Development and validation of the Cerebral Performance Categories-Extended (CPC-E)

Abstract Background Optimizing resuscitation efforts after cardiac arrest (CA) requires valid and reliable measurements of functional outcomes. The Cerebral Performance Category (CPC), the historical “gold” standard outcome measure post-CA, lacks psychometric validation. The purpose of this study was to establish the psychometric properties of a revised CPC: the CPC-Extended (CPC-E). Methods The study had two phases: We established content validity of the CPC-E by identifying existing domains in the CPC, by adding new domains following a literature review, and iterative input from a panel of CA and rehabilitation experts. We tested the CPC-E's feasibility, intra-rater (IR) reliability and inter-rater reliability (IRR) using retrospective reviews of the electronic medical records (EMR) and “in-person” in-hospital administration. Results The CPC-E has 10 domains. For both IR and IRR record reviews, 5/10 domains had frequent missing data and in three instances, intraclass correlation coefficients (ICC) could not be calculated. Of the scores that could be calculated, ICC ranged from poor to high ( n = 30; 0.46–1.0) and poor to high ( n = 50; −0.16 to 0.93) for IR and IRR, respectively. No data were missing for the “in-person” IRR for the 10 domains and ICC ranged from good to excellent ( n = 26; 0.79–1.00). In-hospital and post-discharge domains were completed in under 7 min. Conclusions The CPC-E is a valid and clinically feasible outcome measure for describing post-CA impairment and disability status. In-person hospital administration of the CPC-E yields more complete data and good to excellent inter-rater reliability compared to retrospective EMR review.