Atreatment group mean = 12.2; non-treatment group mean = 16.2
mean difference 4
b) trial 1 mean 14, difference 1.8 above & 2.2 below
trial 2 mean 14.8, difference 2.6 above & 1.4 below
trial 3 mean 14.2, difference 2 above & 2 below
trial 4 mean 14.8, difference 2.6 above & 1.4 below
c)There is not a significant difference in the number of days between surgery and returning to work with the trial data that was chosen.
Them number of days were close together. The range was less than 3 days difference.