Document Detail


Estimates, power and sample size calculations for two-sample ordinal outcomes under before-after study designs.
MedLine Citation:
PMID:  12754716     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Sample size calculations are given for comparing two groups of subjects, typically referring to active and non-active intervention groups, on an ordinal outcome in experiments where the subjects are measured before and after intervention. These calculations apply to log-odds models with random intercepts, treatment, time and treatment-by-time interaction terms, the latter being the term of interest. The assumed forms of the odds ratios are flexible, allowing for proportional odds, adjacent categories, or other conditional models for ordinal responses. Simulations studies show that, for given sample sizes, the nominal and actual powers of the proposed test are similar.
Authors:
Pamela A Ohman Strickland; Shou-En Lu
Related Documents :
1765336 - Preliminary report on a new method of human age estimation from single adult teeth.
18978876 - Properties of high-numerical-aperture mueller-matrix polarimeters.
12964986 - Evolution of complex flowering strategies: an age- and size-structured integral project...
15514286 - Combined measurement of ferritin, soluble transferrin receptor, retinol binding protein...
23615956 - Toward the improvement of trail classification in national parks using the recreation o...
1608726 - Reliabilities, norms and factor structure of the behavioral dyscontrol scale.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Statistics in medicine     Volume:  22     ISSN:  0277-6715     ISO Abbreviation:  Stat Med     Publication Date:  2003 Jun 
Date Detail:
Created Date:  2003-05-19     Completed Date:  2003-09-17     Revised Date:  2007-11-15    
Medline Journal Info:
Nlm Unique ID:  8215016     Medline TA:  Stat Med     Country:  England    
Other Details:
Languages:  eng     Pagination:  1807-18     Citation Subset:  IM    
Copyright Information:
Copyright 2003 John Wiley & Sons, Ltd.
Affiliation:
Division of Biometrics, School of Public Health and Cancer Institute of New Jersey, University of Medicine of Dentistry of New Jersey, Suite 2200, Liberty Plaza, 335 George Street, New Brunswick, NJ 08903, USA. ohmanpa@umdnj.edu
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Clinical Trials as Topic / methods,  statistics & numerical data*
Data Interpretation, Statistical*
Humans
Odds Ratio
Sample Size*
United States

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Interim analysis of continuous long-term endpoints in clinical trials with longitudinal outcomes.
Next Document:  Robustness of sample size re-estimation procedure in clinical trials (arbitrary populations).