Interrupted Time Series Design

Interrupted time series designs are used to establish etiological and longitudinal effects

Interrupted time series designs are used to establish evidence of the relative effect of an intervention across multiple observations of an outcome.

There is only one treatment group in an interrupted time series design, and after random selection from the population, several preliminary observations of the outcome are taken from participants.

Then, the intervention is given to the group and several "post" observations of the outcome are recorded. 

One powerful aspect of interrupted time series designs are that participants serve as their own controls. This greatly increases the chances of detecting significant treatment effects.

​The etiology of disease states and longitudinal effects can be studied using interrupted times series designs. The stability of treatment effects can be closely monitored with the multiple post and maintenance observations of the outcome.
The interrupted time series design is a type of quasi-experimental design that establishes longitudinal effects across multiple observations pre- and post-treatment.
T = Treatment, M = Measurement of the outcome
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