In: Math
A study was performed comparing the efficacy of a new pain reliever, Galproxidone, to several pain relievers commonly prescribed after orthopedic surgury. Patients were asked to rate their pain after taking each medication. The data is listed below. Perform an ANOVA to determine the relative efficacy of Galproxidone on pain relief compared to the other pain relievers. If differences exist, perform a Bonferoni post-hoc test to determine which pain relievers are different from Galproxidone. Interpret the final results in terms of relative efficacy of the pain relievers.
Acetaminophen |
Oxycodone |
Hydroxycodone |
Galproxidone |
5 |
2 |
3 |
2 |
5 |
2 |
4 |
3 |
5 |
1 |
5 |
5 |
6 |
2 |
3 |
2 |
6 |
3 |
3 |
1 |
4 |
1 |
4 |
1 |
4 |
3 |
3 |
3 |
4 |
2 |
4 |
5 |
4 |
2 |
2 |
2 |
5 |
1 |
2 |
1 |
From ANOVA table we see that p-value<0.05 so hence mean effects of pain relievers are not all same. Hence we perform Bonferoni post-hoc test to determine which pain relievers are different from Galproxidone.
Since here we compare three mean differences i.e. Acetaminophen -Galproxidone, Oxycodone -Galproxidone, Hydroxycodone -Galproxidone, so Bonferroni correction=0.05/3= 0.0167. For this set of 3 tests, you would reject the null only if your p-value was smaller than 0.0167.