Diagnostic accuracy of symptoms as a diagnostic tool for SARS-CoV 2 infection: a cross-sectional study in a cohort of 2,173 patients

Table 4 Diagnostic accuracy of the diagnostic symptoms scale*

Numbers of symptoms	Sensitivity %	Specificity %	PPV %	NPV %	LR+	LR-	Accuracy	P^a	AUC
≥ 2 symptoms [95% CI]	83.45 [81.17–85.55]	32.86 [29.94–35.89]	59.06 [57.83–60.28]	63.11 [59.37–66.69]	1.24 [1.18–1.31]	0.50 [0.43–0.59]	60.04 [57.92–62.2]	< 0.001	0.58 [0.56–0.60]
≥ 3 symptoms [95% CI]	67.39 [64.59–70.10]	58.24 [55.10–61.34]	65.18 [63.25–67.06]	60.63 [58.26–62.96]	1.61 [1.48–1.76]	0.56 [0.51–0.62]	63.16 [61.07–65.21]	< 0.001	0.62 [0.60–0.64]
≥ 4 symptoms [95% CI]	49.69 [46.76–52.63]	80.08 [77.45–82.53]	76.32 [71.60–76.86]	57.85 [56.25–59.44]	2.49 [2.17–2.86]	0.63 [0.59–0.67]	63.76 [61.68–65.81]	< 0.001	0.64 [0.62–0.66]
≥ 5 symptoms % (95% CI)	27.99 [25.4–30.68]	93.23 [91.48–94.71]	82.73 [78.88–86.01]	52.75 [51.75–53.74]	4.13 [3.22–5.30]	0.77 [0.74–0.80]	58.19 [56.07–60.30]	< 0.001	0.60 [0.58–0.62]
≥ 6 symptoms % (95% CI)	11.16 [9.40–13.13]	97.67 [96.53–98.52]	84.77 [78.26–89.59]	48.66 [48.10–49.23]	4.8 [3.10–7.42]	0.91 [0.89–0.93]	51.22 [49.07–53.36]	< 0.001	0.54 [0.52–0.56]

Abbreviations: PPV positive predictive value, NPV negative predictive value, LR+ positive likelihood ratio, LR- negative likelihood ratio, OR odds ratio, 95% CI 95% confidence interval
* Symptoms scale that included Fever, cough, anosmia, dyspnea and oxygen saturation < 93%, and headache
^aP Value estimated with Pearson’s X² test

ISSN: 1471-2334