-based, observational cohort study linking data from the Danish national registers from 2007 to 2019. The primary analyses investigated the association of mechanical restraint with somatic adverse events, using panel regression analyses (within-individual analysis) to account for repeated exposures and outcomes. Secondary between-group analyses were performed with a control group exposed to types of coercion other than mechanical restraint.

The study population comprised 13 022 individuals. We report a statistically significant association of mechanical restraint with thromboembolic events (relative risk 4.377, number needed to harm (NNH) 8231), pneumonia (relative risk 5.470, NNH 3945), injuries (relative risk 2.286, NNH 3240) and all-cause death (relative risk 5.540, NNH 4043) within 30 days after mechanical restraint. Estimates from the between-group analyses (comparing the exposed group with a control group of 22 643 individuals) were non-significant or indicated increased baseline risk in the control group. A positive dose–response analysis for cardiac arrest, injury and death supported a causative role of mechanical restraint in the reported associations.

Although the observed absolute risk increases were small, the derived relative risks were non-negligible considering that less restrictive interventions are available. Clinicians and decision makers should be aware of the excess risk in future decisions on the use of mechanical restraint versus alternative interventions.

In the continuous work to reduce the use of coercion in the psychiatric care, attention in Denmark has especially been directed towards mechanical restraint, i.e. the use of belts to fixate patients to a bed. While the use of mechanical restraint is currently decreasing, increases in other types of coercive acts are observed (e.g., forced medication and hourly episodes of manual restraint). The use of manual restraint refers to mental health workers immobilizing a patient to avoid harm to self or others. Manual restraint is generally considered less intrusive to a patient’s autonomy than the use of mechanical restraint. However, no study has yet explored if it is actually experienced as such by the patients.

This study explores patients’ perspectives on manual and mechanical restraint, respectively.

We are currently performing a qualitative interview study of 10 patients, who have been exposed to both types of coercion. The interviews will be transcribed verbatim and analysed for thematic content.

We expect to discover more nuanced perspectives of the intrusiveness of the different forms of coercion—perspectives that may challenge the assumption that one type of coercion is by default better than another. The study’s results will be presented.

In this study, we only look at two types of coercion. More investigation into the differentiation of patients and ideal type of coercive measure is paramount to the ambitions of a better and more humanistic psychiatric care.