I have conducted an experimental design on exploring the effectiveness of mindfulness skills on students' psychological wellbeing. I aim to test if there is a significant change on students' levels of depression ,anxiety, emotion regualtion and mindfulness skills, depending on the intervention they have received.
The control group received no intervention and the intervention group trained and practiced mindfulness for 21 days. I test my sample twice, pre-intervention (to get a baseline) and post intervention (one group have received the intervention whereas other group is not received but tested).
In this case, I am confused if I need to use time as independent variable or not. Which ANOVA would work best ?
MAny thanks in advance.
There is an excellent paper by Frison and Pocock that you should read:
Article Repeated measures in clinical trials: Analysis using mean su...
They state " Analysis of covariance is the method of choice and its superiority over analysis of post‐treatment means or analysis of mean changes is quantified, as regards both reduced variance and avoidance of bias, using a simple model for the covariance structure between time points." and I wouldn't dream of arguing with that.
Hello Simge,
The same conclusion offered by Ronán Michael Conroy was explicated in a short text edited by Chester Harris (1963), Problems in the Measurement of Change: https://journals.sagepub.com/doi/abs/10.1177/001316446402400333?journalCode=epma
Good luck with your work.
- Badges
- Science topic