Alternately, you could use a repeated measures ANOVA to understand whether there was a difference in breaking speed in a car based on three different coloured tints of windscreen (e.g., breaking speed under four conditions: no tint, low tint, medium tint and dark tint). In this example, 'cigarette consumption' is your dependent variable, whilst your independent variable is 'time' (i.e., with three related groups, where each of the three time points is considered a 'related group'). This usually occurs in two situations: (1) when participants are measured multiple times to see changes to an intervention or (2) when participants are subjected to more than one condition/trial and the response to each of these conditions wants to be compared.įor example, you could use a repeated measures ANOVA to understand whether there is a difference in cigarette consumption amongst heavy smokers after a hypnotherapy programme (e.g., with three time points: cigarette consumption immediately before, 1 month after, and 6 months after the hypnotherapy programme). ANOVA with Repeated Measures using SPSS Statistics IntroductionĪn ANOVA with repeated measures is used to compare three or more group means where the participants are the same in each group.