Evidence Base Methodology

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Evidence Base Methodology

The objective of the evidence base is to disseminate the best available information to promote the quality of HBV and HCV prevention services and achieve elimination goals. By reviewing all of the systematic reviews and guidelines on a particular topic, the evidence base provides readers with information on the generalizability of specific initiatives and the quality of the underlying evidence.

The evidence base is developed on the foundation of high-quality systematic review methods. A medical librarian develops and conducts literature searches in the peer-reviewed and grey literature. Peer-reviewed databases include Ovid MEDLINE; Embase; Wiley Cochrane Database of Systematic Reviews; and EBSCO CINAHL. Grey literature (literature that is not commercially published) was identified by searching the websites of relevant organizations, as well as clinical guideline repositories and a health technology assessment agency database. Google was used to search for additional Web-based materials.

Two investigators independently and in duplicate reviewed titles and abstracts of identified references. Investigators screened full-text studies that met inclusion criteria. Investigators extracted information from studies eligible at the full-text stage pertaining to characteristics specific to either systematic reviews or guidelines on pertinent information iteratively developed between investigators and content experts. Screening and extraction were performed using DistillerSR (Evidence Partners, Ottawa, Canada).

Quality assessment of eligible systematic reviews and guidelines were conducted independently and in duplicate using validated instruments appropriate to the study design. For systematic reviews, investigators applied A MeaSurement Tool to Assess systematic Reviews (AMSTAR) 2 to evaluate the methodological quality of systematic reviews of randomized and non-randomized studies (1). For guidelines, investigators used the Appraisal of Guidelines for Research & Evaluation Instrument (AGREE II) to evaluate the quality and reporting of practice guidelines (2). Readers should understand the assessment criteria in the instruments to inform the overall quality rating and their appropriateness to evaluate some study designs. If multiple iterations of guideline documents have been published, the evidence base provides a quality assessment of the most recent (i.e. current) guideline.

The evidence base currently presented characteristics of interventions identified in systematic reviews and guideline documents to inform implementation of timely hepatitis B birth dose. For the hepatitis B birth dose topic, a medical librarian developed and conducted searches in the peer-reviewed and grey literature from database inception (no limit on date of earliest publications) through December 31, 2018. Published literature was identified by searching the following bibliographic databases: Ovid MEDLINE: Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Ovid MEDLINE Daily and Ovid MEDLINE 1946-Present, Embase Classic+Embase 1947 to 2019 January 11; Wiley Cochrane Database of Systematic Reviews; and EBSCO CINAHL. The evidence base presents 14 systematic reviews (including economic evaluations based on systematic reviews and narrative reviews) and 26 guidelines published in English.

Updates to the evidence base are planned to address subsequent research priorities.