Selecting and measuring optimal outcomes for randomised controlled trials in surgery

Randomised controlled trials (RCTs) in surgery are complex to design and conduct and face unique challenges compared to trials in other specialties. The appropriate selection, measurement and reporting of outcomes are one aspect that requires attention. Outcomes in surgical RCTs are often ill-defined, inconsistent and at high risk of bias in their assessment and historically, there has been an undue focus on short-term outcomes and adverse events meaning the value of trial results for clinical practice and decision-making is limited. This review addresses three key problems with surgical trial outcomes-choosing the right outcomes for the trial design and purpose, selecting relevant outcomes to measure from the range of possible outcomes, and measuring outcomes with minimal risk of bias. Each obstacle is discussed in turn, highlighting some suggested solutions and current initiatives working towards improvements in these areas. Some examples of good practice in this field are also discussed. Many of the historical problems with surgical trial outcomes may be overcome with an increased understanding of the trial design and purpose and recognition that pragmatic trials require assessments of outcomes that are patient-centred in addition to measurement of short-term outcomes. The use of core outcome sets developed for specific surgical interventions and the application of novel methods to blind outcome assessors will also improve outcome measurement and reporting. It is recommended that surgeons work together with trial methodologists to integrate these approaches into RCTs in surgery. This will facilitate the appropriate evaluation of surgical interventions with informative outcomes so that results from trials can be useful for clinical practice.