SAGE IVD recommended fully listing total creatinine, point-of-care test in the EDL 5
• as a disease-specific IVD for use in community settings and health facilities without laboratories (Section I.b. Kidney disease);
• using a point-of-care test as assay format;
• using capillary whole blood as specimen type;
• to assess kidney function as an aid to diagnosis of kidney disease.

The application proposed point-of-care tests for creatinine. SAGE IVD members noted a creatinine point-of-care test would be a useful for screening and managing renal problems, enabling early detection and prevention of chronic kidney disease. Furthermore, awareness of kidney disease is low, ranging from 6% in low-resource settings to 20% in higher-resource settings. The test aligns well with laboratory-based measurements and minimal skills are needed for its use, making it suitable for widespread implementation. However, clinical decision-making is key in interpreting results. The devices range in cost (e.g. US$ 3000–14 000), with varying costs for test strips. Thus a detailed cost-per-result analysis (including equipment, reagents, maintenance, etc.) is needed for full understanding of cost–effectiveness. Concerns were raised about lack of: regulatory documentation in the provided submissions, although some devices have approvals (e.g. FDA approval for a sensor); clarity on cost specifics, and comparable device evaluations. Cartridge-based assays were flagged as potentially more expensive and less suitable than strip-based assays. Potential additional costs (e.g. IT system interfaces, quality assurance) were noted as a barrier to equitable pricing. Despite some initial hesitations, SAGE IVD members largely supported the tests, emphasizing their public health benefits and alignment with the goals of managing chronic kidney disease. It was recognized that endorsing the tests could stimulate market competition and reduce costs in the long term and that countries could negotiate prices.

The PoC tests for which clinical evidence was provided seem mostly to agree with lab-based measurements on average (but may be dependent on the population or reference test). Whether the range of disagreements are acceptable remains a clinical decision (see 95% limits of agreement). These disagreements may result in misclassification (misdiagnosis). Impact of using (different) PoC tests, rather than impact of (early) screening for creatinine levels, on patient-relevant or health-related outcomes does not seem to be reported. However, one systematic review [ref 27, NICE 2019] found some data where using PoC tests before conducting CT scans might influence management decisions (e.g. scans with/without constrast, or reduced dose of contrast). This systematic review concordigly did not find any data obout the impact of the test in patient-relevant outcomes (e.g. need for renal transplant therapy, hospital admissions). The cost-effectivness study reported in the [ref 27, NICE 2019] systematic review suggests that using PoC devices before contrast-enhanced CT-scanning may reduce costs arising from unnecessary delays in CT scanning appointments. Note that this concerned the outpatient non-emergency secondary care setting.There are some other primary cost-effectiveness studies but none of these cost-effectiveness analyses seem to mention measurement of creatinine by PoC tests specifically or compare PoC tests with lab tests in the model. Nonetheless, it is suggested that early or improved detection of CKD by eGFR might be cost-effective in some reports.

The selection and use of essential in vitro diagnostics: report of the fifth meeting of the WHO Strategic Advisory Group of Experts on In Vitro Diagnostics, 2024. World Health Organization. (To be published)