The strength of recommendation was categorized as strong (grade 1) or 320 Evidence-Based Medicine [ 1 4 9 # 2 C H E S T F E B R U A R Y 2 0 1 6 ] weak/conditional (grade 2). In determining the strength of the recommendation, the panel considered the balance of desirable and undesirable consequences (typically tradeoff between recurrent VTE and bleeding events), quality of evidence, resource implications, and patients average values and preferences for different outcomes and The chair drafted the recommendations after the entire panel had reviewed the evidence and discussed the recommendation. Recommendations were then revised over a series of conference calls and through e-mail exchanges with the entire panel. A major aim was to ensure recommendations were speci c and unambiguous. Methods for Achieving Consensus We used a modi ed Delphi technique17,18 to achieve consensus on each recommendation. This technique aims to minimize group interaction bias and to maintain anonymity among respondents. Using an online survey (www.surveymonkey.com), panelists without a primary COI voted their level of agreement with each recommendation (including quality of evidence and strength of recommendation) based on a 5-point scale derived from the GRADE grid (strongly agree, weakly agree, neutral, weakly disagree, strongly Each panelist could also provide open-ended feedback on each recommendation with suggested wording edits or general remarks. To achieve consensus and be included in the nal manuscript, each recommendation had to have at least 80% agreement (strong or weak) with a response rate of at least 75% of eligible panel members. All recommendations achieved consensus in the rst round. We then used an iterative approach that involved review by, and approval from, all panel members for the writing of this manuscript. 