A comprehensive international study – a clinical trial with a qualitative study led by UMC Utrecht and the University of Oxford reports that point-of-care diagnostic testing, when used as a standalone solution, is unlikely to reduce antibiotic prescribing for respiratory infections in primary care. The findings indicate that testing must be embedded within broader antimicrobial stewardship strategies to be effective.
The results of the PRUDENCE trial, published in The Lancet Primary Care, was led by researchers at UMC Utrecht and the University of Oxford, with collaborators in 13 European countries. Part of the randomized controlled trial with 2,639 patients was an in-depth qualitative evaluation involving clinicians and patients in six countries. Together, the studies provide the most comprehensive evaluation to date of whether rapid diagnostic testing can meaningfully decrease antibiotic use in real-world primary care settings.
Around 80 percent of antibiotics are prescribed by GPs in primary care, and most of these prescriptions are for respiratory infections such as sore throats and coughs, which are usually caused by viruses and do not need antibiotics. Point-of-care tests have been widely promoted as a tools to help clinicians in treatment decision making, thereby reducing unnecessary prescriptions.
The clinical trial ran from December 2021 to January 2024 and enrolled 2,639 patients aged one year and older who presented with a cough or sore throat. Participants were included because their clinician was considering to prescribe antibiotics. They were randomly assigned to usual care alone or to usual care plus a point-of-care testing strategy. Testing could include a CRP test (an acute phase protein measured in blood), a group A streptococcus test (a rapid throat swab), an influenza A and B test, or a combination of these tests depending on clinical symptoms, influenza season and SARS-CoV-2 status.
Antibiotics were prescribed to 45.7 percent of patients in the point-of-care testing group and 47.1 percent in the usual care group, a difference that is not statistically significant. Both groups recovered at the same rate, taking an average of four days to return to their usual daily activities. The study also found no increase in complications or serious adverse events linked to the testing strategy. The trial concludes that point-of-care testing, when introduced as a standalone strategy in situations where clinicians are already inclined to prescribe antibiotics, does not substantially reduce antibiotic prescribing.
Dr. Alike van der Velden
First author of the paper Alike van der Velden, PhD (Department of General Practice, UMC Utrecht) said: “Point-of-care tests can have potential, but our study shows that diagnostics on their own do not automatically change prescribing decisions. When clinicians are already leaning towards antibiotics, test results alone don’t sway them towards non-prescribing. To make a meaningful difference, rapid testing must be combined with other interventional elements, like clinician training, evidence that supports that following the implications of the test is safe, and support to manage patient expectations.”
The qualitative study, published in the same issue of The Lancet Primary Care, embedded within the trial explored how clinicians and patients experienced and used point-of-care testing in routine practice. Researchers conducted in-depth interviews with 56 patients and 33 clinicians across six countries. The findings from this study explain why the trial did not lead to a reduction in prescribing rates.
Clinicians often used test results to confirm decisions they had already made, rather than to change them. When the initial clinical assessment strongly suggested a bacterial infection -correct or not-, clinicians frequently prioritized clinical judgement over test results. When test findings conflicted with clinical intuition, clinicians sometimes questioned the accuracy of the test rather than revising their prescribing decision.
Point-of-care tests were more effective in cases of genuine diagnostic uncertainty, when symptoms were non-specific. In these cases, a test result could change the prescribing decision in either direction. However, patient expectations, perceived severity of illness, timing of presentation, and cultural norms around antibiotics often outweighed test results.
“The results of our study suggest that diagnostic tests alone are not sufficient. Clinicians across six very different countries and health systems described the same behaviours; the primacy of clinical intuition, the perceived patient pressure and expectations and the difficulty of acting on a test result that conflicts with their own assessment. This tells us that the barriers to POC testing to be effective are not a local problem. They are fundamental to how clinical decisions are made. Point-of-care testing needs to be part of a broader strategy, one that includes clinician training, communication support, and clear guidance on how to act safely on test results, concluded Alike van der Velden.”
Diagnostic testing has been widely promoted in national and international action plans as a key mechanism to reduce inappropriate antibiotic use. The results of these studies suggest that diagnostics tests alone are not sufficient to reduce antibiotic prescribing. They must be combined with structured clinician training, clear guidance on the safety of following test results, and strategies to address the cognitive dissonance- the discomfort of holding conflicting information that arises when test results challenge a clinician’s initial assessment.
