| Study |
Bias due to confounding |
Bias in selection of participants into the study |
Bias in classification of interventions |
Bias due to deviations from the intended intervention |
Bias due to missing data |
Bias in measurement of outcomes |
Bias in selection of the reported result |
Overall risk of bias |
| Judgement |
One or more prognostic variables are likely to be unbalanced between the compared groups. Essential characteristics, such as participants who underwent surgery during the hospitalisation, concomitant antiplatelet use, and history of venous thromboembolism, were not considered. The outcome was reported without any adjustment. |
Participants included in both groups were selected from a single hospital, and the first dose of anticoagulant was administered between 0 and 3 days after hospital admission. The start of follow‐up and start of intervention possibly did not coincide for most participants, and adjustment techniques to correct the presence of selection bias were not used. |
The intervention groups were clearly defined and recorded at the start of the intervention. Intervention status was probably not affected by knowledge of the outcome or the risk of the outcome. |
No deviations from the intended intervention were reported in the study, and if any deviation occurred from usual practice, it was unlikely to impact on the outcome. |
There were missing outcome data for 27 participants (1.9% of the total), balanced between the groups. These missing data would probably not have an important impact on the estimate. |
It is unlikely that the outcome assessment (objective outcome) was influenced by the knowledge of the intervention received by the study participants. |
The study protocol was not identified but all reported results corresponded to the intended outcome. |
The study is too problematic to provide useful evidence. |
