. 2012 Feb;141(2 Suppl):e195S–e226S. doi: 10.1378/chest.11-2296

Table 14.

—[Section 3.4.4] Summary of Findings: Should LMWH vs Unfractionated Heparin Be Used for DVT Prevention in Critically Ill Adult Patients?^12,13,72

Outcome	Anticipated Absolute Effects		Relative Effect (95% CI)	No. of Participants (Studies) Follow-up	Quality of the Evidence (GRADE)
Outcome	Risk with UFH	Risk Difference With LMWH (95% CI)	Relative Effect (95% CI)	No. of Participants (Studies) Follow-up	Quality of the Evidence (GRADE)
Symptomatic DVT	25 per 1,000	3 fewer per 1,000 (from 10 fewer to 6 more)	RR, 0.87 (0.60-1.25)	4,722 (2 RCTs) 7-28 d	Moderate due to imprecision^a
Symptomatic pulmonary embolism	20 per 1,000	8 fewer per 1,000 (13.2 fewer to 0.6 fewer)	RR, 0.58 (0.34-0.97)	3,746 (1 RCT) 7 d	Moderate due to imprecision^a
Major bleeding	55 per 1,000	2 fewer per 1,000 (from 14 fewer to 14 more)	RR, 0.97 (0.75-1.26)	3,902 (2 RCTs) 7-47 d	Moderate due to imprecision^a
Death	159 per 1,000	10 fewer per 1,000 (from 30 fewer to 14 more)	RR, 0.94 (0.81-1.09)	3,902 (2 RCTs) 7-47 d	Moderate due to imprecision^a
Heparin-induced thrombocytopenia	6 per 1,000	3 fewer per 1,000 (from 5 fewer to 1 more)	RR, 0.42 (0.15-1.18)	3,746 (1 RCT) 7 d	Moderate due to imprecision^a

See Table 1 and 4 legends for expansion of abbreviations.

We will consider the presence of serious imprecision when there are <300 events in total (events in treatment and control patients) or when CIs include appreciable harms and benefits.