55 A study undertaken by Reed 2004 looked at an evaluation o

55. A study undertaken by Reed (2004) looked at an evaluation of the effect of an intervention across medical care providers in an institution and at physician group practice level. The patient group were diabetics. Within the physician care group, there were a non-intervention group of patients and an in-tervention group. The following result was derived using the Pearson chi-square: 2 = 99.58, p = .0001 What does this suggest about the re-sult?

a. No difference between the groups

b. A significant difference between the groups and intervention effective

c. A significant difference between the groups and intervention not effective

d. None of the above 55a 56. In the following table, what number is missing?

Solution

The null hypothesis of a Chi-square test assumes that there is no dependence of two variables.

As the p-value is less than the significance level of 0.05, so we will reject the null hypothesis and conclude that there is significant difference between the groups and hence, intervention is effective.