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Article: How attrition impacts the internal and external validity of longitudinal research.(Commentaries)
- Article from:
- Journal of School Health
- Article date:
- September 1, 2005
- Author:
CopyrightCOPYRIGHT 2005 American School Health Association. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Longitudinal research produces more reliable evidence concerning causality by gathering data directly from participants, preintervention and postintervention, utilizing 1 or more follow-up studies at the conclusion. The process of surveying at different points in time ameliorates direction-of-effect problems. (1) While there are considerable benefits when conducting longitudinal research, potential problems associated with subject attrition, also known as mortality, tend to reduce or overwhelm the benefits. (2) Plewis contends, "Perhaps the criticism voiced most often about longitudinal studies is that they suffer from such serious problems of sample loss over time as to ...