| McKenzie AR et al, 2000, Scotland | 20 consecutive IDUs presenting with iliofemoral DVT. LMWH given for median of seven weeks | Cohort, retrospective case reports | Incidence of recurrent DVT after three months. Incidence of symptomatic PE | 8 patients asymptomatic, 7 persistent DVT (1 declined treatment), 5 lost to follow up. None with PE after starting treatment. | Very small number of patients. Retrospective |
| Lawson WL et al, 2003, Scotland | 130 IDUs over 1 year presenting with DVT. 98% had at least one dose of LMWH | Cohort, retrospective audit | Incidence of recurrent DVT and symptomatic PE | Low rate of symptomatic PE | Small number of patients Retrospective |