Literature Search Strategy
A limited literature search was conducted on key resources including PubMed, The Cochrane Library (2014, Issue 1), University of York Centre for Reviews and Dissemination (CRD) databases, Canadian and major international health technology agencies, as well as a focused Internet search. Methodological filters were applied to limit retrieval to health technology assessments, systematic reviews, meta-analyses, randomized controlled trials, and economic studies. Where possible, retrieval was limited to the human population. The search was also limited to English language documents published between January 1, 2009 and February 14, 2014.
Selection Criteria and Methods
One reviewer screened the titles and abstracts of the retrieved publications for relevancy, and evaluated the relevant full-text publications for the final article selection based on the criteria listed in .
Exclusion Criteria
Studies were excluded if they did not meet the selection criteria, if they were duplicate publications or included in a selected systematic review or meta-analysis, or were published prior to January 1, 2009.
Critical Appraisal of Individual Studies
Systematic reviews were critically appraised using the AMSTAR instrument.6 Randomized controlled trials were appraised using the Downs and Black checklist7 and economic analyses were appraised using Drummond’s Checklist.8 Numeric scores were not calculated, and instead, important methodological aspects of each study relating to validity of the study results were summarized.