Caution in interpretation neededBMJ 1995; 310 doi: https://doi.org/10.1136/bmj.310.6980.667 (Published 11 March 1995) Cite this as: BMJ 1995;310:667
- Stephen Senn,
- Rajesh Bakshi,
- Nathalie Ezzet
- Biometrician Central medical adviser Biometrician Medical Department, Ciba-Geigy AG, Basle CH-4002, Switzerland
EDITOR,—Considerable caution must be exercised in interpreting the results of Lyn March and colleagues' n of 1 trials in osteoarthritis.1 For example, the authors observe that “seven of he eight patients who changed treatment from baseline changed to paracetamol (P=0.07, exact binomial).” Of the 20 patients analysed, 16 were taking a non-steroidal anti-inflammatory drug and only three were taking paracetamol. Therefore, at most three patients could have changed their treatment from paracetamol.
Furthermore, the authors implicitly assume that failure to find …