Table 1.
Table summarising the electronic information sources used and the number of records identified
| Type of electronic search | Database | Date range | Number of items (n) |
|---|---|---|---|
| Academic databases | Excerpta Medica dataBASE (EMBASE) via OvidSP | 1974 to 18th March 2020 | 1463 |
| Medical Literature Analysis and Retrieval System Online (MEDLINE) via OvidSP | 1974 to 18th March 2020 | 1144 | |
| PubMed National Centre for Biotechnology Information | 1946 to 18th March 2020 | 1223 | |
| Cumulative Index of Nursing and Allied Health Literature (CINAHL) via EBSCO | 1982 to 18th March 2020 | 384 | |
| Searched on | |||
| Clinical trial registers and/or other sources | ClinicalTrials.gov (www.clinicaltrials.gov) | 18th March 2020 | 193 |
| International Standard Randomised Controlled Trials Number (ISRCTN) Registry (www.isrctn.com) | 18th March 2020 | 48 | |
| Cochrane Central Register of Controlled Trials (CENTRAL) | 18th March 2020 | 962 | |
| World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp) | 18th March 2020 | 270 | |
| NIHR UK Clinical Trials Gateway (www.ukctg.nihr.ac.uk) | 18th March 2020 | 67 |