"Increasing ascorbate caused spurious decreases in blood lactate measured by the colorimetric assay and two POC devices (Epoc® and the StatStrip Xpress®). False increases in blood lactate were observed with one POC device (iSTAT 1®) and with two blood gas analysers (RAPIDPoint® 500 and Radiometer ABL90 Flex), although the latter was not clinically significant. The StatProfile® Prime Plus blood gas analyser showed no interference. For glucose, increasing ascorbate caused spurious elevations in glucose with four POC glucometers (FreeStyle Optium Neo, StatStrip Xpress®, HemoCue® Glucose 201, and Epoc®) and a false decrease with the RAPIDPoint® 500. No interference was observed with the StatProfile® Prime Plus, Radiometer ABL90 Flex, or laboratory assay. At pharmacologic concentrations, ascorbate can cause both falsely high and low lactate and glucose readings, depending on the device used. These findings help inform the selection of appropriate devices for future clinical trials of mega-dose ascorbate."

These cases demonstrate that point-of-care (POCT) beta-HCG tests can produce false-positive results due to immunoassay interference, potentially leading to unnecessary invasive procedures like diagnostic laparoscopy. When POCT results conflict with clinical findings or imaging, clinicians must promptly validate them via formal laboratory analysis to ensure patient safety and avoid misdiagnosis.

"Most healthcare professionals use and prefer accurate blood sampling devices, suggesting implementing a recommendation to use these is likely feasible. However, guidance on the timing of testing is needed."

"We noted a decrease in ionized calcium measurements post-reinfusion. Future studies should assess changes after larger volume transfusions and assess repletion methods."

Umbilical cord arterial blood lactate demonstrates good diagnostic accuracy for perinatal asphyxia and is a strong predictor of short-term adverse neonatal outcomes among term neonates. Given its high sensitivity and specificity at defined cut-off values, UCAB lactate represents a simple, cost-effective, and practical alternative to blood gas analysis, particularly in low- and middle-income settings where access to advanced laboratory facilities is limited.

"The POCT devices were acceptable and practical for use by our specialist paramedic participants. The results of this feasibility study should inform the design of a larger study to test the impact of using POCT, to understand challenges in recruitment and retention where POCT is utilised and to determine the clinical presentations where POCT can be applied."

"This study identified two hs-cTnI thresholds (<5 ng/L or <8 ng/L) to identify patients at low risk and two thresholds (>25 ng/L and >60 ng/L) to identify patients at high risk for MI. Our findings provide promise for improving care in rural and inner-city medical settings."

"With the TnI-Nx assay, we successfully demonstrated an approach using synthetic data generation to derive low-risk thresholds for safe and effective screening."

The noninvasive DBC methodology demonstrated variable agreement with the invasive i-STAT® POCT device across measured blood parameters in healthy participants. While acceptable concordance was observed for selected analytes, systematic differences were identified for hemoglobin, potassium, and sodium. Overall, the results indicate potential for noninvasive real-time blood value assessment, warranting further validation in larger and clinically diverse populations.

"The difference between the mean SmO2 and ScvO2 was not statistically significant and the mean bias between SmO2 and ScvO2 is low. Despite this, the substantially large standard deviation and limits of agreement preclude the use of SmO2 as a direct surrogate of ScvO2."

"This small feasibility study observed that training selected patients to competently use hand-held devices to self-test kidney function at home is possible. Self-test creatinine results showed good analytical and clinical agreement with standard clinic test results. Self-test potassium results showed poorer agreement with standard clinic test results; however, patient self-use of i-STATs at home was not a statistically significant source of difference between paired potassium test results."

"In conclusion, the fingerstick creatinine test may be considered for early use in patients presenting to the ED, as it is easily applicable in examination and treatment management and has strong agreement rates with laboratory values."

"Available cross-validation data demonstrate substantial differences between ACT platforms [Hemochron, Medtronic ACT Plus and i-STAT]. Real-world heparin administration strategies and ACT targets vary markedly by platform. These findings challenge the assumption of universal ACT targets and highlight the need for platform-specific interpretation."

"The i-STAT analyzers produce more reproducible ACT results [than the Hemochron], but the target range should be lowered to 200 to 250 seconds. This range appears to provide adequate and safe heparin therapy, confirmed by anti-Xa assay results and clinical outcome."

"These findings emphasize that the clinical application of POC troponin assays [Atellica VTLi, i-STAT, AQT System. Cobas h 232, CArdio3] in AMI diagnosis must consider the test’s robust specificity (≈90%) alongside its limited sensitivity (<50%)."

"No point-of-care Hgb device [HemoCue®, i-STAT®, Rad-67®]demonstrated limits of agreement that were smaller than the agreement difference of 4 g L-1. Despite this, HemoCue can be safely used to inform transfusion decisions in surgery, given its error probability of <4% in transfusion scenarios."

