Table 18.

—[Section 4.5] Summary of Findings: Should VKA Compared With No VKA Be Used for Thrombosis Prophylaxis in Patients With Cancer With Central Venous Catheters?¹¹⁴

Outcomes	Illustrative Comparative Risksa (95% CI)		Relative Effect (95% CI)	No. of Participants (Studies)	Quality of the Evidence (GRADE)
	Assumed Risk, no VKA	Corresponding Risk, VKA
Death	312 per 1,000	303 per 1,000 (256-359)	RR, 0.97 (0.82-1.15)	1,093 (2)	Low due to imprecisionb,c
Symptomatic DVT	90 per 1,000	57 per 1,000 (31-100)	RR, 0.63 (0.35-1.11)	1,235 (4)	Low due to imprecisionb,c
Major bleeding	2 per 1,000	14 per 1,000 (2-112)	RR, 6.93 (0.86-56.08)	1,093 (2)	Low due to imprecisionb,c; high-quality evidence in other populations

See Table 1 and 4 legends for expansion of abbreviations.

^aThe basis for the assumed risk (eg, the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

^bWe rated down for methodologic limitations. Allocation clearly concealed in three of the four studies. None of studies blinded patients, providers, or data collectors, and three studies blinded outcome adjudicators. Three studies had no problem with incomplete data. The presence of selective reporting was unclear in one study. Two studies clearly used ITT.

^cRelatively small number of events. CI includes both values suggesting no effect and values suggesting either benefit or harm.