Observer variability in recording the peripheral pulses.

Examination of the leg and foot pulses is indi- spensable in the assessment of the patient with sus- pected peripheral arterial disease, so it is important to know how much weight to attach to the findings. The topic of observer variability is of increasing interest in clinical medicine, while population studies can only be of use if methods are repro- ducible, that is provide "the same results on the same subject on two or more occasions, in the hands either of the same or of more than one observer, the subject of the test being in the same state of health or disease" (Fletcher and Oldham, 1964). A previous study of observer variability in recording pulses in the foot gave results from which the authors concluded that there was "very great observer error with respect to the detection of ankle pulses", and that "the inability to detect an ankle pulse by one observer is quite without significance" (Ludbrook, Clarke, and McKenzie, 1962). These are disturbing suggestions for the clinician and the epidemiologist, particularly in view of the consider- able attention currently being paid to the detection of early peripheral arteriosclerosis (Widmer, Green- sher, and Kannel, 1964; Cooper, Hill, and Edwards, 1967; Lancet, 1967).