What is a systematic literature review (SLR)?

A systematic literature review (SLR) is a type of study in which a search of the published literature is conducted using a pre-specified and structured approach. They are a good way to get an understanding of what evidence is currently available on a specific question or topic and in turn can be used to inform understanding of key data gaps. They can also be the first step in collating studies that can then be used in meta-analyses.

SLRs are usually structured in terms of the population of interest, interventions of interest, comparators of interest, and outcomes of interest (summarized as the PICO of the study). Specific databases (such as PubMed, EMBASE, etc.) are usually queried to find an initial hit of lists and then combed through to determine whether specific studies meet the PICOs for the systematic literature review. The general aim is to start with a much broader search strategy and then narrow from there in order to ensure all relevant studies are included and nothing of importance is missed.

HEOR and Medical teams may work on SLRs in order to understand the evidence in a given space and to inform other deliverables including regulatory or HTA submissions, meta-analysis, economic modeling, ISR decisionmaking, and need for additional clinical trials.