Evidence Table 57Aspirin – comparing dose or timing

Bibliographic referenceStudy TypeEvidence levelNo. of patientsPatients characteristicsInterventionComparisonLength of follow upOutcome measuresEffect sizeComments
Antiplatelet Trialists’ Collaboration, 199421

3 out of 55 trials 12,259,436

All of these studies were included in the guideline review.
Systematic review1+184Type of surgery: Elective orthopaedicHigher dose aspirinLower dose aspirinMajority 1 or 2 week studiesDVT Confirmed by: fibrinogen uptake test or venographyInt: 32/93
Control: 34/91
p value: 0.65 (3 studies)
Not stated what was considered a major bleed

Reported pulmonary emboli but did not state how if they were confirmed.

Not reported: QoL, survival, LoS, PTS, funding
Additional non- comparative prophylaxis:

None reported
Additional non- comparative prophylaxis:

None reported
Major bleedInt: 0/43
Control: 1/41
p value: 0.43 (2 studies)

From: Appendix D, Evidence tables

Cover of Venous Thromboembolism
Venous Thromboembolism: Reducing the Risk of Venous Thromboembolism (Deep Vein Thrombosis and Pulmonary Embolism) in Patients Admitted to Hospital.
NICE Clinical Guidelines, No. 92.
National Clinical Guideline Centre – Acute and Chronic Conditions (UK).
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