Table 1: Comparison of results retrieved through the 37 search strategies, either with or without use of variations in the MEDLINE (via PubMed) and EMBASE databases.
| Comparison between with and without variations | Equal numbers of results retrieved (%) | Greater number of results retrieved with variations (%) | Smaller number of results retrieved with variations (%) | P-value | |
|---|---|---|---|---|---|
| MEDLINE via PubMed | MeSH | 27 (73.0)a | 10 (27.0)b | 0 (0.0)c | P < 0.0001 |
| MeSH + EMTREE | 20 (54.0)a | 16 (43.3)a | 1 (2.7)b | P < 0.0001 | |
| EMTREE | 21 (56.8)a | 14 (37.8)a | 2 (5.4)b | P < 0.0001 | |
| EMBASE | MeSH | 12 (32.4)a | 25 (67.6)b | 0 (0.0)c | P < 0.0001 |
| MeSH + EMTREE | 10 (27.0)a | 26 (70.3)b | 1 (2.7)c | P < 0.0001 | |
| EMTREE | 16 (43.3)a | 20 (54.0)a | 1 (2.7)b | P < 0.0001 | |
a, b, c = values followed by the same letter did not differ significantly.