title: Quantitative tool to evaluate the somatic burden due to chemotherapy-induced adverse events: the somatic burden score.
abstract: OBJECTIVE
  Although there are several established methods like the Common Terminology Criteria for Adverse Events (CTCAE), heretofore, no objective, quantitative measurement exists for the somatic burden due to chemotherapy-induced adverse events (SB-CHINAE). We developed the Somatic Burden Score (SBS-AE) that combines the severity grade and duration of an AE. This paper describes the development and validation of the SBS-AE.
  
  
  METHODS
  SBS-AE's calculation was based on the number of days of CTCAE grades of a particular AE. The target value was the weighted, relative duration of an AE grade using CTCAE v3.0. We applied the SBS-AE in 64 patients with hematological malignancies and high-dose chemotherapy (HDC). The ratio measurement scale of the SBS-AE allows all statistical measures using SBS-AE, as all necessary mathematical operations are defined for it. We calculated an overall-SBS-HDC, defined as the total SB-CHINAE of HDC. To determine SBS-AE's criterion and construct validity, three self-rating scales and one clinician rating scale were used (German Clinical Trials Register, Main ID: DRKS00003453).
  
  
  RESULTS
  The SBS-AE's criterion validity could be verified both with statistical significance and at least medium-to-large effects (p < 0.05, Cohen's d > 0.79, f (2) > 0.18). The quantitative measured SB-CHINAE was equally associated with subjectively assessed physical health-related quality of life (0.15 ≤ R (2) ≤ 0.49), objectively evaluated toxicities (0.48 ≤ R (2) ≤ 0.67), transfusion-dependent thrombocytopenia, and anemia (Cohen's d > 0.89). Patients' somatic burden of HDC was 5.8-fold greater compared with standard chemotherapy regimens.
  
  
  CONCLUSIONS
  The SBS-AE indicates psychometric and clinical properties and may prove useful in the future design of cancer clinical trials and supportive care interventions inside of the inpatient setting.
authors.affiliation: Department of Hematology and Oncology, Otto-von-Guericke-University Magdeburg, Leipziger Straße 44, 39120, Magdeburg, Germany, michael.koehler@med.ovgu.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Koehler
authors.forename: Thomas
authors.initials: T
authors.lastname: Fischer
authors.forename: Siegfried
authors.initials: S
authors.lastname: Kropf
authors.forename: Joerg
authors.initials: J
authors.lastname: Frommer
mesh_terms: D000970:Antineoplastic Agents / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy*; D011446:Prospective Studies; D011788:Quality of Life; D011795:Surveys and Questionnaires
chemical_list: D000970:Antineoplastic Agents