intention to treat analysis

Last reviewed 06/2020

Intention to treat analysis

  • when analysing a study it is important that all subjects who enter a study are accounted for - this is because failure to account for all subjects can bias the study results
    • consider the situation when some subjects assigned to the intervention of interest were withdrawn from a study due to adverse effects, and then were not included in the final analysis. In this scenario the withdrawn subjects could artificially inflate the response rate for the intervention
  • intention to treat analysis is method of overcoming this problem
    • all subjects who are assigned to an intervention at the start of the study are included in the analysis of that intervention group, whether or not they completed the study or received the intervention
    • this more closely represents the real life situation where some patients are not compliant with interventions


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