How I assess comorbidities before hematopoietic cell transplantation.

The hematopoietic cell transplantation-comorbidity index (HCT-CI) is a comorbidity tool suited for recipients of HCT. The index has been shown to sensitively capture the prevalence and magnitude of severity of various organ impairments before HCT and to provide valuable prognostic information after HCT. Many investigators have validated the discriminative power of the HCT-CI, but others have not. One concern is the consistency in comorbidity coding across different evaluators, particularly in view of the relatively recent addition of the HCT-CI to the transplant evaluation process. In this article, comorbidity scoring was tested across different evaluators, and only a fair interobserver agreement rate could be detected. To address these issues, a brief training program is proposed here, consisting of systematic methodology for data acquisition and consistent guidelines for comorbidity coding that were summarized in a Web-based calculator. In a validation patient cohort, this training program was shown to improve the interevaluator agreement on HCT-CI scores to an excellent rate with weighted κ values in the range of 0.89 to 0.97. This proposed training program will facilitate reliable assessment of comorbidities in the clinic and for research studies leading to standardization of the use of comorbidities in prediction of HCT outcomes.