Skip to main content
Cross Validated

Return to Question

Minor textual edits.
Source Link
Thomas Bilach
Thomas Bilach
  • 6.5k
  • 2
  • 13
  • 33

Difference in differences-in-differences with two treatments

I have two groups. 

Group 1 received intervention A and Group 2 received intervention B. I'm interested in seeing if intervention A is more effective than intervention B. People cannot be enrolled in both interventions at the same time. 

Am I able to use difference in differences-in-differences to compare the two interventions, or would I need to include a third group where the people receive no intervention (control group)? What I have are the dates in which someone enrolled in their respective intervention and the pre-enrollment and post-enrollment outcomes. The outcome was measured every 3-6 months pre-enrollment and every 3-6 months post-enrollment.

Also, since people can enroll in any of the interventions at different times, I would like to standardize the time dimension as the number of days before and after enrollment into the intervention. If I were to include a third group, how would I standardize the time since there is no enrollment?

Difference in differences with two treatments

I have two groups. Group 1 received intervention A and Group 2 received intervention B. I'm interested in seeing if intervention A is more effective than intervention B. People cannot be enrolled in both interventions at the same time. Am I able to use difference in differences to compare the two interventions, or would I need to include a third group where the people receive no intervention (control group)? What I have are the dates in which someone enrolled in their respective intervention and the pre-enrollment and post-enrollment outcomes. The outcome was measured every 3-6 months pre-enrollment and every 3-6 months post-enrollment.

Also, since people can enroll in any of the interventions at different times, I would like to standardize the time as the number of days before and after enrollment into the intervention. If I were to include a third group, how would I standardize the time since there is no enrollment?

Difference-in-differences with two treatments

I have two groups. 

Group 1 received intervention A and Group 2 received intervention B. I'm interested in seeing if intervention A is more effective than intervention B. People cannot be enrolled in both interventions at the same time. 

Am I able to use difference-in-differences to compare the two interventions, or would I need to include a third group where the people receive no intervention (control group)? What I have are the dates in which someone enrolled in their respective intervention and the pre-enrollment and post-enrollment outcomes. The outcome was measured every 3-6 months pre-enrollment and every 3-6 months post-enrollment.

Also, since people can enroll in any of the interventions at different times, I would like to standardize the time dimension as the number of days before and after enrollment into the intervention. If I were to include a third group, how would I standardize time since there is no enrollment?

Source Link
waterdesk91
waterdesk91
  • 23
  • 3

Difference in differences with two treatments

I have two groups. Group 1 received intervention A and Group 2 received intervention B. I'm interested in seeing if intervention A is more effective than intervention B. People cannot be enrolled in both interventions at the same time. Am I able to use difference in differences to compare the two interventions, or would I need to include a third group where the people receive no intervention (control group)? What I have are the dates in which someone enrolled in their respective intervention and the pre-enrollment and post-enrollment outcomes. The outcome was measured every 3-6 months pre-enrollment and every 3-6 months post-enrollment.

Also, since people can enroll in any of the interventions at different times, I would like to standardize the time as the number of days before and after enrollment into the intervention. If I were to include a third group, how would I standardize the time since there is no enrollment?