Comparison of the time-to-indexing in PubMed between biomedical journals according to impact factor, discipline, and...

Practicing evidence-based medicine requires health care professionals to efficiently retrieve relevant and current literature.

The purpose of this study was to compare the time interval between PubMed entry and indexing with Medical Subject Headings (MeSH) between biomedical journals with varying impact factors, focus areas, and health care discipline representation.

This was a cross-sectional study of articles entered into PubMed database between January 1 and December 31, 2012. The primary endpoint was the number of days between PubMed entry and indexing with MeSH terms.

A total of 7906 articles were reviewed across 18 journals. In the first comparison, the time-to-indexing was 177 ± 100 days, 111 ± 69 days, and 23 ± 40 days for articles published in journals with impact factors of 2.0-2.5, 4.5-6.5, and >25, respectively (P ≤ 0.001). In the second comparison, the time-to-indexing was 111 ± 69 days for general medicine versus 170 ± 74 days for specialty journals (P ≤ 0.001). In the third comparison, the overall time-to-indexing was 177 ± 100 days, 234 ± 107 days, and 163 ± 58 days for medicine, nursing, and pharmacy journals, respectively (P ≤ 0.001).

Study results identified a significant delay between entry of articles into the PubMed database and time-to-indexing with MeSH terms across journals of varying impact factor, discipline, and focus. Results suggest that there may be factors that influence the priority by which articles are indexed with MeSH terms. Future research should focus on determining those journal characteristics and any impact of this delay on clinical practice.