Uptake of methodological advances for synthesis of continuous and time-to-event outcomes would maximise use of the evidence base.

OBJECTIVE:To establish how often continuous and time-to-event outcomes are synthesised in health technology assessment (HTA), the statistical methods and software used in their analysis and how often evidence synthesis informs decision models. STUDY DESIGN AND SETTING:Review of NIHR HTA reports, NICE technology appraisals and NICE guidelines reporting quantitative meta-analysis or network meta-analysis of at least one continuous or time-to-event outcome published 01/04/2018 - 31/03/2019. RESULTS:We identified 47 eligible articles. At least one continuous or time-to-event outcome was synthesised in 51% and 55% of articles respectively. Evidence synthesis results informed decision models in two-thirds of articles. The review and expert knowledge identified five areas where methodology is available for improving the synthesis of continuous and time-to-event outcomes: i) outcomes reported on multiple scales, ii) reporting of multiple related outcomes, iii) appropriateness of the additive scale, iv) reporting of multiple time points and v) non-proportional hazards. We identified three anticipated barriers to the uptake and implementation of these methods: i) statistical expertise, ii) software and iii) reporting of trials. CONCLUSION:Continuous and time-to-event outcomes are routinely reported in HTA. However, increased uptake of methodological advances could maximise the evidence base used to inform the decision making process.