| Acutely or critically ill medical inpatients |
| Better information on baseline risk assessment of thrombosis and bleeding in acutely or critically ill medical inpatients is needed, in particular whether risk varies over the course of admission |
| More information on the optimal dosing of parenteral anticoagulation to prevent VTE in acutely or critically ill medical inpatients is needed. In particular, can lower or higher doses be used in different settings (perhaps dependent on baseline risk), and should dosing be adjusted in obese patients, underweight patients, and patients with renal disease? |
| Determination of the acceptable balance between bleeding and thrombosis risk in the context of selecting the optimal VTE prophylaxis in critically ill medical patients |
| Net health benefit of mechanical prophylaxis in a lower risk medical inpatient population |
| Utility of outpatient use of mechanical prophylaxis in medical outpatients at risk of VTE |
| Direct comparisons between graduated compression stockings and pneumatic compression devices in acutely or critically ill medical inpatients |
| Impact of use of pneumatic compression devices in acutely or critically ill medical inpatients at high bleeding risk or with active bleeding |
| Better information on bleeding risk in acutely or critically ill medical inpatients to inform decisions about use of mechanical or pharmacological VTE prophylaxis |
| More direct evidence on combined mechanical and pharmacological prophylaxis compared with mechanical prophylaxis alone via clinical trials on efficacy, harms, and adherence to the intervention, particularly in high-risk medical inpatients in whom the balance of potential benefits vs harms might be more favorable than among lower-risk patients |
| Obtain patient preferences for mechanical or pharmacological prophylaxis in the hospital setting by studying feasibility, equity, and acceptability |
| Determine current utilization rate of combined mechanical and pharmacological prophylaxis in practice among acutely or critically ill medical inpatients |
| Provide more direct evidence on combined mechanical and pharmacological prophylaxis compared with mechanical prophylaxis alone via clinical trials on efficacy, harms and adherence to the intervention, particularly in high-risk medical inpatients in whom the balance of potential benefits vs harms might be more favorable than among lower-risk patients |
| Comparative effectiveness research on combined mechanical and pharmacological prophylaxis compared with mechanical prophylaxis alone in acutely or critically ill medical inpatients |
| Conduct trials of combined mechanical and pharmacological prophylaxis compared with pharmacological prophylaxis alone among very high risk patient groups |
| A systematic review of observational studies and a large comparative RCT are needed to increase the evidence available comparing pneumatic compression devices with graduated compression stockings in acutely or critically ill medical patients |
| Studies of pneumatic compression devices compared with graduated compression stockings in acutely or critically ill medical patients with contraindications to pharmacological prophylaxis or those at high bleeding risk |
| Study DOAC use among medical inpatients or for extended prophylaxis after discharge in larger trials assessing symptomatic VTE and bleeding end points in more selected patients based on predicted risk of VTE and of bleeding |
| Evaluation of lower-dose DOAC regimens in acutely ill medical inpatients or for extended use after discharge, to determine whether this might mitigate bleeding risk while preventing VTE |
| Trials of pharmacological or nonpharmacological interventions in selected high-risk medical patients at discharge |
| Studies that evaluate dose adjustments or lower doses of anticoagulants that might maximize benefit while minimizing harm when used for extended treatment to prevent VTE after hospital discharge among acutely or critically ill medical inpatients |
| Chronically ill medical inpatients or nursing home residents |
| Studies on identification of high-risk subgroups of chronically ill medical patients who could benefit from VTE prophylaxis, with consideration given to those who are immobilized |
| Studies of low-dose anticoagulant approaches, including use of DOACs or aspirin in chronically ill medical patients |
| Research on current clinical practices for VTE prevention and patient preferences for VTE prevention in chronically ill medical inpatients or nursing home residents |
| Studies on identification of high-risk subgroups of chronically ill medical patients who could benefit from VTE prophylaxis, with consideration given to those who are immobilized |
| Outpatients with minor provoking VTE risk factors |
| Development of risk-assessment methods to determine absolute risk of VTE in outpatients with minor provoking VTE risk factors |
| Trials of interventions (pharmacological or nonpharmacological) in a high-risk population of outpatients with minor provoking VTE risk factors |
| Travelers |
| Risk-assessment methods to define travelers at sufficiently high VTE risk to warrant VTE prophylaxis intervention |
| Large pragmatic trials of interventions to prevent VTE in travelers, particularly those at high VTE risk |
| Evidence on effectiveness and safety of DOACs to prevent VTE in travelers at risk of VTE |