"Accuracy of meters [Contour Next, Accu-Chek Guide, FreeStyle Optium Neo and LifeSmart] was higher when using venous samples than when using capillary samples. Contour Next and Accu-Chek Guide meters met accuracy standards in all analyses."

Point-of-care haemoglobin testing can support transfusion decision-making in major noncardiac surgery, but its results should be interpreted with caution. Although none of the evaluated devices met predefined agreement thresholds with laboratory measurements, the HemoCue® demonstrated the lowest risk of prompting inappropriate red cell transfusion. Awareness of patient-, sample-, and device-related factors remains essential to ensure safe and informed clinical use of POC haemoglobin measurements.

"The observed similarity in performance between the two devices [Abbott i-STAT® and the Nova Biomedical Lactate (LA) Plus™ meter] suggests that both are capable of reliably measuring lactate levels in a trauma situation. The LA Plus™ meter provides fast results with only one drop of blood. This study supports the prehospital use of POC devices."

"The lactate Statstrip and iSTAT-1 POCT analyzers were analytically equivalent. The clinical verification study showed that lactate is a good predictor of fetal distress, although more false positive results were found in our limited dataset. However, unnecessary interventions due to failed pH measurements might be prevented when a lactate measurement is introduced."

We demonstrated that laboratory-based FPG has the potential to be used as a diagnostic test for GDM and that the POC glucometers [i-STAT, Xpress, LDX, VivaChek-Ino, Accu-Chek Active, StatStrip, Codefree] cannot replace OGTT laboratory-based measurements.

"Both hCG POCT devices [i-STAT 1 (Abbott), AQT 90 FLEX (Radiometer)] were verified for use in clinical practice. Practical factors must also be considered when choosing which device to use in each unit."

"This comparison study of pH, pCO2, pO2, and lactate measurements between Nova pHOx plus L® and i‐STAT® analyzers showed good agreement. However, lactate measurement results >8 mmol/L on the i‐STAT® analyzer should be interpreted with caution."

"Key pointsThe reliability of five common portable blood lactate analysers [Lactate Pro, Lactate Pro2, Lactate Scout+, Xpress™, and Edge] were generally <0.5 mM for concentrations in the range of ~1.0-10 mM.For all five portable analysers, the analytical error within a brand was much smaller than the biological variation in blood lactate (BLa).Compared with a criterion blood lactate analyser, there was a tendency for all portable analysers to under-read (i.e. a negative bias), which was particularly evident at the highest concentrations (BLa ~15-23 mM).The practical application of these negative biases would overestimate the ability of the athlete and prescribe a training intensity that would be too high."

"The i-STAT hematocrit and hemoglobin performs well when compared to the hematocrit reference method and other common methods for both hematocrit and hemoglobin [RAPIDLab 1200, Sysmex XE5000, and manual spun hematocrit]. Some differences between non-reference methods may be observed, but these were not considered clinically significant."

"False-positive hs-cTnI results continue to represent a significant diagnostic challenge in the era of advanced analytical assays. Clinicians should remain vigilant when laboratory findings conflict with clinical presentations. Targeted interference investigations and confirmation through alternative assay platforms can mitigate organizational and patient risk."

"A 0/2-hour protocol using the Abbott i-STAT® hs-TnI assay safely risk stratified emergency patients with suspected ACS and had comparable performance to two central laboratory-based assays. The use of POC testing supports timely results and may improve the time to clinical decision-making."

"The whole blood POC i-STAT hs-TnI assay demonstrated performance characteristics similar to other hs-cTn assays and achieved high sensitivity and NPV for initial measurements <LoQ and <5.0 ng/L."

"We concluded that the iSTAT-1 contemporary troponin I concentrations were concordant with hs-TnI values only if measured within 2 h."

The study highlights a significant lack of comparability between B-type natriuretic peptide (BNP) measurements obtained from the i-STAT point-of-care system and the Beckman DXI 800 laboratory analyzer. Research involving 88 patients demonstrated a strong positive bias in the i-STAT results, a finding further confirmed by simultaneous sample analysis. Because these discordant values can lead to clinical confusion and potentially impact patient management, the authors conclude that these two testing methods should not be used interchangeably in a clinical setting.

"In conclusion, the fingerstick creatinine test may be considered for early use in patients presenting to the ED, as it is easily applicable in examination and treatment management and has strong agreement rates with laboratory values."

"All hCG results from the i-STAT®1 analyzer were clinically concordant with the central laboratory method, supporting its application in an EPU setting using established clinical decision thresholds. However, further verification through larger-scale studies is necessary before the i-STAT®1 analyzer can be integrated into clinical practice."