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.

111 Reads
  • [Show abstract] [Hide abstract]
    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.
    Quality of Life Research 02/2013; 22(9). DOI:10.1007/s11136-013-0360-6 · 2.49 Impact Factor
  • [Show abstract] [Hide abstract]
    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.
    European journal of oncology nursing: the official journal of European Oncology Nursing Society 09/2013; 17(6). DOI:10.1016/j.ejon.2013.07.004 · 1.43 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives: This study examined the psychometric properties of the Multidimensional Fatigue Symptom Inventory-Short Form (MFSI-SF) in a community-based sample of African-Americans. Design: A sample of 340 African-Americans (116 men, 224 women) ranging in age from 18-81 years were recruited from the community (e.g., churches, health fairs, and beauty salons). Participants completed a brief demographic survey, the MFSI-SF and the Positive and Negative Affect Schedule. Results: The structural validity of the MFSI-SF for a community-based sample of African-Americans was not supported. The five dimensions of fatigue (General, Emotional, Physical, Mental, Vigor) found for Whites in prior research were not found for African-Americans in this study. Instead, fatigue, while multidimensional for African-Americans, was best represented by a unique four-four profile in which general and emotional fatigue are collapsed into a single dimension and physical fatigue, mental fatigue, and vigor are relatively distinct. Hence, in the absence of modifications, the MFSI-SF cannot be considered to be structurally invariant across ethnic groups. A modified four-factor version of the MFSI-SF exhibited excellent internal consistency reliability and evidence supports its convergent validity. Using the modified four-factor version, gender, and age were not meaningfully associated with MFSI-SF scores. Conclusion: Future research should further examine whether modifications to the MFSI-SF would, as the findings suggest, improve its validity as a measure of multidimensional fatigue in African-Americans.
    Ethnicity and Health 02/2014; 19(6). DOI:10.1080/13557858.2014.885933 · 1.67 Impact Factor
Show more