A systematic review of head-up tilt to improve consciousness in people with a prolonged disorder of consciousness.

"Declaration of conflicting interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Health Education England (HEE) and the National Institute of Health Research (NIHR) funded this research via providing scholarship money for a Masters in Clinical Research completed by Ms. Harriet Ng. HEE and the NIHR did not take any part creating or analysing this systematic review."

"Funding: The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by HEE, the NIHR and Coventry University. This support was provided through completion of Masters in Clinical Research by Ms. Harriet Ng."

"Two investigators independently performed the search (last search completed 21/6/20). The search and reporting followed the PRISMA statement for systematic reviews. Funding to undertake this systematic review was provided by Health Education England and the National Institute of Health Research. This systematic review was registered in PROSPERO (registration number: CRD42018084069)."