Another report by Kraaijenhagen found the opposite finding. Further the two latest reports are also conflicting. Samana reports a higher rate of travel in those with DVT (Odds ratio: 2.35 (1.45-3.8)) compared to those without DVT, while Arya reports an odds ratio of 1.3 (0.6-2.8).

See: Kraaijenhagen RA, Haverkamp D, Koopman MMW, Prandoni P, Piovelta F, Buller HR. Travel and risk of venous thrombosis. Lancet 356:1492-93, 2000.

Samama MM. An epidemiologic study of risk factors for DVT in medical outpatients; the Sirius study. Arch Int Med 160:3415-20, 2000.

Arya R, Barnes JA, Hossain U, Patel RK, Cohen AT. Long-haul flights and deep vein thrombosis: a significant risk only when additional factors are also present. Brit J Haematology 116:653-54, 2002.