Interconversion of three measures of performance status: an empirical analysis.

PURPOSE: To construct empirically a conversion table to convert performance status scores among the Eastern Cooperative Oncology Group (ECOG), Karnofsky Performance Status (KPS) and Palliative Performance Scale (PPS) measures, using a large sample of patients with advanced cancer. METHODS: Seven physicians completed assessments on 1385 consecutive patients attending an oncology palliative care clinic, or admitted to an acute cancer palliative care unit. The three measures were distributed as a questionnaire package; the order in which they were presented was randomly assigned for each week. Scales were compared using the hit rate and the weighted kappa coefficient (κ(w)). The KPS and PPS were compared directly; for comparisons of either scale with the ECOG, all 70 possible categorisations of KPS and PPS were computed. An 'ideal' categorisation was selected based on maximisation of both statistical methods. RESULTS: The KPS and PPS matched in 1209 out of 1385 assessments (hit rate 87%; κ(w) 0.97). For both the KPS and the PPS, the categorisation of 100 (ECOG 0), 80-90 (1), 60-70 (2), 40-50 (3), 10-30 (4) had the highest hit rate (75%), and the second highest κ(w) (0.84, p<0.0001). One other combination had a slightly higher κ(w) (0.85 for both KPS and PPS), but a lower hit rate (73% for KPS, 72% for PPS). CONCLUSIONS: We have derived empirically a conversion scale among the ECOG, KPS and PPS scales. The proposed scale provides a means of translating amongst these measures, which may improve accuracy of communication about performance status amongst oncology clinicians and researchers.

Nurse and physician inter-rater agreement of three performance status measures in palliative care outpatients.

INTRODUCTION: Performance status (PS) scales are used widely in oncology practice and research. We compared inter-rater agreement, between nurses and physicians, for three commonly used PS scales. MATERIALS AND METHODS: Patients attending an oncology palliative care clinic were assessed by a physician and nurse who blindly completed Eastern Cooperative Oncology Group (ECOG), Karnofsky PS (KPS), and palliative PS (PPS) scales. Patients completed the Edmonton symptom assessment system (ESAS). RESULTS: Inter-rater agreement (weighted kappa) for the 457 patients was 0.67 for the ECOG, 0.74 for the KPS, and 0.72 for the PPS. There was no difference between proportions of physicians' vs. nurses' ratings of KPS, >60 vs.