Outcome measures in rheumatoid arthritis randomised trials over the last 50 years

Abstract

Background: The development and application of standardised sets of outcomes to be measured and reported in clinical trials have the potential to increase the efficiency and value of research. One of the most notable of the current outcome sets began nearly 20 years ago: the World Health Organization and International League of Associations for Rheumatology core set of outcomes for rheumatoid arthritis clinical trials, originating from the OMERACT (Outcome Measures in Rheumatology) Initiative. This study assesses the use of this core outcome set by randomised trials in rheumatology.

Methods: An observational review was carried out of 350 randomised trials for the treatment of rheumatoid arthritis identified through The Cochrane Library (up to and including September 2012 issue). Reports of these trials were evaluated to determine whether or not there were trends in the proportion of trials reporting on the full set of core outcomes over time. Researchers who conducted trials after the publication of the core set were contacted to assess their awareness of it and to collect reasons for non-inclusion of the full core set of outcomes in the study.

Results: Since the introduction of the core set of outcomes for rheumatoid arthritis, the consistency of measurement of the core set of outcomes has improved, although variation in the choice of measurement instrument remains. The majority of trialists who responded said that they would consider using the core outcome set in the design of a new trial.

Conclusions: This observational review suggests that a higher percentage of trialists conducting trials in rheumatoid arthritis are now measuring the rheumatoid arthritis core outcome set. Core outcome sets have the potential to improve the evidence base for health care, but consideration must be given to the methods for disseminating their availability amongst the relevant communities.

Figure 1

Flow diagram of rheumatoid arthritis Cochrane systematic reviews included in study. DMARD, disease-modifying anti-rheumatic drugs; SAARD, slow-acting anti-rheumatic drugs; SMARD, symptom-modifying anti-rheumatic drugs.

Figure 2

Evaluation of randomised controlled trials within reviews. * One duplicate trial assessed under SMARD only. ** Two duplicate trials assessed under SMARD only. SMARD, disease-modifying anti-rheumatic drugs; SAARD, slow-acting anti-rheumatic drugs; SMARD, symptom-modifying anti-rheumatic drugs.

Figure 3

Percentage of trials reporting on the full rheumatoid arthritis core outcome set and the average number of clinical outcomes measured over time (10-point moving yearly average). Note: The updated European Medicines Agency guideline first came into operation in June 2004 [12], although this was based on an earlier version adopted in 1998. This guideline is currently under further revision as from 2011. The Food and Drug Administration guideline was first released in 1996 but was not formalised until 1999 [11]. There has been no formal revision of this guideline since 1999.