A systematic review has identified two point-of-care testing devices that meet standards for lipid measurement, potentially offering reliable alternatives to laboratory testing for NHS Health Check screenings.
In the study, published in BMJ Open, investigators from Newcastle University and collaborating institutions evaluated 22 analytical validity studies and 5 clinical validity studies covering six point-of-care testing (POCT) devices for measuring cholesterol levels. They indicated that the Cholestech LDX and Cobas b101 systems demonstrated the most consistent performance in accordance with the 1995 U.S. National Cholesterol Education Program (NCEP) recommendations.
"We found that evidence for two of the devices mostly met the requirements of the NCEP standard of evidence for bias and precision and could be recommended to general practitioners to use in the NHS Health Check Programme. These were the Cholestech LDX and the Cobas b101 system," the study authors stated.
The investigators addressed concerns raised by primary care staff about the reliability of POCT results compared with laboratory testing in the NHS Health Check Programme, which provides preventive health screenings among adults aged 40 to 74 years. The program requires measurement of nonfasting blood samples for total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and non-HDL-C (calculated by subtracting HDL-C from TC) to assess cardiovascular risk.
The investigators systematically searched Medline and Embase databases in May 2023, supplemented by Google Scholar searches and hand searching of reference lists. From 1,185 articles initially identified, they screened 876 de-duplicated articles to reach the final 22 studies included in the analysis. They assessed analytical validity studies using a modified quality appraisal tool for studies of diagnostic reliability (QAREL) and evaluated diagnostic accuracy studies using QUADAS-2.
Device performance was measured against the NCEP Laboratory Standardization Panel guidelines, which set standards for acceptable mean percent bias, coefficient of variation, and total error for TC, triglycerides (TG), HDL-C, and low-density lipoprotein cholesterol (LDL-C).
The research team found evidence for six POCT devices: Afinion AS100, Accutrend Plus, CardioChek PA, Cholestech LDX, Cobas b101, and Elemark. The evidence was unevenly distributed, with most studies focused on Cholestech LDX (n = 7), CardioChek PA (n = 8), and Accutrend Plus (n = 6).
On average, the Cholestech LDX and Cobas b101 devices reported mean percent bias, coefficient of variation, and total error ranges that met NCEP standards for TC, TG, and HDL-C measurements. In contrast, studies on the Elemark device reported coefficients of variation that did not meet any of the standards.
"Evidence of between- and within-study heterogeneity was found. Precision measures often showed systematic differences between the POCT and reference standards," the study authors noted.
The investigators acknowledged several limitations in the available evidence, including the heterogeneity in reporting formats and paucity of studies for some devices. None of the studies followed standardized reporting guidelines such as STARD (Standards for Reporting Diagnostic Accuracy Studies).
The investigators suggested that future research should consider "other evidence related to health economics and usability" to further inform the potential effectiveness and real-world applicability of these devices.
The rapid review provided reassurance regarding the analytical performance of specific POCT devices for cholesterol measurement, potentially supporting their integration into primary care settings for cardiovascular risk assessment in the NHS Health Check Programme.
The findings could guide health care professionals, managers, and researchers in selecting appropriate POCTs that meet the multifaceted requirements of their clinical settings while maintaining the accuracy necessary for effective cardiovascular risk assessment.
The study was funded by the Academic Health Science Network for the North East and North Cumbria. The authors declared having no competing interests.