title: The validity, reliability, reproducibility and extended utility of ankle to brachial pressure index in current vascular surgical practice.
abstract: BACKGROUND
  Despite the increasing sophistication of vascular surgical practice, more than three decades after its introduction to clinical practice, the ankle to brachial pressure index (ABPI) remains the cornerstone of non-invasive assessment of the patient with symptomatic peripheral arterial disease (PAD).
  
  
  OBJECTIVE
  To summarise what is known about ABPI and critically appraise its validity, reliability, reproducibility and extended utility.
  
  
  METHODS
  A MEDLINE (1966-2004) and Cochrane library search for articles relating to measurement of ABPI was undertaken; see text for further details.
  
  
  RESULTS
  There is considerable disagreement as to how ABPI should be measured. Furthermore, various factors, including the type of equipment used, and the experience of the operator, can result in significant inter- and intra-observer error. As such, care must be taken when interpreting data in the literature. ABPI is valuable in the assessment of patients with atypical symptoms, venous leg ulcers and after vascular and endovascular interventions. However, absolute pressures are probably more valuable in patients with critical limb ischaemia. ABPI is also useful in subjects with asymptomatic PAD where it correlates well with, and may be used in screening studies to quantify, cardiovascular risk.
  
  
  CONCLUSIONS
  While its apparent simplicity can beguile the unwary, ABPI will continue to have a key role in the assessment of symptomatic PAD. ABPI is also likely to have extended utility in health screening and institution of best medical therapy in asymptomatic subjects.
authors.affiliation: University Department of Vascular Surgery, Birmingham Heartlands Hospital, Birmingham, UK.
authors.forename: M F
authors.initials: MF
authors.lastname: Caruana
authors.forename: A W
authors.initials: AW
authors.lastname: Bradbury
authors.forename: D J
authors.initials: DJ
authors.lastname: Adam
mesh_terms: D000842:Ankle / Q000098:blood supply*; D001794:Blood Pressure; D001916:Brachial Artery / Q000503:physiopathology*; D006801:Humans; D016491:Peripheral Vascular Diseases / Q000503:physiopathology* / Q000601:surgery; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D014656:Vascular Surgical Procedures