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A model-based approach to sample size estimation in recent onset type 1 diabetes.

ABSTRACT: The area under the curve C-peptide following a 2-h mixed meal tolerance test from 498 individuals enrolled on five prior TrialNet studies of recent onset type 1 diabetes from baseline to 12 months after enrolment were modelled to produce estimates of its rate of loss and variance.Age at diagnosis and baseline C-peptide were found to be significant predictors, and adjusting for these in an ANCOVA resulted in estimates with lower variance.Using these results as planning parameters for new studies results in a nearly 50% reduction in the target sample size. The modelling also produces an expected C-peptide that can be used in observed versus expected calculations to estimate the presumption of benefit in ongoing trials. Copyright © 2016 John Wiley & Sons, Ltd.

SUBMITTER: Bundy BN

PROVIDER: S-EPMC5117187 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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A model-based approach to sample size estimation in recent onset type 1 diabetes.

Bundy Brian N BN Krischer Jeffrey P JP

Diabetes/metabolism research and reviews 20160421 8

<h4>Background</h4>The area under the curve C-peptide following a 2-h mixed meal tolerance test from 498 individuals enrolled on five prior TrialNet studies of recent onset type 1 diabetes from baseline to 12 months after enrolment were modelled to produce estimates of its rate of loss and variance.<h4>Results</h4>Age at diagnosis and baseline C-peptide were found to be significant predictors, and adjusting for these in an ANCOVA resulted in estimates with lower variance.<h4>Conclusions</h4>Usin ...[more]

PMID: 26991448

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