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May
2011

In longitudinal studies of developmental and disease processes, participants are followed prospectively with intermediate milestones identified as they occur. Frequently, studies enroll participants over a range of ages including ages at which some participants' milestones have already passed. Ages at milestones that occur prior to study entry are left censored if individuals are enrolled in the study or left truncated if they are not.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3121224PMCFound
http://dx.doi.org/10.1093/aje/kwq481DOI ListingPossible


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Sep
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Aug
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Sep
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Dec
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