Abstract
The aim of this study was to reassess and compare the usefulness of the National Library of Medicine (NLM)'s Medical Subject Headings® (MeSH) thesaurus for electronic indexing and retrieval of chronobiologic bibliography, after 4 years from a previous study on the same subject (Portaluppi F. Citation2007. Consistency and accuracy of the medical subject headings thesaurus for electronic indexing and retrieval of chronobiologic references. Chronobiol Int. 24:1213–1229) which demonstrated inconsistent and inaccurate results obtained with existing chronobiologic MeSH terms and suggested the inclusion in the MeSH thesaurus of some common chronobiologic concepts and definitions. A sample set of 219 recent chronobiologic references was downloaded from the MEDLINE®'s database together with all MeSH entries associated with them. The following descriptors of obvious chronobiologic relevance were reanalyzed: “chronobiology”, “chronobiology disorders”, “biological clocks”, “circadian rhythm”, “chronotherapy”, “periodicity”, “seasons”, “sleep disorders, circadian rhythm” and “time factors”. Results were comparable with the previous study that we did 4 years ago. The MeSH terms of obvious chronobiologic significance are still inconsistently and inaccurately retrieving chronobiologic references, while none of the common chronobiologic concepts that we suggested have been included in the MeSH thesaurus, which remains largely incomplete for chronobiologic use.