Objectives: To determine the percentage of dental-related randomized controlled trials (RCTs) that are indexed in MEDLINE, and of those that are indexed, what proportion are classified correctly as an RCT Publication Type.
Methods: Assuming that RCTs identified in Cochrane Reviews are classified correctly as RCTs, we identified 361 RCTs from 39 Cochrane Reviews listed under the Oral Health topic. We then completed PubMed searches and determined how many of these articles were indexed and how many were classified as RCTs in MEDLINE.
Results: Of the 361 RCTs, 95.8% (95% CI: 93.7 to 97.9) were indexed in MEDLINE and 87.0% (95% CI: 83.5 to 90.5) of these were correctly classified as an RCT Publication Type. Reasons why articles were not indexed included: article in press, journal not included in MEDLINE.
Conclusion: Approximately 17% of RCTs may not be identified when searching for RCTs using PubMed. Approximately 4% are not indexed at all, and approximately 13% of the articles identified as RCTs in oral health systematic reviews are not classified as RCTs in MEDLINE.
Supported by NIH/1R25DE018663