Analysis methods: how the trial data will be analysed

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  •  What does it mean?
When patients enter a trial, we collect their information. We usually collect their information at baseline (who is taking part in the trial?), and during follow-up (with questionnaires and/or clinical visits). This information is gathered in a database and analysed to answer the ultimate trial question - does the treatment work when compared with a control (usually another treatment)? 

Trial analysis is complex and involves statistical models that estimate the treatment effect, ie how well the treatment works when compared with a control. 

The statistical models we use to analyse trial data may be "adjusted for" patient's characteristics. This usually happens if we believe those characteristics are important to understand the treatment effect. Statistical models make assumptions about the information collected and it is important to know those assumptions in order to interpret the findings of the trial correctly.
  • An example
In the toothpaste trial, we might consider people's age, their toothpaste preference, and their socioeconomic status help predict how well the treatment works. If that is the case, we will include those characteristics in the statistical model. 
  • How can patients be involved?
When treatment claims depend on assumptions, it is important to consider the basis for the assumptions and to test how sensitive the results are to changes in the assumptions.

You can find more examples and information about how assumptions affect the interpretation of treatment claims here.

Comments

  1. Unknown11 March 2022 at 07:12

    You say a treatment is compared to another treatment. Does a placebo count as 'another treatment'? People I know who have been involved in clinical trials are very aware they may be given the trial drug or a placebo. I have never heard anyone talk about one treatment or aother.

    It is important to include public and patients in discussion about assumptions. I would definitely have something to say about assumtions in the toothpaste trial.

    ReplyDelete

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