Over the past few decades, diagnostic technologies have evolved and a growing number of Point of Care Tests are now available in the primary care setting. But which tests do GPs want most? And how do we evaluate which devices are worth implementing?
In this webinar, Dr. Jan Verbakel outlines the framework the EPI Centre uses to evaluate new technologies and shows how POCT within a primary care setting could reduce unnecessary antibiotic prescribing in children. The views shared in the webinar have been summarised below.
The evolution of Point of Care Testing (POCT) in primary care
Clinical practice has evolved from the traditional view of a GP relying on ‘low-tech’ clinical reasoning into a practice that involves Point of Care Tests, such as troponin, HbA1c, CRP, D-dimers, urine dipsticks – and recently, Covid-19 testing.
As Dr. Jan Verbakel highlights from a study performed amongst GPs in Australia, Belgium, The Netherlands, UK and USA1, most GP's are using urine pregnancy tests, urine dipstick tests and blood glucose testing. However, they would like to be able to test for UTIs, pulmonary embolism, acute cardiac markers and infectious disease.
Evaluating POCT in primary care
In his role at Oxford University, Dr. Jan Verbakel performs ‘horizon scanning’ to identify new and emerging diagnostic technologies that are relevant to primary care in the NHS. Utilising the Horvath Framework, his research shows that while some disease areas are covered for analytical and clinical performance, there’s very little evidence on the clinical effectiveness and cost-effectiveness of new technologies – and the median time for completing the evaluation cycle is comparable to developing a new drug2.
In addition, POCT faces the following challenges in primary care:
- Complexity of data management and oversight
- Is faster always better?
- Verification and monitoring of analytical performance
- Complicated by multiple instruments and cartridges
The EPI Centre aims to evaluate primary care innovations for analytical performance, clinical performance, clinical effectiveness, cost-effectiveness and the broader impact within the primary care setting.
Evaluating POCT: CRP and antimicrobial resistance
Children are at high-risk for unnecessary antibiotic prescribing due to diagnostic uncertainty. In fact, in Belgium, almost every child receives one antibiotic prescription per year. Could POCT be used to support better targeting of antibiotic prescribing?
- C-reactive protein (CRP) is an acute-phase protein produced by the liver in response to local inflammation.
- A systematic review showed that CRP could be a promising biomarker for detecting serious infection in children. Two devices available at the time were found to be analytically and clinically accurate.
- A review from the Cochrane Library3 looked at the value of CRP POCT to guide antibiotic prescribing and found a reduction of more than 20% when using POCT in primary care. This led to the introduction of CRP POCT within the NICE guidelines.
- Clinical performance of CRP POCT in children: Some discrepancies between test and lab, but not considered clinically relevant.
- Impact on patient-relevant outcomes: A trial showed applying CRP POCT enabled physicians to better determine which children needed further testing.
- Several studies have confirmed that CRP POCT may better target antibiotic prescribing for children with acute RTIs, but more research is urgently needed.
- Dr. Jan Verbakel has initiated the ARON trial, which applies a clinical algorithm, including CRP POCT and safety netting advice, to avoid unnecessary prescribing in children – the trial is currently recruiting, and the results will be presented soon.
Evaluating POCT: Paediatric urinary tract infection
Not all POCT tests deliver patient-relevant outcomes.
- ERNIE4 was a prospective cross-sectional diagnostic accuracy study held at 39 general practices and two emergency departments. It involved the systematic urine sampling of acutely ill children.
- The aim was to use a high sensitivity test and rule out a urine culture if the test was negative.
- The study considered three different POC tests, but unfortunately, while the specificity was quite high, the sensitivity in all tests was not high enough to rule out a UTI.
What makes the perfect POCT Test?
Dr. Jan Verbakel concludes his presentation by outlining the features of the ideal POCT test. His must-haves are:
- Accurate and reliable
- Impacts patient-relevant outcomes
- Supports clinical decision-making
- Easy to use
He also outlines some features that are ‘nice to have’:
- Portability (fits in the doctor’s bag)
- Allows for multiple readings, fast results (2mins, max 5 mins)
- Allows linkage with the patient’s electronic health record