Rehabilitation and COVID-19: systematic review by Cochrane Rehabilitation.

Every one of the 53 trials was rated at high risk of bias overall; 44 (83%) were at high risk on blinding of participants and staff. The trials could not be pooled, so there is no combined estimate of effect for any intervention. Certainty of evidence was low or very low for every outcome, largely because many comparisons had fewer than 400 or 200 participants. Severity of COVID-19 was often not defined in the trials, and populations mixed different disease stages and levels of disability, so it is hard to know who a result applies to. The search stopped at the end of 2022, and studies not published in English and grey literature were excluded. Twenty-seven trials (51%) had not registered a protocol, so reporting bias could not be checked. Four trials reported no outcome of interest at all, and many others did not report adverse events.

The authors declare no conflict of interest with any financial organisation regarding the material discussed. The work was funded by the Italian Ministry of Health (Ricerca Corrente). The funders had no role in study design, data collection and analysis, the decision to publish, or preparing the manuscript.

Do not read the individual positive results as proof that breathing exercises, strengthening or telerehabilitation work after COVID. The reviewers rated every outcome low or very low certainty and every one of the 53 trials at high risk of bias, and they could not pool the data, so no single intervention can be called effective on this evidence.