Definition of Study, longitudinal
Study, longitudinal: A study done over the passage of time. For example, a longitudinal study of children with Down syndrome (trisomy 21) might involve the study of 100 children with this condition from birth to 10 years of age. Also called a diachronic study. The opposite of a cross-sectional (synchronic) study.
Last Editorial Review: 7/1/2016
Back to MedTerms online medical dictionary A-Z List
Need help identifying pills and medications?