title: Item-level factor analysis of the Self-Efficacy Scale.
abstract: This study explores the internal structure of the Self-Efficacy Scale (SES) using item response analysis. The SES was previously translated into Swedish and modified to encompass all types of pain, not exclusively back pain. Data on perceived self-efficacy in 47 patients with subacute whiplash-associated disorders were derived from a previously conducted randomized-controlled trial. The item-level factor analysis was carried out using a six-step procedure. To further study the item inter-relationships and to determine the underlying structure empirically, the 20 items of the SES were also subjected to principal component analysis with varimax rotation. The analyses showed two underlying factors, named 'social activities' and 'physical activities', with seven items loading on each factor. The remaining six items of the SES appeared to measure somewhat different constructs and need to be analysed further.
authors.affiliation: Department of Clinical Neuroscience and Rehabilitation, Center for Brain Repair and Rehabilitation, Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Lina
authors.initials: L
authors.lastname: Bunketorp Käll
mesh_terms: D000203:Activities of Daily Living / Q000145:classification / Q000523:psychology; D000293:Adolescent; D000328:Adult; D003299:Cooperative Behavior; D003431:Cross-Cultural Comparison; D005260:Female; D006801:Humans; D055809:Illness Behavior; D033183:Interdisciplinary Communication; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D011594:Psychometrics / Q000706:statistics & numerical data; D011788:Quality of Life / Q000523:psychology; D015203:Reproducibility of Results; D020377:Self Efficacy; D011795:Surveys and Questionnaires; D013548:Sweden; D014175:Translating; D014911:Whiplash Injuries / Q000523:psychology* / Q000534:rehabilitation*; D055815:Young Adult