| First author [Ref.] | Design | Risk of bias (exposure, patient selection, consecutive, follow-up, outcome) | Definition of outpatient treatment or early discharge | Outcome measures and methods | Patients n | Age years | Males | Malignancies |
| Agterof [4] | Prospective cohort | Yes, yes, yes, yes, yes | Discharged immediately from ED or within 24 h after admission | Recurrent VTE: new intraluminal filling defect on CT, pulmonary angiogram, V′/Q′, autopsy or extension of DVT on CUS Major bleeding: according to ISTH criteria [30] Mortality: independent steering committee | 152 outpatients | 53±14 | 74 (49) | 20 (13) |
| Aujesky [5] | RCT | Yes, yes, yes, yes, yes | Discharged from ED or within 24 h of randomisation | Recurrent VTE: new intraluminal filling defect on CT, pulmonary angiogram, autopsy or extension of DVT on CUS Major bleeding: according to ISTH criteria [30] Mortality: independent steering committee | 171 outpatients 168 inpatients | 47±16 | 84 (49) | 1 (1) |
| Beer [20] | Prospective cohort | Unclear, yes, no, unclear, unclear | Unclear | Not described | 43 outpatients 54 inpatients | |||
| Davies [21] | Prospective cohort | No, yes, unclear, yes, yes | Diagnosis of PE confirmed within 72 h of initial assessment | Thromboembolic complications (with objective confirmation) | 157 early discharge | 58 | 86 (55) | |
| Erkens [6] | Retrospective cohort | Yes, yes, yes, yes, yes | Sent home from ED | Recurrent VTE: new intraluminal filling defect on CT, pulmonary angiogram, V′/Q′, autopsy or extension of DVT on CUS Major bleeding: according to ISTH criteria [30] Mortality: Consensus of two investigators based on clinical records | 260 outpatients | 55±17 | 132 (51) | 83 (32) |
| Kovacs [22] | Prospective cohort | Yes, yes, unclear, unclear, yes | Unclear | Recurrent VTE: new intraluminal filling defect on CT, pulmonary angiogram, V′/Q′, autopsy or extension of DVT on CUS Major bleeding: according previous reported criteria [31] | 81 outpatients 27 early discharge | 57 | 25 (23) | |
| Kovacs [7] | Retrospective cohort | Unclear, yes, unclear, yes, yes | Unclear | Recurrent VTE: new intraluminal filling defect on CT, pulmonary angiogram, V′/Q′, autopsy or extension of DVT on CUS Major bleeding: according to ISTH criteria [30] Mortality: not described | 314 outpatients | 54±18 | 130 (41) | 62 (20) |
| Lui [23] | Retrospective cohort | Yes, yes, yes, yes, unclear | Sent to “hospital in the home” within 24 h of arrival¶ | Death, unplanned return to hospital, unplanned staff callout, complications (recurrent PE, bleeding episode or other); methods not described | 21 outpatients | 56 | 9 (43) | 1 (5) |
| Olsson [24] | Prospective cohort | Yes, yes, no, yes, yes | Unclear | Recurrent thromboembolism: V′/Q′ scan | 102 outpatients | 63 | 45 (44) | |
| Ong [25] | Retrospective cohort | Yes, yes, no, yes, yes | Admitted directly into ambulant care programme via GP, specialist or ED | Recurrent VTE: new intraluminal filling defect on CT, pulmonary angiogram, V′/Q′, autopsy or extension of DVT on CUS Major bleeding: according to ISTH criteria [30] Mortality: clinical records | 60 outpatients 70 inpatients | |||
| Otero [26] | RCT | Yes, yes, no, yes, yes | Patients were randomised to hospitalisation or early discharge Early discharge patients were discharged on day 3 (with TTE) or on day 5 (if TTE was not available) | Recurrent VTE: new intraluminal filling defect on CT or extension of DVT on CUS Major bleeding: according to ISTH criteria [30] Mortality: clinical records | 132 inpatients | 60±17 | 65 (49) | 6 (5) |
| Rodriguez-Cerrillo [27] | Prospective cohort study | Yes, yes, no, unclear, unclear | Unclear | Recurrent VTE: unclear how diagnosis was established Major bleeding: according to ISTH criteria [30] Mortality: methods not described | 30 outpatients 31 inpatients | 67 | 26 (42) | 7 (12) |
| Siragusa [28]# | Prospective cohort | No, yes, yes, unclear, yes | Unclear | Recurrent DVT: extension of thrombus on CUS or venography Recurrent PE: new defect in V′/Q′ or CT lung scan, worsening of signs or symptoms, along with deterioration shown via chest radiograph, blood gases or ECG, or leg swelling with a positive CUS Major bleeding: according to ISTH criteria [30] Mortality: methods not described | 36 outpatients | 62 | 67/127 (53) | 36 (100) |
| Wells [29]# | RCT | Yes, yes, yes, yes, yes | Unclear | Recurrent DVT: extension of thrombus on CUS; in doubt serial testing or venography was used Recurrent PE: new defect on V′/Q′, angiography or CT lung scan according to PIOPED criteria. Patients who did not have high probability on V′/Q′ scan underwent further investigations (CUS leg, venography or angiography) Major bleeding: according to ISTH criteria [30] Mortality: methods not described; probably clinical records reviewed by independent committee | 90 outpatients | 58±17 | 273/505 (54) | 113/505 |
| Zondag [8] | Prospective cohort | Yes, yes, yes, yes, yes | Sent home from ED or within 24 h after admission | Recurrent VTE: new intraluminal filling defect on CT, pulmonary angiogram, V′/Q′, autopsy or extension of DVT on CUS Major bleeding: according to ISTH criteria [30] Mortality: clinical record or autopsy report reviewed by independent committee | 297 outpatients | 55±15 | 172 (58) | 28 (9) |
Data are presented as n, mean±sd or n (%), unless otherwise stated. ED: emergency department; VTE: venous thromboembolism; CT: computed tomography; V′/Q′: ventilation/perfusion ratio; DVT: deep vein thrombosis; CUS: compression ultrasonography; ISTH: International Society on Thrombosis and Haemostasis; RCT: randomised controlled trial; PE: pulmonary embolism; GP: general practitioner; TTE: transthoracic echocardiography; PIOPED: Prospective Investigation of Pulmonary Embolism Diagnosis. #: baseline characteristics (age, male sex, malignancies) described for a mixed group of patients with DVT and PE together, not reported separately for patients with PE; ¶: ambulatory care programme.