A psychologist is interested in determining whether a new online pain management program improves (reduces) pain scores for its participants. A group of pain patients are randomly assigned to participate in either the online program or a control group. At the end of the study the researcher administered a widely used pain level scale ranging from 1-10. What is the null hypothesis for the study?

The available options are:

a. The percentage of treatment and control group participants with significant pain is the same in the population

b. The treatment group mean equals 1 in the population, and the control group mean is greater than 1 in the population

c. Both population means equal 1

d. The difference between the treatment and control group means is zero in the population

e. The difference between the sample means of the treatment and control group is zero

D. The difference between the treatment and control group means is zero in the population

Explanation:

Considering the fact a Null Hypothesis is a form of conventional statistical theory that proposes that there is zero or no statistical relationship and significance in a group of assigned single observed variables, between two groups of experimental data and assessed events.

In this case, the NULL HYPOTHESIS is the zero difference between the treatment or online group and the control group means in the population