Table 2.

Evidence profile for different outcomes

No of studies	Certainty assessment						Effect			Certainty	Importance
	Study design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	No of events	No of individuals	Relative (95% CI)
Hospitalization (Fernandez Villalobos 2020) [50]
8	Observational studies	Seriousa	Not seriousb	Not serious	Not serious	None	176	362	RR 1.63 (1.03–2.58)	⨁⨁⨁◯ Moderate	Important
Mortality in hospitalized patients (Dorjee 2020) [46]
23	Observational studies	Seriousc	Not seriousd	Not serious	Not serious	None			RR 2.52 (2.1–3.0)	⨁⨁⨁◯ Moderate	Critical
Pooled Hazard ratio for mortality (Sept 2020 till Jan 2021)
20	Observational studies	Seriouse	Not seriousb	Not serious	Not serious	None	17,163	1,718,678	HR 1.48 (1.33–1.65)	⨁⨁⨁◯ Moderate	Critical
Pooled Odds ratio for mortality (Sept 2020 till Jan 2021)
24	Observational studies	Seriousf	Not serious	Not serious	Not serious	None	8929	26,267	OR 1.77 (1.54–2.02)	⨁⨁⨁◯ Moderate	Critical
Pooled Risk ratio for mortality (Sept 2020 till Jan 2021)
3	Observational studies	Serious g	Not serious	Not serious	serioush	None	9493	50,411	RR 1.6 (0.88–2.92)	⨁⨁◯◯ Low	Critical
Severe disease (Dorjee 2020) [46]i
27	Observational studies	Seriousj	Not seriousb	Not serious	Not serious	None			RR 1.56 (1.3–1.86)	⨁⨁⨁◯ Moderate	Important
ICU admission (Degarege, 2020) [62]
2	Observational studies	Seriousk	Not serious	Not serious	Seriousl	None			OR 1.37 (0.8–1.86)	⨁⨁◯◯ Low	Important

^aThe included studies were judged to be at high risk of bias in the domains of bias due to missing data and at moderate risk of bias in the domains of bias due to confounding and bias due to selection of participants and follow–up

^bDespite the presence of high statistical heterogeneity as reflected by the I² of > 80%, most of the effect estimates suggest the same direction of effect

^cSome of the included studies were judged to be at high risk of bias in the domains of selection, comparability and outcome bias using Newcastle Ottawa tool

^dEven though I² is 72%, the effect estimates point toward increase mortality in patients with CKD

^eDifferent included studies were judged to be at high risk of bias in the domains of study participation, prognostic factor measurement, outcome measurement and study confounding

^fSome of the included studies were judged to be at high risk of bias in the domains of prognostic factor measurement and study confounding

^gDominguez–Ramirez, which contributes to 33% of the weight, was judged to be at high risk of bias in the domain of prognostic factor measurement

^hThe effect estimates cross the value of no effect suggesting both possible high and low risk

ⁱSevere disease for any of 1) the study classified COVID–19 disease as severe or critical, 2) intensive care unit (ICU) admission, 3) acute respiratory distress syndrome, or 4) mechanical ventilation. Severe disease was defined by studies as respiratory rate > 30 per minute, oxygen saturation < 93%, and PaO2/FiO2 < 300 and/or lung infiltrates > 50% within 24–48 h

^jSome of the included studies were judged to be at high risk of bias in the domains of selection, comparability and outcome bias using Newcastle Ottawa tool

^kThe included studies with highest weight (98% weight) were judged to be at high risk of bias in the domains of selection bias and data collection

^lThe effect estimates cross the value of no effect suggesting both possible high and low risk