Table 2.

Grading of recommendations assessment, development, and evaluation assessment.

Quality assessment							No. of patients		Effect		Quality	Importance
No of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	Cognitive decline	Control	Relative (95% CI)	Absolute
Cross-sectional study
1	Observational studies	Very seriousa	No serious inconsistency	Seriousb	Very seriousc	None	–	–	RR 1.03 (0.57 to 1.86)	–	ÅOOO VERY LOW	Critical
								0%		–
Cohort study
35	Observational studies	No serious risk of bias	No serious inconsistency	No serious indirectness	No serious imprecision	Reporting biasd strong associatione	–	–	RR 1.55 (1.33 to 1.82)	–	ÅÅOO LOW	Critical
								0%		–
RCT
1	Randomized trials	Seriousf	No serious inconsistency	No serious indirectness	No serious imprecision	None	–	-	RR 0.97 (0.65 to 1.45)	–	ÅÅÅOMODERATE	Critical
								0%		–
Case-control study
2	Observational studiesg	Seriousa	No serious inconsistency	No serious indirectness	Serioush	Reporting biasi	–		OR 1.17(0.53 to 2.61)	–	ÅOOO VERY LOW	Critical
								0%		–

^aThere are potential confounding biases, small sample sizes, and deviations from established biases caused by research design.

^bDiseases and factors coexist, and the exact causal relationship cannot be determined.

^cThe sample size is small, and the merged evidence has great inaccuracy.

^dEgger’s test may indicate publication bias.

^eEleven studies have shown that RR values are greater than 2.

^fData loss caused by missing visits.

^gCase-control.

^hWide confidence interval.

ⁱNo explanation was provided.