Contents
When to adjust for baseline covariates in randomized controlled trials?
This is rather unfortunate, as it means that trials of the same treatments, in the same population, will estimate (in expectation) different treatment effects if in their analyses they adjust for different baseline covariates.
Why are outcomes different in two randomized controlled trials?
As a consequence, differences in outcomes between the two groups can be attributed to the effect of being randomized to the treatment rather than the control (which often would be another treatment).
What makes a randomized controlled trial a gold standard?
Randomized controlled trials constitute what are generally considered to be the gold standard design for evaluating the effects of some intervention or treatment of interest.
Is there a way to adjust for covariates?
Recently methods have been developed for binary outcomes which allow adjustment for covariates which target the marginal odds ratio, allowing for improved precision and power for testing that this parameter is 1, overcoming the preceding issues.
How are long-term outcomes of randomised trials complicated?
However, analysis of long-term outcomes in randomised trials may be complicated by problems with the administration of treatment such as non-adherence, treatment switching and co-intervention, and problems obtaining outcome measurements arising from loss to follow-up and death of participants.
Can a trial have an unbiased treatment effect estimate?
Provided the randomization has not been compromised, the treatment effect estimate from trial is unbiased, even without adjusting for any baseline covariates. This is the case even when there appears to be an imbalance in respect of some baseline variable between the groups.
Can a count variable be treated as continuous?
Treating that count variable as continuous would give you predicted values that are non-integers, but perhaps that’s not a big issue in your particular data set. Q: How high does the count scale have to be before you can consider it continuous?