A pharmaceutical company tested four formulations of a painrelief medicine for migraine headache sufferers. For theexperiment, 32 volunteers were selected and 8 were randomlyassigned to one of four drug formulations. The subjects wereinstructed to take the drug during their next migraine headacheepisode and to report the time it needs for their pain to go awayafter taking the drug. Carry out an appropriate test to see ifthere are any mean differences in pain relief time (in minutes)among the four drug formulations. Calculate the mean squares fortreatments (MST), the mean squares for error(MSE), and the value of the test statistic (or theF-ratio). The ANOVA table is listed below.
Analysis of Variance
Source | Sum-of-Squares | df | Mean-Square | F-ratio | P-value |
drug formulation | 18.2222 | 3 | | | 0.0028 |
Error | | 28 | | | |
Total | 46.6666 | | | | |
