Examining and Addressing Methodological Gaps To Enhance the Trustworthiness and Relevance of Systematic Reviews and Clinical Practice Guidelines

Abstract

Systematic reviews (SRs) and clinical practice guidelines play a central role in healthcare decision making by synthesising and interpreting evidence to provide actionable recommendations. Their usefulness depends not only on methodological rigor, but also on whether the evidence they summarise reflects outcomes that matter to patients. When methodological decisions prioritise convenience over relevance, or when patient-important outcomes (PIOs) are inconsistently measured or poorly characterised, the resulting evidence may fail to support patient-centred decisions and contribute to avoidable research waste. This thesis applies a methodological lens to key stages of the evidence-to-decision pathway to examine how methodological choices shape the trustworthiness, relevance, and patient-centredness of health evidence. It focuses on decisions made during evidence synthesis and guideline development. Specifically, it evaluates how including conference abstracts can influence SR conclusions, how SRs report and synthesise outcomes that matter to patients, and how patient-reported outcomes (PROs) can be better integrated into the process of moving from evidence to recommendations. Using both empirical and conceptual approaches, this work offers three methodological contributions. First, it shows that the impact of including conference abstracts is context dependent and constrained by reporting limitations. Second, it shown that PIOs are underrepresented in SRs of rehabilitation. Third, it provides guidance to improve the integration of PROs into guideline development. Collectively, these findings identify practical opportunities to strengthen methodological rigor and enhance patient-centred healthcare decisions.