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Feb 6, 2017  04:02 PM | Alice Yo
Problem implementing study design
Dear Alfonso and CONN experts
I have encountered a problem implementing my study design in CONN and appreciate your help. 

I have 2 groups of subjects. Group 1 has 4 different sessions (s1, s2, s3, s4) and group 2 has the same 4 sessions but for 2 different time points (s1_t1, s1_t2, s2_t1, s2_t2…).
I want to compare each of the 4 sessions (e.g. s1) of group1 with the corresponding session of group2 at the 2 different time points (that is, to compare s1 with s1_t1 and also to compare s1 with s1_t2), and also for group 2 to compare each session between the 2 different time points (e.g. s1_t1 vs. s1_t2).
To do this, I have uploaded 4 sessions for group 1 and 8 sessions for group 2 (that is the 4 sessions at the 2 different time points) and defined 8 conditions.

Now I have a problem with mapping the 4 sessions of group 1 into the 8 conditions. If I only map them into 4 conditions (and allow missing data), in the group analysis I can’t compare these sessions to both time points of group 2.
I tried to map the 4 sessions into the 8 conditions by mapping each session into 2 conditions (I thought this should work!), but still in the group analysis only 4 conditions seem to have data for group 1, even though according to the settings the other 4 conditions should have the same identical data as the first four. So again I can't compare the sessions of group 1 to both time points of group 2.

I would highly appreciate any help on this.
Many thanks
Feb 7, 2017  02:02 PM | Alfonso Nieto-Castanon - Boston University
RE: Problem implementing study design
Dear Alice,

I would simply define 8 conditions for both subject-groups (as you mention by mapping each session into 2 conditions for group1 subjects). If you have already tried this and you are not seeing the 8 conditions in the second-level results tab that probably means you need to re-run some previous step(s) in order for the new condition info to propagate all the way from Setup to Results.

Hope this helps
Alfonso 
Originally posted by Alice Yo:
Dear Alfonso and CONN experts
I have encountered a problem implementing my study design in CONN and appreciate your help. 

I have 2 groups of subjects. Group 1 has 4 different sessions (s1, s2, s3, s4) and group 2 has the same 4 sessions but for 2 different time points (s1_t1, s1_t2, s2_t1, s2_t2…).
I want to compare each of the 4 sessions (e.g. s1) of group1 with the corresponding session of group2 at the 2 different time points (that is, to compare s1 with s1_t1 and also to compare s1 with s1_t2), and also for group 2 to compare each session between the 2 different time points (e.g. s1_t1 vs. s1_t2).
To do this, I have uploaded 4 sessions for group 1 and 8 sessions for group 2 (that is the 4 sessions at the 2 different time points) and defined 8 conditions.

Now I have a problem with mapping the 4 sessions of group 1 into the 8 conditions. If I only map them into 4 conditions (and allow missing data), in the group analysis I can’t compare these sessions to both time points of group 2.
I tried to map the 4 sessions into the 8 conditions by mapping each session into 2 conditions (I thought this should work!), but still in the group analysis only 4 conditions seem to have data for group 1, even though according to the settings the other 4 conditions should have the same identical data as the first four. So again I can't compare the sessions of group 1 to both time points of group 2.

I would highly appreciate any help on this.
Many thanks
Feb 13, 2017  10:02 AM | Alice Yo
RE: Problem implementing study design
Thank you, this worked!