| enoxaparin versus placebo | |||
| Agnelli, 1998 | Enoxaparin, 40 mg/d subcutaneously within 24 hours postoperatively plus compression stockings for >=7 days versus compression stockings + placebo  | Elective neurosurgery, 18 years or older, without excess bleeding risk | Follow-up duration: 30 days  | 
| Melon, 1987 | Enoxaparin, 20 mg/d subcutaneously 18-24 hours postoperatively for 10 days versus placebo  | Neurosurgery, adult, 45-90 kg of weight, without excess bleeding risk | Follow-up duration: NA  | 
| nadroparin versus placebo | |||
| Nurmohamed, 1996 | Nadroparin, 7500 Institute Choay anti-Xa units per day subcutaneously 18-24 hours postoperatively plus compression for 10 days versus compression stockings + placebo  | Craniotomy or spinal surgery for tumor or injury, 18 years or older, without excess bleeding risk | Follow-up duration: 56 days  | 
| UFH versus no treatment | |||
| Cerrato, 1978 | Unfractionated heparin, 5000 IU subcutaneously 3 times a day, starting 2 hours preoperatively for +7 days versus no treatment  | Elective neurosurgery for tumors, 40 years or older | Follow-up duration: NA  | 
                    
                    
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