What mechanisms could link GP relational continuity to patient outcomes?

BACKGROUND

Relational continuity of GP care, defined as a patient seeing the same doctor repeatedly, is a means towards the end of better reciprocal doctor–patient relationships. It has been linked to various outcomes for patients, doctors, and health systems, including patient satisfaction, reduced accident and emergency use, better concordance with medical advice, and reduced hospital admissions.¹ Two systematic reviews^2,3 have found that continuity is associated with reduced mortality; one in primary care.³ Another aggregate outcome of continuity is reduced costs in the health system, important when countries face cost pressures in health care. In antenatal care, there is evidence from 15 randomised trials that continuity improves outcomes,⁴ but in general practice trials have not yet been completed.

Hundreds of studies from various countries and health systems have linked increased continuity to positive outcomes; some show no link and only a few an association with adverse effects.¹ To the best of our current knowledge, and on the balance of probabilities, continuity is likely to be beneficial. On this basis it is now important to consider what possible mechanisms can explain the continuity effects.

Outcome-specific mechanisms for continuity of care have been proposed separately and several were brought together in our previous reviews.^1,5 The concept of accumulated knowledge was first proposed by Hjortdahl in 1992.⁶ Parchman and Burge wrote: ‘length of relationship and communication predicted accumulated knowledge of the patient by the physician, accumulated knowledge predicted trust, and trust predicted delivery of preventive services’.⁷ The GP taking greater responsibility has been suggested as a potential mechanism for a mortality reduction. The reports from recent studies into outcomes linked to continuity of care commonly suggest knowledge, trust, and adherence to treatments as likely mechanisms. Other mechanisms include saving time, improved communication, …