Article Text

Download PDFPDF
Deciding on progression of joint damage in paired films of individual patients: smallest detectable difference or change


Progression of radiological joint damage is usually based on the simultaneous assessment of a series of films from an individual patient (“paired”, with or without known sequence). In this setting the degree of progression that can be reliably detected above the measurement error is best determined by the smallest detectable change, and overestimated by the traditionally calculated smallest detectable difference. This knowledge is important for calculation of the proportion of patients showing radiographic progression in clinical trials.

  • ANOVA, analysis of variance
  • SDC, smallest detectable change
  • SDD, smallest detectable difference
  • joint damage progression
  • rheumatoid arthritis

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.