In the Exit Ticket of a previous lesson, an experiment with 20 subjects investigating a new pain reliever was introduced.
The subjects were asked to communicate their level of pain on a scale of 0 to 10 where 0 means no pain and 10 means
worst pain. Due to the structure of the scale, a patient would desire a lower value on this scale after treatment for pain.
The value “ChangeinScore” was recorded as the subject’s pain score after treatment minus the subject’s pain score
before treatment. Since the expectation is that the treatment would lower a patient’s pain score, a negative value
would be desired for “ChangeinScore.” For example, a “ChangeinScore” value of -2 would mean that the patient was in
less pain (for example, now at a 6, formerly at an 8).
In the experiment, the null hypothesis would be that the treatment had no effect. The average change in pain score for
the treatment group would be the same as the average change in pain score for the placebo (control) group.