Intended for healthcare professionals

Feature Data Briefing

Patient reported outcome measures: how are we feeling today?

BMJ 2012; 344 doi: https://doi.org/10.1136/bmj.d8191 (Published 11 January 2012) Cite this as: BMJ 2012;344:d8191

Re: Patient reported outcome measures: how are we feeling today?

An example of regression to the mean?

John Appleby's figure, a plot of preoperative score against "Health gain" (postoperative score-preoperative score) shows a tendency for better preoperative health to be associated with smaller health gains. Isn't this an example of regression to the mean [1] and so wouldn't a more preferable way of depicting any association be via a plot of postoperative score against the mean of both the preoperative and postoperative scores?
Perhaps Bland or Altman could comment!
[1] Bland JM, Altman DG. (1994) Some examples of regression towards the mean. 309, 780.
[2] Bland JM, Altman DG. (1986).Comparing methods of measurement: why plotting difference against standard method is misleading. Lancet, 346, 1085-7.

Competing interests: No competing interests

02 February 2012
Karla Hemming
Statistician
University of Birmingham
Edgbaston, Birmingham, B15 2TT