Table 3.

PLR Ratio in Various Studies.^63–86

Authors	Study Group	Control Group	PLR Values		P value	Cut-off	AUC	Specificity (%)	Sensitivity (%)	Observations
	N	N	Study	Control
Bilge et al 202166	n=75 (Cancers)	n=111 (No cancers)	303.89	242.56	NS	-	-	-	-	There is no statistically significant differences in the PLR ratio between the control group and the study group.
Waris et al 202190	Mild n=52 Moderate n=24 Severe n=9 Critical n=16		Mild=131.5 Moderate=180.6 Severe=139.5 Critical=238.3		<0.001	-	-	-	-	PLR can be helpful for clinicians to identify potentially severe cases at early stages, initiate effective management in time, and conduct early triage which may reduce the overall mortality of COVID-19 patients.
Zhao et al 202063	Severe n=74	Mild n=211	237	229	<0.001	274	0.69	-	-	PLR reflects the intensity of inflammation and is associated with severity of patients with COVID-19.
Gujar et al 202164	ICU n=264	ISOLATION n=577	28.4	9.5	0.001	9.4	0.826	-	-	PLR can predict severe illness with high accuracy.
López-Escobar et al 202178	Non-survivors n=321	Survivors n=1767	2.4	1.9	<0.0001	2.98	-	78	44	PLR is higher at admission in patients who died compared with patients who survived, but they do not maintain significance after more complex model of multivariable adjustment.
Velazquez et al 202179	ICU n=185	Non-ICU n=2069	2.0	1.9	0.023	2.5	-	66	47	PLR shows no significant association with ICU admission in the stratified analysis.
Acar et al 202065	Non-survivors n=19	Survivors n=129	427.9	261.5	≤0.05	289.9	0.742	68.9	57.8	PLR is associated with disease mortality and can be used to predict disease progression and mortality. Increased PLR reflects an inflammation and can also indicates a poor prognosis. PLR in COVID-19 can assist in the diagnosis of prediction of mortality.
Ramos-Peñafiel et al 202067	Death n=54 0648	Alive n=71	419	338	0.192	-	-	-	-	PLR can predicts SARS-CoV-2 infection-associated mortality. PLR may be used in combination as indicators of the inflammatory and immunological status.
Citu et al 202281	Deaths n=17	Survivors n=91	345 ± 235	324 ± 219	0.71	-	-	-	-	AUC for PLR have no statistically significant discriminatory value.
Moisa et al 202182	Group 1 -patients on IMV upon ICU admission n=33 Group −2 IMV during ICU-LOS n=134 Group 3 - non-IMV during ICU-LOS n=105		Group 1=489 Group 2=566 Group 3=342		<0.0001	-	-	-	-	PLR is found to be an independent predictor for IMV need, but with lower hazard ratio value.
	Non-survivors n=142	Survivors n=130	G: 579 K: 351		<0.0001	-	-	-	-
Fois et al 202086	Non-survivors n=29	Survivors n=90	265	214	0.24	240	0.572	58	59	There are no statistically significant differences in PLR ratio between the control group and the study group. PLR ratio shows a lower diagnostic efficiency than SII.
Jain et al 202170	Severe n=29	Non-severe n=162	204	121	<0.001	115.3	115.3	62	79	PLR is significantly higher in severe COVID-19 patients than non-severe patients. The cut off for PLR is 115.3 and can classify the patients into severe and non-severe categories.

Abbreviations: ICU, intensive care unit patients; non-ICU, non-intensive care unit patients; IMV, invasive mechanical ventilation; ICU-LOS, ICU length of stay.