Hi, I was wondering if anyone can help me. I have to compare data taken from a food intake study carried out in 2 strains of mice following injections of a vehicle, and 3 other anorexigenic peptides. Food intake data was recorded at two different time points. What I need to do is see if 1: strains respond differently 2: If the two time points are different and 3: compare it all to the control. I have tried two way ANOVA on GraphPad prism 5 however, I am not sure if its correct or which one to use. Can somebody guide me at all? thanks

hey, I don't use that software - but it sounds like a 3 way ANOVA to me;
1) repeated measures - Time (time 1 before/time 2 after)
2) between measures - Strain ( type 1/type 2)
3) between measures - Injection type (control, 1,2,3,4,)
in SPSS you would start off choosing Repeated measures ANOVA, and then put in Strain and Injection type in as Between measures variables so it may be similar on your software perhaps :)

Thanks for that. GraphPad unfortunately doesn't have a three-way option, but I may have a go in spss, cheers! :)