90% of contacts with formal healthcare services take place in primary care and osteoarthritis is the most common, disabling long-term condition seen in this setting. In this presentation the value of observational cohort studies of osteoarthritis in primary care will be critically examined using illustrative findings from a series of cohort studies undertaken in the past decade - the Clinical Assessment Studies (CAS). Of central concern is the ability to generate practice-relevant evidence consistent with the defining functions of primary care: notably, generalist, person-focussed care; the management of undifferentiated illness at first contact; and the provision of care across the lifecourse, typically at a high volume and low cost. These functions have major implications for early diagnosis and prognosis and for understanding osteoarthritis in the context of multimorbidity. The presentation concludes by looking at the prospects for routine primary care data to support meaningful observational cohort research.

Disclosure of Interest None Declared