This paper reports psychometric evaluation of the Perceived Illness Experience Scale (PIE). This includes eight sub-scales developed to determine the impact of a chronic illness from the patient’s perspective. The sample included 34 patients (mean age = 17 years) successfully treated by limb salvage procedures for a primary bone tumour. Patients also completed measures of well-being (the SF-36) and function. To determine the relationship between patient and proxy ratings, mothers also completed the PIE. Evidence of construct validity of the PIE was obtained from significant correlations between PIE and SF-36 scale scores. There were also significant correlations between function and three of the eight sub-scales of PIE. Good correlations between patients’ and mothers’ ratings suggests that mothers can be useful proxy raters where patients are unable to provide data themselves. These data suggest that evaluations of patients following limb salvage surgery should not be limited to function measures alone, but need to include assessment of the perceived impact of treatment.