Repeated measures ANOVA vs. Independent one-way

#1
This is a scenario from a paper in 2nd review. The authors used a one-way anova with obvious dependent measures. For example, if they had 100 participants, and if they were measuring say calories expended, then they observed calories expended while participants (for example) engaged in activity A, activity B, and activity C. AND, observed under those 3 activities under two different conditions (X and Y). So their one-way anova had a sample size (say) of 600. All the makings for a two-way repeated measures anova. Which was my comment on review #1. The authors are however sticking to their guns. And they gave no argument. Their paper is excellent otherwise. So I'm wondering if this could get through somehow as is. Despite the breach of independent observations. The X and Y conditions were assessed on different days. But the A, B, and C conditions were observed all at once. In other words, they engaged in one main task during the X and Y conditions, and observations were able to tease apart calorie expenditure in conditions A, B, and C.
 

j58

Active Member
#2
If I were a reviewer, I would wonder why the authors insist on what appears on its face to be an inappropriate analysis. In particular, I would be worried that they conducted the apropriate analysis, and it didn't show what they hoped it would.

That said, If, in a 2-way repeated measures analysis, it was found that neither the activity factor, the interaction with the treatment condition, nor the subject (block) effect were significant, in principle, one could drop those factors from the model, and use 1-way ANOVA instead. However, it is the authors' responsibilty to demonstrate this. If they refuse to do so and cannot convincingly justify their analysis, I would recommend that the journal reject the paper.
 
#3
Thank you j58. I agree. I didn't necessarily think they ran the repeated measures option. The way the paper read, I felt maybe it was the result of a recent dissertation. And maybe they wanted to stay in sync with that. Anyway...nice to have another opinion on this. I'll stick to my guns too.