What does 'repeated measures' mean? How is it different than 'randomized block'? If you measure response to three different drugs at two time points with subjects from two age ranges, then you have three factors: drug, time and age so wouldwant to choose three-way ANOVA. For example, you might measure a response to three different drugs at two time points. Two-way ANOVA, also called two-factor ANOVA, determines how a continuous response is affected by two factors. Enter your data into a contingency table and analyze with a chi-square test. The dependent variable has two possible outcomes. This may or may not be a reasonable assumption for your situation I want to compare three groups. It cannot test for interaction without replicates, so simply assumes there is none. In this case, Prism will only be able to compute ordinary (not repeated measures) ANOVA, and will assume that there is no interaction between the row and column factor.
Yes, two-way ANOVA is possible if you only have one value for each condition (no subcolumns). I only know the group means, and don't have the raw data and don't know their SD or SEM. It is not possible to compute repeated measures ANOVA without access to the raw data. You can enter data as mean, SD (or SEM) and n, and Prism can compute two-way ANOVA. I know the mean, SD (or SEM) and sample size for each group.