Table 5.
Comparison of Google Scholar and PubMed in systematic review searching
| Google Scholar | PubMed |
|---|---|
| Shows up to 1,000 results |
Shows all results |
| Searches the full text of the article, and words on the webpage |
Searches only bibliographic data and controlled vocabulary (MeSH terms) |
| No controlled vocabulary available |
Controlled vocabulary (MeSH terms) added by skilled indexers and searchable (including 'explode’) |
| Searches the broad aspect of science (filters limiting results to medical articles were removed) |
Only contains articles on medical topics |
| No search history available (unable to compare or combine record sets) |
Detailed search history available, flexibility in combining record sets to create complicated search strategies |
| Search queries limited to 256 characters |
No limits on the length of search queries |
| No truncation allowed. Tilde can be used to search for variants, but cannot be used in OR relationship with other words. GS is said to search for word variants, but this is very rare and the mechanism is unclear. |
Truncation allowed |
| Possibly automatic searching for synonyms (details unclear) |
Automatic Term Mapping (details available) |
| Field names only for title (complete query) and author names |
Field names for many fields can be assigned per synonym |
| No advanced limits (for publication type, human studies and so on) |
Multiple advanced limits in the database itself, or available from third parties |
| Cannot accurately limit to search dates (no controlled updates) |
Different date fields available to limit searches to results before a certain date |
| Cannot download results in bulk to reference management software |
Multiple options to download the complete results set to reference management software |
| Proximity searching only with exact order and exact number of connecting words | No proximity search possible |