Choosing a statisticBMJ 2009; 339 doi: https://doi.org/10.1136/bmj.b2702 (Published 08 July 2009) Cite this as: BMJ 2009;339:b2702
- John Fletcher, clinical epidemiologist
- 1BMJ, BMA House, Tavistock Square, London WC1H 9JR
Which statistical test is best for each outcome measure?
a) Comparing improvement in pain scores over 4 weeks using a visual analogue scale in a trial of 100 people with back pain.
b) Comparing the effect of two drugs on time to reduce fever below 38ºC in two groups of 100 febrile infants.
c) Comparing for 100 countries the number of doctors trained per million population with the infant mortality rate of that country.
d) Comparing death rates at 30 days after discharge from hospital of 100 patients having hip surgery and 100 patients having eye surgery.
e) Chi square test (χ2) …