One-on-one comparison between qCSI and NEWS scores for mortality risk assessment in patients with COVID-19

Figures & data

Table 1. Demographic and clinical characteristics for 90-day mortality.

		90-day mortality
Characteristics^a	Total No.	Non-survivors	Survivors	p value
No. with data	2961	948 (32)	2013 (68)
Age (years)	79 (66–88)	86 (79–90)	74 (60–85)	<.001
<50	260 (8.8)	10 (1.1)	250 (12.4)
50–65	460 (15.5)	36 (3.8)	424 (21.1)	<.001
66–79	774 (26.1)	194 (20.5)	580 (28.8)	<.001
>80	1467 (49.5)	708 (74.7)	759 (37.7)	<.001
Sex, female	1457 (49.2)	439 (46.3)	1018 (50.6)	.030
Urban area	1551 (52.4)	473 (49.9)	1078 (53.6)	.063
Nursing homes	1080 (36.5)	526 (55.5)	554 (27.5)	<.001
Basal evaluation
RR (breaths/min)	16 (13–25)	24 (14–26)	14 (12–22)	<.001
SpO2 (%)	94 (90–96)	90 (84–95)	95 (92–97)	<.001
FiO2 (%)	0.21 (0.21–0.21)	0.21 (0.21–0.28)	0.21 (0.21–0.21)	<.001
SBP (mmHg)	126 (111–144)	123 (106–144)	127 (114–144)	<.001
Heart rate (beats/min)	87 (76–100)	89 (75–104)	86 (76–98)	.001
Temperature (°C)	36.6 (36.2–37.3)	36.7 (36.1–37.4)	36.6 (36.2–37.2)	.207
GCS (points)	15 (15-15)	15 (13–15)	15 (15-15)	<.001
qCSI-19 SI (points)	1 (1–5)	5 (1–6)	0 (0–2)	<.001
NEWS (points)	4 (2–8)	8 (5–10)	3 (2–6)	<.001
CCI (points)	1 (1–3)	2 (1-4)	1 (1–3)	<.001
AIDS	5 (0.2)	2 (0.2)	3 (0.1)	.702
Metastatic disease	42 (1.4)	22 (2.3)	20 (1)	.004
Liver disease severe	75 (2.5)	19 (2)	56 (2.8)	.209
Lymphoma	17 (0.6)	6 (0.6)	11 (0.5)	.772
Leukemia	38 (1.3)	12 (1.3)	26 (1.3)	.954
Solid tumour localized	383 (12.9)	130 (13.7)	253 (12.6)	0.387
DM end organ damage	147 (5)	67 (7.1)	80 (4)	<.001
Severe CKD	454 (15.3)	203 (21.4)	251 (12.5)	<.001
Hemiplegia	87 (2.9)	48 (5.1)	39 (1.9)	<.001
DM uncomplicated	566 (19.1)	197 (20.8)	369 (18.3)	.114
Liver disease mild	89 (3)	28 (3)	61 (3)	.909
Peptic ulcer	84 (2.8)	34 (3.6)	50 (2.5)	.092
Connective	92 (3.1)	29 (3.1)	63 (3.1)	.918
COPD	310 (10.5)	117 (12.3)	193 (9.6)	.022
Dementia	719 (24.3)	385 (40.6)	334 (16.6)	<.001
Cerebrovascular disease	322 (10.9)	156 (16.5)	166 (8.2)	<.001
Peripheral vascular disease	255 (8.6)	100 (10.5)	155 (7.7)	.010
Congestive heart failure	437 (14.8)	190 (20)	247 (12.3)	<.001
Myocardial infarction	280 (9.5)	119 (12.6)	161 (8)	<.001
Outcomes
Hospitalization	2328 (78.6)	901 (95)	1427 (70.9)	<.001
ICU	162 (5.5)	73 (7.7)	89 (4.4)	<.001

Figures represent the descriptive statistics and p value of the comparison between non-survivors and survivors.

RR: Respiratory rate; SpO₂: pulse oximetry saturation; FiO₂: fraction of inspired oxygen; GCS: Glasgow coma scale; qCSI-19 SI: quick COVID-19 Severity Index; NEWS: National Early Warning Score; CCI: Charlson comorbidity index; AIDS: acquired immunodeficiency syndrome; DM: Diabetes mellitus; CKD: chronic kidney disease; COPD: chronic obstructive pulmonary disease; ICU: intensive care unit.

^aValues expressed as total number (fraction) and medians [25–75‰], as appropriate.

