title: Testing a theoretical model of perceived self-efficacy for cancer-related fatigue self-management and optimal physical functional status.
abstract: BACKGROUND
  Critical gaps exist in the understanding of cancer symptoms, particularly for cancer-related fatigue (CRF). Existing theories and models do not examine the key role perceived self-efficacy (PSE) plays in a person's ability to manage symptoms.
  
  
  OBJECTIVE
  The objective of this study was to test the hypothesis that physical functional status (PFS) is predicted through patient characteristics, CRF, other symptoms, and PSE for fatigue self-management in persons with cancer.
  
  
  METHODS
  This study is a secondary data analysis from the baseline observation of two randomized control trials. The combined data set includes 298 participants who were undergoing a course of chemotherapy. Key variables included physiological and contextual patient characteristics, the severity from CRF and other symptoms, PSE, and PFS. Path analysis examined the relationships among the variables in the proposed theoretical model.
  
  
  RESULTS
  Persons with cancer reported CRF as the most prevalent symptom among a mean of 7.4 other concurrent symptoms. The severity from CRF had a direct and indirect effect on PFS, with CRF having a direct adverse impact on PFS (t = -7.02) and an indirect adverse effect as part of the severity from the other symptoms (t = 9.69), which also adversely impacted PFS (t = -2.71). Consistent with the proposed theoretical model, PSE had a positive effect on the PFS (t = 2.87) of persons with cancer while serving as a mediator between CRF severity and PFS.
  
  
  CONCLUSIONS
  Cancer-related fatigue is prevalent and related to the presence of other symptoms, and PSE for fatigue self-management is an important factor influencing CRF and PFS. A foundation is provided for future intervention studies to increase PSE to achieve optimal PFS in persons with cancer.
authors.affiliation: Kirkhof College of Nursing, Cook DeVos Center for Health Sciences, Grand Valley State University, Grand Rapids, Michigan 49503-3314, USA. hoffmana@gvsu.edu
authors.forename: Amy J
authors.initials: AJ
authors.lastname: Hoffman
authors.forename: Alexander
authors.initials: A
authors.lastname: von Eye
authors.forename: Audrey G
authors.initials: AG
authors.lastname: Gift
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Given
authors.forename: Charles W
authors.initials: CW
authors.lastname: Given
authors.forename: Marilyn
authors.initials: M
authors.lastname: Rothert
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology*; D000223:Adaptation, Psychological; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001294:Attitude to Health; D016009:Chi-Square Distribution; D005221:Fatigue / Q000209:etiology / Q000517:prevention & control / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016294:Models, Nursing; D008960:Models, Psychological; D009369:Neoplasms / Q000150:complications*; D015403:Nursing Evaluation Research; D015404:Nursing Methodology Research; D011237:Predictive Value of Tests; D011594:Psychometrics; D012648:Self Care / Q000523:psychology*; D020377:Self Efficacy; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires