Clinical accuracy of instrument-based SARS-CoV-2 antigen diagnostic tests: a systematic review and meta-analysis.

BACKGROUND: During the COVID-19 pandemic, antigen diagnostic tests were frequently used for screening, triage, and diagnosis. Novel instrument-based antigen tests (iAg tests) hold the promise of outperforming their instrument-free, visually-read counterparts. Here, we provide a systematic review and meta-analysis of the SARS-CoV-2 iAg tests' clinical accuracy. METHODS: We systematically searched MEDLINE (via PubMed), Web of Science, medRxiv, and bioRxiv for articles published before November 7th, 2022, evaluating the accuracy of iAg tests for SARS-CoV-2 detection. We performed a random effects meta-analysis to estimate sensitivity and specificity and used the QUADAS-2 tool to assess study quality and risk of bias. Sub-group analysis was conducted based on Ct value range, IFU-conformity, age, symptom presence and duration, and the variant of concern. RESULTS: We screened the titles and abstracts of 20,431 articles and included 114 publications that fulfilled the inclusion criteria. Additionally, we incorporated three articles sourced from the FIND website, totaling 117 studies encompassing 95,181 individuals, which evaluated the clinical accuracy of 24 commercial COVID-19 iAg tests. The studies varied in risk of bias but showed high applicability. Of 24 iAg tests from 99 studies assessed in the meta-analysis, the pooled sensitivity and specificity compared to molecular testing of a paired NP swab sample were 76.7% (95% CI 73.5 to 79.7) and 98.4% (95% CI 98.0 to 98.7), respectively. Higher sensitivity was noted in individuals with high viral load (99.6% [95% CI 96.8 to 100] at Ct-level ≤ 20) and within the first week of symptom onset (84.6% [95% CI 78.2 to 89.3]), but did not differ between tests conducted as per manufacturer's instructions and those conducted differently, or between point-of-care and lab-based testing. CONCLUSION: Overall, iAg tests have a high pooled specificity but a moderate pooled sensitivity, according to our analysis. The pooled sensitivity increases with lower Ct-values (a proxy for viral load), or within the first week of symptom onset, enabling reliable identification of most COVID-19 cases and highlighting the importance of context in test selection. The study underscores the need for careful evaluation considering performance variations and operational features of iAg tests.

Comparing SARS-CoV-2 antigen-detection rapid diagnostic tests for COVID-19 self-testing/self-sampling with molecular and professional-use tests: a systematic review and meta-analysis.

Self-testing is an effective tool to bridge the testing gap for several infectious diseases; however, its performance in detecting SARS-CoV-2 using antigen-detection rapid diagnostic tests (Ag-RDTs) has not been systematically reviewed. This study aimed to inform WHO guidelines by evaluating the accuracy of COVID-19 self-testing and self-sampling coupled with professional Ag-RDT conduct and interpretation. Articles on this topic were searched until November 7th, 2022. Concordance between self-testing/self-sampling and fully professional-use Ag-RDTs was assessed using Cohen's kappa. Bivariate meta-analysis yielded pooled performance estimates. Quality and certainty of evidence were evaluated using QUADAS-2 and GRADE tools. Among 43 studies included, twelve reported on self-testing, and 31 assessed self-sampling only. Around 49.6% showed low risk of bias. Overall concordance with professional-use Ag-RDTs was high (kappa 0.91 [95% confidence interval (CI) 0.88-0.94]). Comparing self-testing/self-sampling to molecular testing, the pooled sensitivity and specificity were 70.5% (95% CI 64.3-76.0) and 99.4% (95% CI 99.1-99.6), respectively. Higher sensitivity (i.e., 93.6% [95% CI 90.4-96.8] for Ct < 25) was estimated in subgroups with higher viral loads using Ct values as a proxy. Despite high heterogeneity among studies, COVID-19 self-testing/self-sampling exhibits high concordance with professional-use Ag-RDTs. This suggests that self-testing/self-sampling can be offered as part of COVID-19 testing strategies.Trial registration: PROSPERO: CRD42021250706.

Implementation of hyperspectral imaging in a trauma resuscitation room: a randomized controlled trial.

BACKGROUND: Hyperspectral imaging (HSI) is a novel imaging technology with the ability to assess microcirculatory impairment. We aimed to assess feasibility of performing HSI, a noninvasive, contactless method to assess microcirculatory alterations, during trauma resuscitation care. METHODS: This randomized controlled clinical trial was conducted in a dedicated trauma resuscitation room of a level one trauma center. We included adult patients who were admitted to the trauma resuscitation room. Patients were allocated in a 1:1 ratio to the HSI group (intervention) or control group. In addition to the standard of care, patients in the intervention group had two hyperspectral recordings (HSR) of their hand palm taken. Primary outcomes were the treatment duration of the primary survey (until end of ABCDE-evaluation, ultrasound and evaluation by the trauma team) and the total resuscitation room care (until transport to definitive care) as well as the ability to perform measurements from all HSR. Secondary outcomes were analyses from the intervention group compared to HSI measurements of 26 healthy volunteers including an analysis based on the ISS (Injury severity score) (< 16 vs. ≥ 16). Care givers, and those assessing the outcomes were blinded to group assignment. RESULTS: Our final analysis included 51 patients, with 25 and 26 allocated to the control and intervention group, respectively. There was a statistically significant shorter median duration of the primary survey in the control group (03:22 min [Q1-Q3 03:00-03:51]) compared to the intervention group (03:59 min [Q1-Q3 03:29-04:35]) with a difference of -37 s (95% CI -66 to -12). Total resuscitation room care was longer in the control group, but without significance: 60 s (95% CI -60 to 180). From 52 HSI, we were able to perform hyperspectral measurements on all images, with significant differences between injured patients and healthy volunteers. CONCLUSION: HSI proved to be feasible during resuscitation room care and can provide valuable information on the microcirculatory state. Trial registration DRKS DRKS00024047- www.drks.de . Registered on 13th April 2021.