The PedsQL™ Multidimensional Fatigue Scale in Pediatric Rheumatology: Reliability and Validity

JAMES W. VARNI, TASHA M. BURWINKLE, and ILONA S. SZER

ABSTRACT.

Objective. The PedsQL™ (Pediatric Quality of Life Inventory™) is a modular instrument designed to measure health related quality of life (HRQOL) in children and adolescents ages 2–18 years. The recently developed 18-item PedsQL Multidimensional Fatigue Scale was designed to measure fatigue in pediatric patients and comprises the General Fatigue Scale (6 items), Sleep/Rest Fatigue Scale (6 items), and Cognitive Fatigue Scale (6 items). The PedsQL 4.0 Generic Core Scales were developed as the generic core measure to be integrated with the PedsQL Disease-Specific Modules. The PedsQL 3.0 Rheumatology Module was designed to measure pediatric rheumatology-specific HRQOL.

Methods. The PedsQL Multidimensional Fatigue Scale, Generic Core Scales, and Rheumatology Module were administered to 163 children and 154 parents (183 families accrued overall) recruited from a pediatric rheumatology clinic.

Results. Internal consistency reliability for the PedsQL Multidimensional Fatigue Scale Total Score (a = 0.95 child, 0.95 parent report), General Fatigue Scale (a = 0.93 child, 0.92 parent), Sleep/Rest Fatigue Scale (a = 0.88 child, 0.90 parent), and Cognitive Fatigue Scale (a = 0.93 child, 0.96 parent) were excellent for group and individual comparisons. The validity of the PedsQL Multidimensional Fatigue Scale was confirmed through hypothesized intercorrelations with dimensions of generic and rheumatology-specific HRQOL. The PedsQL Multidimensional Fatigue Scale distinguished between healthy children and children with rheumatic diseases as a group, and was associated with greater disease severity. Children with fibromyalgia manifested greater fatigue than children with other rheumatic diseases.

Conclusion. The results confirm the initial reliability and validity of the PedsQL Multidimensional Fatigue Scale in pediatric rheumatology. (J Rheumatol 2004;31:2494-500)

Key Indexing Terms:

HEALTH RELATED QUALITY OF LIFE
FATIGUE
RHEUMATOLOGY
PEDIATRICS
CHILDREN

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From the Department of Landscape Architecture and Urban Planning, College of Architecture, Department of Pediatrics, College of Medicine, Texas A&M University, College Station, Texas; Department of Anesthesiology, University of Washington, Seattle, Washington; and Division of Pediatric Rheumatology, Children's Hospital and Health Center, Department of Pediatrics, University of California School of Medicine, San Diego, California, USA.

Supported by research grants from The Arthritis Foundation.

J.W. Varni, PhD, Department of Landscape Architecture and Urban Planning, College of Architecture, Department of Pediatrics, College of Medicine, Texas A&M University; T.M. Burwinkle, PhD, Department of Anesthesiology, University of Washington; I.S. Szer, MD, Division of Pediatric Rheumatology, Children's Hospital and Health Center, Department of Pediatrics, University of California School of Medicine.

Address reprint requests to Dr. J.W. Varni, Department of Landscape Architecture and Urban Planning, College of Architecture, Texas A&M University, 3137 TAMU, College Station, TX 77843-3137. E-mail: jvarni@archone.tamu.edu.

Submitted November 17, 2003; revision accepted July 12, 2004.

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