title: Claudication distance is poorly estimated and inappropriately measured.
abstract: BACKGROUND
  Claudication distance is the commonest measure of the disability caused by lower-limb occlusive arterial disease. The accuracy of claudication distance as a surrogate for handicap has been assessed.
  
  
  METHODS
  Seventy patients who attended a specialist vascular clinic with intermittent claudication were studied prospectively. Patients were asked to estimate their claudication distance and maximum walking distance before undergoing both a patient-controlled corridor walk and a fixed-speed treadmill walk.
  
  
  RESULTS
  The claudication distance reported by patients bore little relation to the distance recorded in the medical correspondence. There was no correlation between the estimated distance and the actual distance walked on either a patient-controlled corridor walk or a fixed-speed treadmill walk. Most patients were able to walk substantially further at their own speed on the corridor than on the treadmill at a slower speed.
  
  
  CONCLUSIONS
  Claudication distance is spuriously estimated, inaccurately reported, falsely recorded, inappropriately measured and usually misinterpreted. It is of little value in judging the need for treatment. Objective measures of the handicap caused by the disability of reduced walking distance are required if rational management decisions are to be made.
authors.affiliation: University of Oxford, Nuffield Department of Surgery, John Radcliffe Hospital, UK.
authors.forename: C J
authors.initials: CJ
authors.lastname: Watson
authors.forename: D
authors.initials: D
authors.lastname: Phillips
authors.forename: L
authors.initials: L
authors.lastname: Hands
authors.forename: J
authors.initials: J
authors.lastname: Collin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004185:Disability Evaluation; D006233:Persons with Disabilities; D005080:Exercise Test; D005260:Female; D006801:Humans; D007383:Intermittent Claudication / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D016138:Walking / Q000502:physiology*