Outcomes assessed in trials of gout and accordance with OMERACT-proposed domains: a systematic literature review

Objective. The aim of this study was to systematically review outcome domains and measurement tools used in gout trials and their accordance with the preliminary OMERACT gout recommendations published in 2005. Methods. Randomized controlled trials (RCTs) and quasi-RCTs investigating any intervention for gout published up to February 2013 were included. Recruitment start dates and all measured outcomes were extracted. Risk of bias (RoB) was assessed with the Cochrane Collaboration tool. Numbers of OMERACT domains were compared for trials at low vs unclear/high RoB and for recruitment start date before 2005 or 2005 and later. Results. Of 9784 articles screened, 38 acute and 30 chronic gout trials were included. Mean (s.d.) number of OMERACT outcomes was 2.9 (1.1) (out of 5) and 2.5 (1.2) (out of 9) for acute and chronic gout trials, respectively. Health-related quality of life, participation and joint damage imaging were not assessed in any trial. Tools used to measure individual domains varied widely. There were no differences in the number of OMERACT outcomes reported in acute or chronic gout trials recruiting before 2005 vs 2005 or later [mean (s.d.): 3.0 (1.1) vs 3.5 (1.3), P = 0.859 and 2.7 (1.1) vs 2.8 (1.4), P = 0.960, respectively]. While both acute and chronic trials at low RoB reported more OMERACT domains than trials at unclear/high RoB, these differences were not significant. Industry-funded trials and trials performed by OMERACT investigators reported more OMERACT outcome domains. Conclusion. We found no appreciable impact of the OMERACT recommendations for gout trials to date.