2 or 3 way ANOVA?


I'm not sure whether to use a 2 or 3 way ANOVA. My project I'm working on is focussing on one antibiotic and seeing how toxic it is at different concentrations and time points on bone cells obtained from different patients. I am aware there are 3 factors here, different patients, time points and concentration of antibiotic used.

However, my results are represented relative to the control experiment of each patient (cells in the absence of antibiotic). What I mean by this is say 100 cells from patient 6 were placed in 10mg of antibiotic and half were killed. In another experiment where a further 100 cells from patient 6 were also used but not placed in antibiotic, a quarter were found to be killed. My result would be expressed as 50/75 * 100 = 66.67% relative to control. ie the proportion of remaining live cells are represented as a percentage of the control experiment results. Now, I am wondering would different patients remain a factor and should a 2 or 3 way ANOVA be used. I would appreciate any help. Thanks.


TS Contributor
This appears to be a 1-way repeated measures ANOVA. Your factor is concentration and time makes it a repeated measures study. Patients would be replicates.