Purpose: This study aims to examine accuracy of CPS for 7-, 21-, and 42-day survival of inpatients with far-advanced cancer in 37 palliative care units in Japan, Korea, and Taiwan and its association with prognostic confidence.
Methods: In this study, discrimination of CPS was investigated through sensitivity, specificity, overall accuracy, and area under the receiver operating curves (AUROCs) according to 7-, 21-, and 42-day survival. The accuracies of CPS were compared with those of Performance Status-based Palliative Prognostic Index (PS-PPI) in three timeframe prediction. Clinicians were instructed to rate confidence level for each prediction on a 0–10-point scale.
Results: A total of 2,571 patients were analyzed. Among the three time-frames, the specificity was highest at 93.2–100.0% for the 7-day CPS and sensitivity was highest at 71.5–86.8% for the 42-day CPS. The AUROCs of the 7-day CPS were 0.88, 0.94, and 0.89 while those of PS-PPI were 0.77, 0.69, and 0.69 for JP, KR, and TW, respectively. In all timeframe, CPS was more accurate than the PS-PPI. As for 42-day prediction, sensitivities of PS-PPI were higher than those of CPS. Clinicians’ confidence was strongly associated with the accuracy of prediction in all three countries (all p values <0.01).
Conclusions: CPS accuracies were highest (0.88 -0.94) for the 7-day survival prediction. CPS was more accurate than PS-PPI in all timeframe prediction. Meanwhile, PS-PPI can be a screening tool in 42-day survival prediction which may be supplementary to CPS. Prognostic confidence was significantly associated with the accuracy of CPS.