Abstract
Results obtained from self-reported health data may be biased if those being surveyed respond differently based on health status. This study was conducted to investigate if health, as measured by health care use preceding invitation, influenced response to invitation to a 21-year prospective study, the Millennium Cohort Study. Inpatient and outpatient diagnoses were identified among more than 68,000 people during a one-year period prior to invitation to enroll. Multivariable logistic regression defined how diagnoses were associated with response. Days spent hospitalized or in outpatient care were also compared between responders and nonresponders. Adjusted odds of response to the questionnaire were similar over a diverse range of inpatient and outpatient diagnostic categories during the year prior to enrollment. The number of days hospitalized or accessing outpatient care was very similar between responders and nonresponders. Study findings demonstrate that, although there are some small differences between responders and nonresponders, prior health care use did not affect response to the Millennium Cohort Study, and it is unlikely that future study findings will be biased by differential response due to health status prior to enrollment invitation.
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Abbreviations
- CI:
-
Confidence interval
- ICD-9-CM:
-
International Classification of Diseases, Ninth Revision, Clinical Modification
- OR:
-
Odds ratio
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Acknowledgments
We are indebted to the Millennium Cohort Study participants, without whom these analyses would not be possible. We thank Scott L. Seggerman from the Management Information Division, Defense Manpower Data Center, Seaside, California. Additionally, we thank Laura Chu, MPH; Lacy Farnell; Gia Gumbs, MPH; Cynthia LeardMann, MPH; Travis Leleu; Steven Spiegel; Damika Webb; Keri Welch, MA; and Jim Whitmer from the Department of Defense Center for Deployment Health Research, Naval Health Research Center, San Diego, California; and Michelle Stoia, also from the Naval Health Research Center. We appreciate the support of the Henry M. Jackson Foundation for the Advancement of Military Medicine, Rockville, Maryland.
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In addition to the authors, the Millennium Cohort Study Team includes Edward J. Boyko, MD, MPH (Seattle Epidemiologic Research and Information Center, Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA); Gary D. Gackstetter, PhD, DVM, MPH and Tomoko I Hooper, MD MPH (Department of Preventive Medicine and Biometrics, Uniformed Services University of the Health Sciences, Bethesda, MD); Gary D. Gackstetter, PhD, DVM, MPH (Analytic Services, Inc. (ANSER), Arlington, VA); Gregory C. Gray, MD, MPH (College of Public Health, University of Iowa, Iowa City, IA); and James R. Riddle, DVM, MPH (Air Force Research Laboratory, Wright-Patterson Air Force Base, OH).
This represents report 07-07, supported by the Department of Defense, under work unit no. 60002. The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of the Army, Department of the Air Force, Department of Defense, Department of Veterans Affairs, or the US Government. This research has been conducted in compliance with all applicable federal regulations governing the protection of human subjects in research (Protocol NHRC.2000.007).
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Wells, T.S., Jacobson, I.G., Smith, T.C. et al. Prior health care utilization as a potential determinant of enrollment in a 21-year prospective study, the Millennium Cohort Study. Eur J Epidemiol 23, 79–87 (2008). https://doi.org/10.1007/s10654-007-9216-0
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DOI: https://doi.org/10.1007/s10654-007-9216-0