The development of instruments to measure self-management in youth with type 1 diabetes has not kept up with current understanding of the concept.
This study aimed to report the development and the testing of a new self-report measure to assess the Self-Management of Type 1 Diabetes in Adolescents (SMOD-A).
Following a qualitative study, items were identified and reviewed by experts for content validity. A total of 515 adolescents, 13 to 21 years old, participated in a field study by completing the SMOD-A (either once or twice) and additional measures of diabetes-related self-efficacy (Self-Efficacy for Diabetes Scale), quality of life (Diabetes Quality of Life for Youth Questionnaire), self-management (Diabetes Self-Management Profile), and adherence (Self-Care Inventory). Data were collected also on metabolic control (glycosylated hemoglobin [HbA1c]).
The content validity index was .93. Exploratory alpha factor analyses revealed five subscales: Collaboration With Parents, Diabetes Care Activities, Diabetes Problem Solving, Diabetes Communication, and Goals (α = .71 to .85). The stability of the SMOD-A ranged from .60 to .88 at 2 weeks (test-retest) to .59 to .85 at 3 months. Correlations of SMOD-A subscales with Self-Efficacy for Diabetes Scale-Diabetes; Diabetes Quality of Life for Youth Questionnaire satisfaction, impact, and worry; Diabetes Self-Management Profile; and Self-Care Inventory were generally significant and in the expected direction. Collaboration with parents and HbA1c values were related significantly and positively (r = .11); all other SMOD-A subscales were related significantly and negatively to HbA1c (r = −.10 to −.26), demonstrating that better self-management is associated somewhat with better metabolic control and supporting construct validity of the new measure.
The SMOD-A has been found to be a reliable, stable, and valid measure of SMOD-A.
Lynne S. Schilling, PhD, RN, is Professor and Associate Dean for Research and Director of the PhD Program, Graduate School of Nursing, University of Massachusetts Medical School, Worcester.
Jane K. Dixon, PhD, is Professor, School of Nursing, Yale University, New Haven, Connecticut.
Kathleen A. Knafl, PhD, is Associate Dean for Research and Frances Hill Fox Distinguished Professor; and Mary R. Lynn, PhD, is Professor, Assistant Director for Operations, Office of Human Research Ethics, School of Nursing, University of North Carolina at Chapel Hill.
Kathryn Murphy, PhD, is Associate Director; and Susan Dumser, MSN, is Clinical Nurse Specialist, Diabetes Center for Children, Children's Hospital of Philadelphia, Pennsylvania.
Margaret Grey, DrPH, is Dean and Annie Goodrich Professor, School of Nursing, Yale University, New Haven, Connecticut.
Editor's Note: Materials documenting the review process for this article are posted at http://www.nursing-research-editor.com.
Accepted for publication February 26, 2009.
This project was supported by a grant from the National Institutes of Health, National Institute of Nursing Research, R01NR08579. The authors thank Niki Federman for her project management and data collection at one of the study sites and Carol Bova, PhD, Associate Professor in the Graduate School of Nursing at the University of Massachusetts, Worcester, for her review and helpful suggestions regarding this manuscript.
Dr. Schilling began this work at Yale University, continued it at University of Massachusetts, Worcester, and, since submission of the manuscript, has retired.
The instrument described in this manuscript, Self-Management of Type 1 Diabetes in Adolescents (SMOD-A), is available from Lynne S. Schilling.
Corresponding author: Lynne S. Schilling, PhD, RN, Graduate School of Nursing, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA 01655 (e-mail: Lynne.Schilling@umassmed.edu).