Additional analyses to answer different questions

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  •  What does this mean?
In trial analysis we are interested in understanding how well a treatment works. However, as the trial journey evolves and becomes more complex, this question can also be more complicated than what it looks. For example, we might be interested in understanding whether the treatment works for all patients regardless of whether they take it as instructed, or whether the treatment works in patients that tolerate the treatment.

  • An example
When Emma developed mouth ulcers after three months of using toothpaste A, she decided to stop using the toothpaste. In this case, Emma was no longer adhering to the treatment after three months because she was not using it at all. A decision needs to be made about whether Emma is included in the final analysis of the trial or not. This will depend on the question - are we interested in knowing how well toothpaste A works compared with toothpaste B irrespective of whether patients took the treatment? Or are we interested in knowing how well toothpaste A works compared with B for patients that tolerated the toothpastes well?

  • How can patients be involved?
Patients can be involved in defining the main trial question, but also any additional questions the trial should answer to make it useful in a clinical context. Additional questions should be discussed at the start of the trial (design or protocol) and should be limited to a few, key questions.

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