Searching the Literatura Latino Americana e do Caribe em Ciências da Saúde (LILACS) database improves systematic reviews.

Background: An unbiased systematic review (SR) should analyse as many articles as possible in order to provide the best evidence available. However, many SR use only databases with high English-language content as sources for articles. Literatura Latino Americana e do Caribe em Ciências da Saúde (LILACS) indexes 670 journals from the Latin American and Caribbean health literature but is seldom used in these SR. Our objective is to evaluate if LILACS should be used as a routine source of articles for SR.

Methods: First we identified SR published in 1997 in five medical journals with a high impact factor. Then we searched LILACS for articles that could match the inclusion criteria of these SR. We also checked if the authors had already identified these articles located in LILACS.

Results: In all, 64 SR were identified. Two had already searched LILACS and were excluded. In 39 of 62 (63%) SR a LILACS search identified articles that matched the inclusion criteria. In 5 (8%) our search was inconclusive and in 18 (29%) no articles were found in LILACS. Therefore, in 71% (44/72) of cases, a LILACS search could have been useful to the authors. This proportion remains the same if we consider only the 37 SR that performed a meta-analysis. In only one case had the article identified in LILACS already been located elsewhere by the authors' strategy.

Conclusion: LILACS is an under-explored and unique source of articles whose use can improve the quality of systematic reviews. This database should be used as a routine source to identify studies for systematic reviews.