Purpose/objectives: To develop a clinically useful and psychometrically sound tool for the measurement of the distress from fatigue in patients with cancer.
Design: Instrument development of a numeric rating scale to assess cancer-related fatigue (CRF) distress.
Setting: A comprehensive cancer center and a Veterans Administration hospital.
Sample: The interview sample consisted of 17 adults with cancer experiencing CRF. The sample for instrument testing consisted of 221 adults with cancer. Twenty-nine different types of cancers were among the diagnoses. Seventy-eight percent of the participants were receiving some form of cancer treatment. The mean age was 60.
Methods: The Cancer-Related Fatigue Distress Scale (CRFDS) was developed from 23 in-depth audiotaped interviews with patients experiencing CRF. Krippendorff's content analysis procedures were used for interview analysis. Twenty-three items were generated. Five cancer survivors assessed content validity. Factor analysis was used to assess construct validity, and coefficient alpha was used to estimate the reliability of the CRFDS.
Findings: Factor analysis resulted in all items loading on one factor, indicating a single scale. The coefficient alpha was 0.98 after the elimination of three items.
Conclusions: The CRFDS has strong content validity, high reliability, and very good construct validity.
Implications for nursing practice: The CRFDS is a clinically useful and psychometrically sound tool for the measurement of CRF distress. This tool is clinically useful because of its brevity (20 items), clear instructions that required no training to use, and a readability score at the third-grade level.