Development of a fatigue and functional impact scale in anemic cancer patients receiving chemotherapy.
BACKGROUND
This study was conducted to develop a brief measure of fatigue and functional impact in cancer patients with anemia.


METHODS
Data were obtained from a multisite, phase 2 study of darbepoetin-alpha (n = 1,558). Eligible patients were >or=18 years with nonmyeloid malignancies and anemia (hemoglobin <or=11 g/dL) who were receiving chemotherapy. Items from the Functional Assessment of Cancer Therapy-Fatigue (FACT-F), Brief Fatigue Inventory (BFI), Fatigue Symptom Inventory (FSI), and items adapted from the Medical Outcomes Study SF-36 physical functioning scale were evaluated for inclusion in the measure. Items were selected by identifying the best predictors of total FACT-F scores, hemoglobin, and adjusted maximum oxygen uptake (VO(2)Max) in regression models. Correlations were examined between scale scores and adjusted VO(2)Max, hemoglobin, performance status, self-reported energy, and productivity.


RESULTS
Data from 401 patients with complete data were used to identify 8 items for the Fatigue and Functional Impact Scale (FFIS), which was then evaluated using 1,355 of the 1,558 patients. The FFIS had an estimated internal consistency reliability of 0.90. The FFIS had significant correlations with the FACT-F (r = 0.94), FSI (r = 0.80), and BFI (r = 0.86), from which it was derived. The FFIS also correlated substantially with single-item measures of energy (r = 0.75) and productivity (r = 0.72).


CONCLUSIONS
The FFIS is a reliable, brief, and practical tool that is potentially suitable for identifying fatigue and functional impact in cancer patients.
Cella
David
D
Center on Outcomes Research and Education, Evanston Northwestern Healthcare and Northwestern University, Evanston, Illinois 60201, USA. d-cella@northwestern.edu
Viswanathan
Hema N
HN
Hays
Ron D
RD
Mendoza
Tito R
TR
Stein
Kevin D
KD
Pasta
David J
DJ
Foreman
Aimee J
AJ
Vadhan-Raj
Saroj
S
Kallich
Joel D
JD
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000150:complications / Q000188:drug therapy*; D017322:Clinical Trials, Phase II as Topic; D000068256:Darbepoetin alfa; D004921:Erythropoietin / Q000031:analogs & derivatives / Q000627:therapeutic use; D005221:Fatigue / Q000175:diagnosis / Q000209:etiology*; D005260:Female; D006397:Hematinics / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D009369:Neoplasms / Q000150:complications* / Q000188:drug therapy; D011237:Predictive Value of Tests; D011788:Quality of Life; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires
D006397:Hematinics; D004921:Erythropoietin; D000068256:Darbepoetin alfa