Figure 1. Predicted probability of death and observed distribution of patients across score value of NEWS for 1-day (A) and 90-day mortality (B) and qCSI for 1-day (C) and 90-day mortality (D). The grey area of the trend line corresponds to 95% confidence interval of the predicted probability of death (trend line). The bars correspond to the number of patients alive (grey) or dead (black) in the training cohort. The values within parenthesis refer to the range of score values included in each bar.

Figure 2. Predictive validity results of each model. Decision curve analysis for 1-day (A) and 90-day mortality (C) and the area under the receiver operating characteristic (ROC) curves for 1-day (B) and 90-day mortality (D) of qCSI and NEWS. Grey line corresponds to qCSI results and the black line to NEWS results.

Table 2. Predictive validity of qCSI and NEWS for different mortality time points.

	1-day	2-day	7-day	14-day	30-day	90-day
NEWS	0.825	0.823	0.792	0.780	0.779	0.777
qCSI	0.769	0.782	0.760	0.745	0.750	0.749
p Value	<.001	<.001	<.001	<.001	<.001	<.001

Figures represent the area under the receiver operating characteristic (ROC) curve (AUC) for each score, and the p value (Delong’s test) of the AUCs comparison at each time point.

NEWS: National Early Warning Score; qCOVID: quick COVID-19 Severity Index.

Table 3. Statistical details of the qCSI and NEWS for different point times analyzed.

Mortality	Specificity	Sensitivity	PPV	NPV	LR +	LR −
1-day
NEWS	72.1 (56.5–87.5)	51.5 (33.7–69.2)	32.4 (18.2–46.7)	96.7 (95.8–97.6)	8.94 (1.95–15.9)	0.55 (0.39–0.71)
qCSI	76.1 (59.6–92.4)	47.9 (28.6–67.2)	19.2 (12.9–25.5)	96.3 (95.4–97.2)	4.29 (2.48–6.09)	0.63 (0.47–0.78)
2-day
NEWS	72.5 (57.1–88)	50.4 (32.5–68.2)	39.2 (24.8–53.7)	95.2 (93.9–96.5)	10.5 (2.04–19.1)	0.56 (0.4–0.72)
qCSI	76.7 (60.3–93.1)	48.4 (29–67.8)	27.7 (19–36.5)	94.8 (93.5–96.1)	4.96 (2.78–7.13)	0.61 (0.45–0.77)
7-day
NEWS	74.1 (58.8–89.5)	45.1 (27.4–62.9)	53.1 (40.6–65.7)	88.1 (85.1–90.7)	6.76 (3.29–10.2)	0.63 (0.47–0.78)
qCSI	78.5 (62.4–94.9)	43.4 (24.1 (62.8)	48 (36.2–59.8)	87.1 (84.6–89.7)	5.93 (2.54–9.33)	0.67 (0.52–0.82)
14-day
NEWS	75.1 (59.8–90.2)	43.1 (25.4–60.6)	60.3(48.5–72.1)	83.2 (79.8–86.5)	7.5 (2.97–12.03)	0.65 (0.5–0.8)
qCSI	79.6 (63.5–95.7)	40.7 (21.5–59.8)	56.1 (44.4–67.7)	81.8 (78.8–84.9)	6.16 (2.42–9.91)	0.7 (0.56–0.84)
30-day
NEWS	75.6 (60.5–90.8)	42.2 (24.7–59.7)	65.3 (53.5–77.1)	80.2 (76.4–83.9)	6.96 (3.22–10.6)	0.66 (0.52–0.81)
qCSI	80.3 (64.3–96.3)	39.9 (20.6–59.1)	60.4 (49.6–71.2)	78.8 (75.3–82.3)	5.8 (2.71–8.89)	0.7 (0.56–0.85)
90-day
NEWS	76.3 (61.2–91.4)	41.3 (23.9–58.7)	69.7 (58.4–81.1)	76.7 (72.6–80.7)	9.3 (3.19–15.4)	0.67 (0.53–0.81)
qCSI	81.1 (65.1–97)	38.8 (19.7–57.9)	65.2 (54.7–75.6)	75.1 (71.3–79)	5.85 (3.08–8.62)	0.71 (0.57–0.85)

Figures represent different metrics derived from the area under the receiver operating characteristic (ROC) curve (AUC) for each score at each time point.

NEWS: National Early Warning Score; qCSI: quick COVID-19 Severity Index; PPV: positive predictive value; NPV: negative predictive value; LR: likelihood ratio.

Bracketed number indicate 95% confidence interval.

Data availability statement

Data are available upon a reasonable request to the corresponding author in https://figshare.com/s/445db8346441bd09aba3.