Non-randomized Studies: Filters
Inclusion of a search filter on this site is not an endorsement of its validity or a recommendation for its use by the editors of this site, by the InterTASC Information Specialists SubGroup or by the (UK) National Institute for Health and Care Excellence (NICE). For suggestions on the appraisal of filters see the ISSG Search Filter Appraisal Checklist.
This page shows publications that have reviewed search filter performance and individual search filters.
Please note that other filter sites/filter collections may have relevant filters for this topic.
Publications that review search filter performance
Hausner E, Metzendorf MI, Richter B, Lotz F, Waffenschmidt S. Study filters for non-randomized studies of interventions consistently lacked sensitivity upon external validation. BMC Med Res Methodol. 2018 Dec 18;18(1):171. doi: 10.1186/s12874-018-0625-4.
Individual search filters
Database indexing changes over time and new vocabulary may be introduced. With older filters, please check the subject indexing to ensure that the subject indexing is still current and, if not, consider whether new vocabulary may need to be added to the filter. Please note that if filters are amended, the performance may change from that published in the original articles and the filter should be reported as amended from the original filter.
Embase
Furlan AD, Irvin E, Bombardier C. Limited search strategies were effective in finding relevant nonrandomized studies. J Clin Epidemiol. 2006;59(12):1303-11. [Ovid]
MEDLINE
Waffenschmidt S, Navarro-Ruan T, Hobson N, Hausner E, Sauerland S, Haynes RB. Development and validation of study filters for identifying controlled non-randomized studies in PubMed and Ovid MEDLINE. Res Synth Methods. 2020; 11(5): 617-626. doi:10.1002/jrsm.1425
The filters are validated in research presented at the EAHIL 2022 Conference by Irma Klerings, Anna Glechner and Martin Fangmeyer. The impact of using search filters for non-randomised studies on rapid reviews.
University of Texas School of Public Health. Search filters for case-control studies. Updated 14 June 2013. [Ovid]
Fraser C, Thomson-O'Brien MA. Identifying non-randomised studies in Medline. 8th International Congress on Medical Librarianship; 2000 July 2-5; London, UK.
Fraser C, Thomson MA. Identifying non-randomised studies in Medline. In: Systematic reviews: evidence for action. Poster presented at the 6th Cochrane Colloquium; 1998 22-26 Oct; Baltimore, USA. 1998.
Furlan AD, Irvin E, Bombardier C. Limited search strategies were effective in finding relevant nonrandomized studies. J Clin Epidemiol. 2006;59(12):1303-11. [Ovid]
Royle P, Waugh N. Literature searching for clinical and cost-effectiveness studies used in health technology assessment reports carried out for the National Institute for Clinical Excellence appraisal system. Health Technol Assess. 2003;7(34): iii, ix-x, 1-51. DOI: https://doi.org/10.3310/hta7340 PMID: 14609481. [Ovid]
PsycInfo
University of Texas School of Public Health. Search filters for case-control studies and clinical trials. Accessed 06 Dec 2013.[Ovid]
Launch search filter for case control studies in Ovid APA PsycINFO (subscribers only)