| Acutely or critically ill medical inpatients |
| Better information on baseline risk assessment of thrombosis and bleeding in acutely or critically ill medical inpatients is needed, in particular whether risk varies over the course of admission |
| More information on the optimal dosing of parenteral anticoagulation to prevent VTE in acutely or critically ill medical inpatients is needed. In particular, can lower or higher doses be used in different settings (perhaps dependent on baseline risk), and should dosing be adjusted in obese patients, underweight patients, and patients with renal disease? |
| Determination of the acceptable balance between bleeding and thrombosis risk in the context of selecting the optimal VTE prophylaxis in critically ill medical patients |
| Net health benefit of mechanical prophylaxis in a lower risk medical inpatient population |
| Utility of outpatient use of mechanical prophylaxis in medical outpatients at risk of VTE |
| Direct comparisons between graduated compression stockings and pneumatic compression devices in acutely or critically ill medical inpatients |
| Impact of use of pneumatic compression devices in acutely or critically ill medical inpatients at high bleeding risk or with active bleeding |
| Better information on bleeding risk in acutely or critically ill medical inpatients to inform decisions about use of mechanical or pharmacological VTE prophylaxis |
| More direct evidence on combined mechanical and pharmacological prophylaxis compared with mechanical prophylaxis alone via clinical trials on efficacy, harms, and adherence to the intervention, particularly in high-risk medical inpatients in whom the balance of potential benefits vs harms might be more favorable than among lower-risk patients |
| Obtain patient preferences for mechanical or pharmacological prophylaxis in the hospital setting by studying feasibility, equity, and acceptability |
| Determine current utilization rate of combined mechanical and pharmacological prophylaxis in practice among acutely or critically ill medical inpatients |
| Provide more direct evidence on combined mechanical and pharmacological prophylaxis compared with mechanical prophylaxis alone via clinical trials on efficacy, harms and adherence to the intervention, particularly in high-risk medical inpatients in whom the balance of potential benefits vs harms might be more favorable than among lower-risk patients |
| Comparative effectiveness research on combined mechanical and pharmacological prophylaxis compared with mechanical prophylaxis alone in acutely or critically ill medical inpatients |
| Conduct trials of combined mechanical and pharmacological prophylaxis compared with pharmacological prophylaxis alone among very high risk patient groups |
| A systematic review of observational studies and a large comparative RCT are needed to increase the evidence available comparing pneumatic compression devices with graduated compression stockings in acutely or critically ill medical patients |
| Studies of pneumatic compression devices compared with graduated compression stockings in acutely or critically ill medical patients with contraindications to pharmacological prophylaxis or those at high bleeding risk |
| Study DOAC use among medical inpatients or for extended prophylaxis after discharge in larger trials assessing symptomatic VTE and bleeding end points in more selected patients based on predicted risk of VTE and of bleeding |
| Evaluation of lower-dose DOAC regimens in acutely ill medical inpatients or for extended use after discharge, to determine whether this might mitigate bleeding risk while preventing VTE |
| Trials of pharmacological or nonpharmacological interventions in selected high-risk medical patients at discharge |
| Studies that evaluate dose adjustments or lower doses of anticoagulants that might maximize benefit while minimizing harm when used for extended treatment to prevent VTE after hospital discharge among acutely or critically ill medical inpatients |
| Chronically ill medical inpatients or nursing home residents |
| Studies on identification of high-risk subgroups of chronically ill medical patients who could benefit from VTE prophylaxis, with consideration given to those who are immobilized |
| Studies of low-dose anticoagulant approaches, including use of DOACs or aspirin in chronically ill medical patients |
| Research on current clinical practices for VTE prevention and patient preferences for VTE prevention in chronically ill medical inpatients or nursing home residents |
| Studies on identification of high-risk subgroups of chronically ill medical patients who could benefit from VTE prophylaxis, with consideration given to those who are immobilized |
| Outpatients with minor provoking VTE risk factors |
| Development of risk-assessment methods to determine absolute risk of VTE in outpatients with minor provoking VTE risk factors |
| Trials of interventions (pharmacological or nonpharmacological) in a high-risk population of outpatients with minor provoking VTE risk factors |
| Travelers |
| Risk-assessment methods to define travelers at sufficiently high VTE risk to warrant VTE prophylaxis intervention |
| Large pragmatic trials of interventions to prevent VTE in travelers, particularly those at high VTE risk |
| Evidence on effectiveness and safety of DOACs to prevent VTE in travelers at risk of VTE |