Larocca 2012.

Study characteristics
Methods	Trial acronym: substudy of RV‐MM‐PI209 Design: prospective, multicentre, open‐label, randomised substudy of a phase III trial with modified intention‐to‐treat analyses of both effectiveness and safety outcomes, including participants who received ≥ 1 study dose Median follow‐up duration: 20 months
Participants	Patients with newly diagnosed multiple myeloma treated with lenalidomide and low‐dose dexamethasone induction and melphalan‐prednisone‐lenalidomide consolidation. Median age: 57 (IQR 51–61) years in aspirin group; 58 (IQR 52–62) years in LMWH group Gender, n (%) males: 87 (49%) in aspirin group; 99 (60%) in LMWH group Metastatic disease: not reported Previous VTE: 0/342 (0%) overall
Interventions	Intervention 1: LMWH, enoxaparin 40 mg/day SC Intervention 2: aspirin 100 mg/day Prophylaxis was provided during the 4 (28‐day) cycles of lenalidomide and low‐dose dexamethasone and the 6 (28‐day) cycles of melphalan‐prednisone‐lenalidomide consolidation. Median treatment duration: 3.6 months in aspirin group; 3.5 months in LMWH group
Outcomes	Primary endpoint: composite of symptomatic DVT, PE, arterial thrombosis, any acute cardiovascular event, or sudden otherwise‐unexplained death in the first 6 months after randomisation Secondary outcomes: major and minor bleeding, any complications related to thromboprophylaxis
Notes	Funding: main study (RV‐MM‐PI209) was supported by Fondazione Neoplasie Sangue Onlus, and Celgene supplied free lenalidomide. The authors declared that Celgene had no role in the study design, data analysis, data interpretation, or writing of the report. Disclosure of potential conflicts of interest: several authors declared having received honoraria or consultancy fees from various pharmaceutical companies, including Celgene. Publication format: full‐text publication
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "simple randomization sequence run by a central computer, which generated an automated assignment procedure that was concealed from the investigators in each study center." Comment: adequate method of sequence generation.
Allocation concealment (selection bias)	Low risk	Quote: "simple randomization sequence run by a central computer, which generated an automated assignment procedure that was concealed from the investigators in each study center." Comment: adequate method of allocation concealment.
Blinding (performance bias and detection bias) All outcomes	High risk	Quote: "Open‐label" study Comment: open study with no blinding of participants, physicians, and outcome assessors.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: all randomised participants were included in the analysis.
Selective reporting (reporting bias)	Low risk	Comment: all outcomes reported in the methods section were addressed in the results or discussion section.