Search Strategies for EMBASE in Ovid Syntax

To develop search filters in EMBASE, we assembled a list of search terms and phrases in a subset of EMBASE records matched with a hand search of the contents of 55 of the 135 journal titles indexed in the year 2000. Search strategies were developed using a 55-journal subset chosen based on those journals that had the highest number of methodologically sound studies; that is, studies that clinicians should be using when making patient care decisions. This selection enriches the sample of target articles, improving the precision of estimates of search term performance and simplifying data processing, but is unlikely to bias the estimates of the sensitivity and specificity of search terms. Search strategies were treated as “diagnostic tests” for sound studies and the manual review of the literature was treated as the “gold standard”. 27,769 articles were included in the analysis and 4,843 unique single-terms were tested.

For each purpose category, the following data are shown: Maximized sensitivity, Maximized specificity, Best balance of sensitivity and specificity . In the second column of the table the search strategies are shown in Ovid syntax. In the third column of the table: sens = sensitivity; spec = specificity; prec = precision; acc = accuracy. References for the methods and individual categories appear at the end of the document.

To view the search filters for MEDLINE and PsycINFO, please click on the appropriate link. To find out more about the Hedges Project, click here.


Therapy - EMBASE

Filter type

Ovid Filter

Sens / spec / prec / acc (%)
Maximizes sensitivity

random:.tw.
OR clinical trial:.mp.
OR exp health care quality

99 / 72 / 14 / 73

Maximizes specificity

double-blind:.mp.
OR placebo:.tw.
OR blind:.tw.
52 / 97 / 43 / 95
Best balance of sensitivity and specificity

random:.tw.
OR placebo:.mp.
OR double-blind:.tw.

95 / 93 / 38 / 93

Diagnosis - EMBASE

Filter type

Ovid Filter

Sens / spec / prec / acc (%)
Maximizes sensitivity

di.fs.
OR predict:.tw.
OR specificity.tw.

100 / 70 / 1 / 71

Maximizes specificity

specificity.tw.
63 / 98 / 11 / 98
Best balance of sensitivity and specificity

sensitiv:.tw.
OR diagnostic accuracy.sh.
OR diagnostic.tw.

90 / 92 / 3 / 92

Prognosis - EMBASE

Filter type

Ovid Filter

Sens / spec / prec / acc (%)
Maximizes sensitivity

exp disease course
OR risk:.mp.
OR diagnos:.mp.
OR follow-up.mp.
OR ep.fs.
OR outcome.tw.

99 / 51 / 1 / 51
Maximizes specificty

prognos:.tw.
OR survival.tw.

51 / 93 / 4 / 93
Best balance of sensitivity and specificity

follow-up.mp.
OR prognos:.tw.
OR ep.fs.

80 / 80 / 2 / 80

Reviews - EMBASE

Filter type

Ovid Filter

Sens / spec / prec / acc (%)
Maximizes sensitivity

exp methodology
OR search:.tw.
OR review.pt.

95 / 64 / 2 / 64
Maximizes specificity

meta-analysis.tw.
OR systematic review.tw.

61 / 99 / 41 / 99
Best balance of sensitivity and specificity

meta-analys:.mp.
OR search:.tw.
OR review.pt.

92 / 88 / 6 / 88

Clinical Prediction Guides - EMBASE

Filter type

Ovid Filter

Sens / spec / prec / acc (%)
Maximizes sensitivity

predict:.tw.
OR exp methodology
OR validat:.tw.

97 / 74 / 1 / 74
Maximizes specificity

validation.tw.
OR prediction.tw.

61 / 99 / 11 / 99
Best balance of sensitivity and specificity

validat:.mp.
OR index.tw.
OR model.tw.

91 / 90 / 2 / 90

Qualitative - EMBASE

Filter type

Ovid Filter

Sens / spec / prec / acc (%)
Maximizes sensitivity

interview:.tw.
OR qualitative.tw.
OR exp health care organization

94 / 90 / 3 / 90
Maximizes specificity

qualitative.tw.
OR qualitative study.tw.

57 / 100 / 34 / 100
Best balance of sensitivity and specificity

interview:.tw.
OR exp health care organization
OR experiences.tw.

90 / 90 / 3 / 90

Causation (Etiology) - EMBASE

Filter type

Ovid Filter

Sens / spec / prec / acc (%)
Maximizes sensitivity

risk:.mp.
OR exp methodology
OR exp epidemiology

92 / 61 / 2 / 61
Maximizes specificity

cohort.tw.
OR relative risk:.tw.

53 / 95 / 7 / 9
Best balance of sensitivity and specificity

risk.tw.
OR mortalit:.tw.
OR cohort.tw.

82 / 81 / 3 / 81

Economics - EMBASE

Filter type

Ovid Filter

Sens / spec / prec / acc (%)
Maximizes sensitivity

cost effectiveness analysis.sh.
OR randomized.tw.
OR economic.tw.

100 / 92 / 1 / 92
Maximizes specificity

cost effectiveness.tw.
OR sensitivity analys:.tw.

52 / 99 / 9 / 99
Best balance of sensitivity and specificity

cost.tw.
OR costs.tw.

97 / 98 / 4 / 98

References

Wilczynski NL, Haynes RB, for the Hedges Team. EMBASE search strategies achieved high sensitivity and specificity for retrieving methodologically sound systematic reviews. J Clin Epidemiol. 2007 Jan;60(1):29-33.

McKinlay RJ, Wilczynski NL, Haynes RB, and the Hedges Team. Optimal search strategies for detecting cost and economic studies in EMBASE.BMC Health Services Research. 2006 Jun;6:67. Free full text linkhttp://www.biomedcentral.com/1472-6963/6/67

Wong SSL, Wilczynski NL, Haynes RB. Developing optimal search strategies for detecting clinically sound treatment studies in EMBASE.  J Med Libr Assoc. 2006 Jan;94(1)41-7. Free full text link: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1324770/?tool=pubmed

Walters LA, Wilczynski NL, Haynes RB, for the Hedges Team. Developing optimal search strategies for retrieving clinicallly relevant qualitative studies in EMBASE. Qual Health Res. 2006 Jan;16(1):162-8.

Wilczynski NL, Haynes RB; Hedges Team. EMBASE search strategies for identifying methodologically sound diagnostic studies for use by clinicians and researchers. BMC Med. 2005 Mar 29;3(1):7. Free full text link: http://www.biomedcentral.com/content/pdf/1741-7015-3-7.pdf

Wilczynski NL, Haynes RB, for the Hedges Team. strong>Optimal search strategies for detecting clinically sound prognostic studies in EMBASE: an analytic survey. J Am Med Inform Assoc. 2005 Jul-Aug;12(4):481-5. Free full text link: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1174893/?tool=pubmed

Haynes RB, Kastner M, Wilczynski NL; Hedges Team. Developing optimal search strategies for detecting clinically sound and relevant causation studies in EMBASE. BMC Med Inform Decis Mak. 2005 Mar 22;5(1):8. Free full text link: http://www.biomedcentral.com/content/pdf/1472-6947-5-8.pdf

Holland JL, Wilczynski NL, Haynes RB; Hedges Team. Optimal search strategies for identifying sound clinical prediction studies in EMBASE. BMC Med Inform Decis Mak. 2005 Apr 29;5(1):11. Free full text link: a href=”http://www.biomedcentral.com/1472-6947/5/11″ target=”_blank” rel=”noopener”>http://www.biomedcentral.com/1472-6947/5/11