The Piper Fatigue Scale-12 (PFS-12): Psychometric findings and item reduction in a cohort of breast cancer survivors

Department of Health Policy & Management, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 1101-D McGavran-Greenberg Hall, 135 Dauer Drive, CB 7411, Chapel Hill, NC, 27599-7411, USA, .
Breast Cancer Research and Treatment (Impact Factor: 3.94). 08/2012; 136(1):9-20. DOI: 10.1007/s10549-012-2212-4
Source: PubMed


Brief, valid measures of fatigue, a prevalent and distressing cancer symptom, are needed for use in research. This study's primary aim was to create a shortened version of the revised Piper Fatigue Scale (PFS-R) based on data from a diverse cohort of breast cancer survivors. A secondary aim was to determine whether the PFS captured multiple distinct aspects of fatigue (a multidimensional model) or a single overall fatigue factor (a unidimensional model). Breast cancer survivors (n = 799; stages in situ through IIIa; ages 29-86 years) were recruited through three SEER registries (New Mexico, Western Washington, and Los Angeles, CA) as part of the Health, Eating, Activity, and Lifestyle (HEAL) study. Fatigue was measured approximately 3 years post-diagnosis using the 22-item PFS-R that has four subscales (Behavior, Affect, Sensory, and Cognition). Confirmatory factor analysis was used to compare unidimensional and multidimensional models. Six criteria were used to make item selections to shorten the PFS-R: scale's content validity, items' relationship with fatigue, content redundancy, differential item functioning by race and/or education, scale reliability, and literacy demand. Factor analyses supported the original 4-factor structure. There was also evidence from the bi-factor model for a dominant underlying fatigue factor. Six items tested positive for differential item functioning between African-American and Caucasian survivors. Four additional items either showed poor association, local dependence, or content validity concerns. After removing these 10 items, the reliability of the PFS-12 subscales ranged from 0.87 to 0.89, compared to 0.90-0.94 prior to item removal. The newly developed PFS-12 can be used to assess fatigue in African-American and Caucasian breast cancer survivors and reduces response burden without compromising reliability or validity. This is the first study to determine PFS literacy demand and to compare PFS-R responses in African-Americans and Caucasian breast cancer survivors. Further testing in diverse populations is warranted.

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    ABSTRACT: Purpose: To empirically determine clinically meaningful cut-scores on the 0-10 response scale of the revised Piper Fatigue Scale (PFS-R) and its shorter version (PFS-12). Breast cancer survivors were classified (i.e., none, mild, moderate, or severe fatigue) based on the cut-scores, and relationships between these cut-scores and decrements in health-related quality of life (HRQOL) were examined. Methods: A total of 857 breast cancer survivors, stages in situ-IIIa, from the Health, Eating, Activity, and Lifestyle (HEAL) Study were eligible. Survivors completed the PFS-R, SF-36, and a sexual health scale approximately 3 years after diagnosis. Multivariate analysis of covariance was used to examine five fatigue severity cut-score models, controlling for demographics, clinical characteristics, comorbidity, and antidepressant use. Multivariate regression was used to examine HRQOL decrements by cut-score category. Results: Analyses supported two similar fatigue severity cut-score models for the PFS-R and PFS-12: Model A.) none (0), mild (1-3), moderate (4-6), and severe (7-10); and Model D.) none (0), mild (1-2), moderate (3-5), and severe (6-10). For every threshold increase in fatigue severity, clinically meaningful decrements in physical, mental, and sexual health scores were observed, supporting construct validity of the fatigue cut-scores. Conclusion: Standardized fatigue cut-scores may enhance interpretability and comparability across studies and populations and guide treating planning.
    No preview · Article · Feb 2013 · Quality of Life Research
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    ABSTRACT: The Revised Piper Fatigue scale is one of the most widely used instruments internationally to assess cancer-related fatigue. The aim of the present study was to evaluate selected psychometric properties of a Swedish version of the RPFS (SPFS). An earlier translation of the SPFS was further evaluated and developed. The new version was mailed to 300 patients undergoing curative radiotherapy. The internal validity was assessed using Principal Axis Factor Analysis with oblimin rotation and multitrait analysis. External validity was examined in relation to the Multidimensional Fatigue Inventory-20 (MFI-20) and in known-groups analyses. Totally 196 patients (response rate = 65%) returned evaluable questionnaires. Principal axis factoring analysis yielded three factors (74% of the variance) rather than four as in the original RPFS. Multitrait analyses confirmed the adequacy of scaling assumptions. Known-groups analyses failed to support the discriminative validity. Concurrent validity was satisfactory. The new Swedish version of the RPFS showed good acceptability, reliability and convergent and- discriminant item-scale validity. Our results converge with other international versions of the RPFS in failing to support the four-dimension conceptual model of the instrument. Hence, RPFS suitability for use in international comparisons may be limited which also may have implications for cross-cultural validity of the newly released 12-item version of the RPFS. Further research on the Swedish version should address reasons for high missing rates for certain items in the subscale of affective meaning, further evaluation of the discriminative validity and assessment of its sensitivity in detecting changes over time.
    No preview · Article · Sep 2013 · European journal of oncology nursing: the official journal of European Oncology Nursing Society
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    ABSTRACT: Background: Cancer-related fatigue (CRF) is the most common and distressing symptom reported by breast cancer survivors with evidence of significant negative impact on a patient's quality of life. There is no consensus for measurement of CRF in persons diagnosed with breast cancer. Purpose/Objective: The purpose of this study is to identify valid and reliable evidence-based tools to measure CRF in persons diagnosed with breast cancer as a screening and/or an evaluation tool utilizing the American Physical Therapy Association Oncology Section Cancer Evaluation Database to Guide Effectiveness (EDGE) Taskforce Outcome Measure Rating Form. Methods: A systematic literature review from 2002-2012 was completed to identify measurement tools for CRF utilized in persons diagnosed with breast cancer. The one-dimensional and multidimensional measurement tools identified were further evaluated for their psychometric properties using the modified EDGE criteria. Results: Out of 43 measurement tools only 3 met the criteria to be classified as highly recommended. They include one one-dimensional tool, the Brief Fatigue Inventory, and two multidimensional measurement tools, the Functional Assessment of Cancer Therapy-Breast cancer subscale, and the Multidimensional Fatigue Symptom Inventory-Short Form. Limitations: Some studies lacked psychometric data for measurement tool validation with persons diagnosed with breast cancer or the breast cancer specific data was unable to be separated from other participants in the study. Conclusions: Further studies are warranted to consider the applicability of one or multidimensional measurement tools for screening versus evaluation of CRF.
    No preview · Article · Jan 2014
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