Table 1 Exclusion criteria

No living human subjects

e.g. mice model

Focus on wrong procedure

e.g. unicompartmental knee replace-ment

Focus on risk factors for other complications

e.g. limb swelling

Focus on other thrombo-related factors

e.g. bleeding or blood transfusion

Focus on fat embolism

e.g. fat embolism after femoral head resection

Have not mentioned any risk factor

e.g. prevelance studied alone

Not primary clinical research

e.g. literature review or guidline

Level III prognostic study

e.g. case–control

Level IV prognostic study

e.g. case series

Level V prognostic study

e.g. expert opinion

Diagnostic study

e.g. spiral CT for the detection of pulmonary embolism

Economic and decision analyses

e.g. cost-effectiveness of extended-duration thromboprophylaxis after THA

Indispensable data missing or not available

e.g. no p-value

Article could not be retrieved

e.g. not available in electronic or print archives

Duplicate publication

e.g. Similar title, sample size ,and outcome data