Development of the Pediatric Neuro-Oncology Rating of Treatment Intensity (PNORTI).

Measures of treatment intensity for childhood cancer are needed in research in order to control for variability in treatments. Existing measures of treatment intensity for childhood cancers do not reflect the complexities of treatment protocols for central nervous system (CNS) tumors. This paper describes the development of the Pediatric Neuro-Oncology Rating of Treatment Intensity (PNORTI). PNORTI development occurred in three phases. Phase 1: five experts in pediatric neuro-oncology created a 5-point scale of treatment intensity and 42 pediatric neuro-oncology providers completed a three-part online questionnaire to evaluate the classification system and apply the rating system to 16 sample patients. Validity was determined by respondents classifying therapy modalities into intensity levels. Inter-rater reliability was calculated from ratings of the 16 sample patients. Phase 2: three experts revised the PNORTI based on survey results and 18 pediatric neuro-oncology providers evaluated the classification system. Phase 3: ten experts in pediatric neuro-oncology refined and finalized the PNORTI and rated 10 sample patients using the PNORTI. Agreement between median ratings of the survey respondents and criterion raters for chemotherapy intensity (r's = .82 and 1.0) and overall treatment intensity level (r's = .91 and .94) were high in Phases 1 and 2. Inter-rater reliability also was very high when using the PNORTI to classify the 16 sample patients in Phase 1 (median agreement of r = .93 and rICC = .99) and the 10 sample patients in Phase 3 (median agreement of r = .92 and rICC = .98). The PNORTI is a valid and reliable method for classifying the intensity of different treatment modalities used in pediatric neuro-oncology.