The Results section of the paper contined the following table:
| Variable | Wet (intervention) (n=450) | Dry (control) (n=420) | P value |
|---|---|---|---|
| Mean (SD) age (years) | 55.9 (16.6) | 56.5 (16.2) | 0.58 |
| Male patients | 249 (55) | 208 (50) | 0.08 |
| Mean (SD) days to removal of sutures | 8.6 (2.2) | 8.6 (2.2) | 1 |
| Presence of diabetes | 9 (2) | 14 (3) | 0.2 |
| History of other medical condition* | 8 (2) | 10 (2) | 0.5 |
| Treated with 1% lignocaine adrenaline | 435 (97) | 411 (98) | 0.3 |
| Excision of skin cancer | 294 (65) | 289 (69) | 0.3 |
| Excision at lower limb | 112 (25) | 106 (25) | 1 |
| * Chronic obstructive pulmonary disease (n=8), anaemia (1), "aspirin" (2), "steroids" (3), "warfarin" (2), ischaemic heart disease (1), and peripheral vascular disease (1). | |||
Question 1: What null hypothesis are these tests testing?
Each of these tests is testing the null hypothesis that the means or proportions are the same in the two populations from which the treatment groups come.
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Last updated: 31 July, 2006.