Question: Dr. McGill had several patients experiencing difficulties sleeping and requested a medication. Dr. McGill reviewed the literature and found a study on two experimental sleeping pill medications that he thought may be useful for his patients. The study is summarized as follows:

? In a study of two experimental soporific (sleeping pill) medications, a doctor at a sleep clinic randomly selected 10 insomniacs from among her patients.

? Prior to the intervention, the doctor collected baseline data on the number of hours of sleep that each patient got each night. Medication one, dextro hyoscyamine hydrobromide, was then administered for one week and each patient’s average extra sleep per night, in hours, was calculated and recorded.

? A negative value indicated that the patient got less sleep when using that medication.

? A week passed in which the patients were given no medication, to clear their systems of the effects of medication one.

? The patients were then administered medication two, laevo hyoscyamine hydrobromide, for one week, and their average extra sleep per night, in hours, was calculated and recorded. The results from the ten patients are presented in the Table below:

Extra sleep, in hours, for 10 patients under two different medications
Patient Medication 1 Medication 2
1 0.7 1.9
2 -1.6 0.8
3 -0.2 1.1
4 -1.2 0.1
5 -1.0 -0.1
6 3.4 4.4
7 3.7 5.5
8 0.8 1.6
9 0.0 4.6
10 2.0 3.4
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