What do tests do for doctors? A qualitative study of blood testing in UK primary care

Background. Rates of blood testing are rising with significant geographical variability. Most research into diagnostic testing focuses on the role of tests in diagnostic decision-making. Objective. The aim of this study was to explore the non-medical motives for blood testing by considering what tests do for doctors, through qualitative interviews with general practitioners (GPs). Methods. We undertook 23 in-depth semi-structured interviews with UK GPs. Reasons for performing recent inflammatory marker blood tests were explored by reviewing GPs pathology inboxes to ground discussions in real-life clinical practice. Interviews were transcribed verbatim and analysed using a grounded theory approach. Results. Blood tests offer doctors a tool to manage uncertainty; within a context of increased litigation, risk aversion and reduced continuity of care. Tests can also be offered as a 'gift' for patients, a way to be seen to be 'doing something'; in the social context of time pressures and perceived patient pressures. There was a tension however. On the one hand, doctors talked about using tests for reassurance and as a 'gift' offering 'truth'. Yet paradoxically, they also discussed the challenges of uncertainty and anxiety from inconclusive test results. Conclusion. Our study emphasises that defining 'unnecessary' blood testing may not be as simple as determining medical criteria for testing; psychosocial reasons may be equally valid and interlinked. Further research is needed to help GPs manage uncertainty within the context of a risk averse society, and to explore the congruence and dissonance between doctors' and patients' perceptions of testing.