A randomised, controlled study of outcome and cost effectiveness for RA patients attending nurse-led rheumatology clinics: Study protocol of an ongoing nationwide multi-centre study

Background: The rise in the number of patients with arthritis coupled with understaffing of medical services has seen the deployment of Clinical Nurse Specialists in running nurse-led clinics alongside the rheumatologist clinics. There are no systematic reviews of nurse-led care effectiveness in rheumatoid arthritis. Few published RCTs exist and they have shown positive results for nurse-led care but they have several limitations and there has been no economic assessment of rheumatology nurse-led care in the UK. Objective: This paper outlines the study protocol and methodology currently being used to evaluate the outcomes and cost effectiveness for patients attending rheumatology nurse-led clinics. Design and methods: A multi-centred, pragmatic randomised controlled trial with a non-inferiority design; the null hypothesis being that of 'inferiority' of nurse-led clinics compared to physician-led clinics. The primary outcome is rheumatoid arthritis disease activity (measured by DAS28 score) and secondary outcomes are quality of life, self-efficacy, disability, psychological well-being, satisfaction, pain, fatigue and stiffness. Cost effectiveness will be measured using the EQ-5D, DAS28 and cost profile for each centre. Power calculations: In this trial, a DAS28 change of 0.6 is considered to be the threshold for clinical distinction of 'inferiority'. A sample size of 180 participants (90 per treatment arm) is needed to reject the null hypothesis of 'inferiority', given 90% power. Primary analysis will focus on 2-sided 95% confidence interval evaluation of between-group differences in DAS28 change scores averaged over 4 equidistant follow up time points (13, 26, 39 and 52 weeks). Cost effectiveness will be evaluated assessing the joint parameterisation of costs and effects. Results: The study started in July 2007 and the results are expected after July 2011. Trial registration: The International Standard Randomised Controlled Trial Number ISRCTN29803766