Search strategy databases
| Cumulative Index to Nursing and Allied Health Literature (CINAHL) | 1982–current |
| Cochrane Database of Systematic Reviews (CDSR) | 1996–current |
| Cochrane Central Register of Controlled Trials (CENTRAL) | 1996–current |
| Cochrane Methodology Register (CMR) | 1980–current |
| MEDLINE | 1946–current |
| MEDLINE In-Process and Other Non-Indexed Citations | 1951–current |
| PsycINFO | 1806–current |
| Web of Science | 1900–current |
| ERIC | 1964–current |