Were all patients analyzed in the groups to which they were randomized?

Anything that happens after randomisation can affect the chance that a study patient has an outcome event. Therefore, we need to see if the investigators analysed the patients in the groups to which they were randomised, even if they crossed over to the other treatment group. This 'intention to treat' analysis preserves the value of randomisation.

An intention to treat analysis was done in the study that we identified. (This information was provided in the abstract available on Best Evidence.)

1. Was the assignment of patients to treatment randomized? And, was the randomization list concealed?
2. Was follow-up of patients sufficiently long and complete?
3. Were all patients analyzed in the groups to which they were randomized?
   
   And some less important points:
4. Were patients and clinicians kept blind to treatment?
5. Were groups treated equally, apart from the experimental therapy?
6. Were the groups similar at the start of the trial?