id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-257169-1lk737lw	Lau, C. S.	Performance of an automated chemiluminescence SARS-COV-2 IG-G Assay	2020-09-08		.txt	text/plain	4265	230	53	Methods We assessed assay precision, sensitivity, specificity, positive/negative predictive values (PPV/NPV), cross-reactivity (influenza/dengue/hepatitis B and C/rheumatoid factor/anti-nuclear/double-stranded DNA/syphilis) and sample throughput in samples from real-time polymerase chain reaction (RT-PCR) positive patients/healthcare workers (HCWs)/pre-pandemic samples. A lower COI limit for reactivity (≥0.55, using the 99th percentile COI of our controls and ROC analysis) improved diagnostic sensitivity, especially at 0-6 days POS (45.9% to 55.8%), with a small decrease in specificity (98.9%). We report on our evaluation of the Abbott Architect chemiluminescent immunoassay for SARS-CoV-2-IgG including deriving an optimised cut-off index that may be useful in testing early Covid-19 samples. An optimized COI limit for reactive samples (COI ≥0.55) (concordant values between 99th percentile of healthy controls and ROC analysis) improved the sensitivity of the assay in early infection (45.9% to 55.8% in subjects 0-6 days POS) but with a small decrease in specificity (99.8% to 98.9%).	./cache/cord-257169-1lk737lw.txt	./txt/cord-257169-1lk737lw.txt