Ciara’s study is the first to test whether 2 wearable devices measure sedentary behaviour and physical activity levels accurately in people with Rheumatoid Arthritis, then uses both of these devices to investigate the health consequences associated with engagement in these behaviours, in this population (e.g., functional disability, psychological well being). This study is also the first to investigate Rheumatoid Arthritis patients’ motivation for engaging in sedentary behaviour – by doing so, ways to help people with Rheumatoid Arthritis to reduce their sedentary behaviour can be identified which, in turn, may improve health.