Was patient assignment randomized, and the randomization process “concealed”?

Were all patients who entered the trial accounted for?

Was follow-up adequate? Were patients analyzed according to the “intention to treat” principle?

Were study personnel “blinded” to treatment?

Were the patient groups similar before treatment?

Apart from the experimental intervention, were the groups treated equally?

How large was the treatment effect?

How precise was the estimate of the treatment effect?

Were the study patients similar to my patients?

Were the measured outcomes clinically relevant?

Are my surgical skills similar to those of the study surgeons?