Power and sample size determination for group comparison of patient-reported outcomes using polytomous Rasch models

Statistics in Medicine
J B HardouinV Sebille

Abstract

The analysis of patient-reported outcomes or other psychological traits can be realized using the Rasch measurement model. When the objective of a study is to compare groups of individuals, it is important, before the study, to define a sample size such that the group comparison test will attain a given power. The Raschpower procedure (RP) allows doing so with dichotomous items. The RP is extended to polytomous items. Several computational issues were identified, and adaptations have been proposed. The performance of this new version of RP is assessed using simulations. This adaptation of RP allows obtaining a good estimate of the expected power of a test to compare groups of patients in a large number of practical situations. A Stata module, as well as its implementation online, is proposed to perform the RP. Two versions of the RP for polytomous items are proposed (deterministic and stochastic versions). These two versions produce similar results in all of the tested cases. We recommend the use of the deterministic version, when the measure is obtained using small questionnaires or items with a few number of response categories, and the stochastic version elsewhere, so as to optimize computing time.

References

Jan 1, 1991·Journal of Clinical Epidemiology·D L SimelD B Matchar
Jan 18, 2005·Quality of Life Research : an International Journal of Quality of Life Aspects of Treatment, Care and Rehabilitation·J B BjornerUNKNOWN European Organisation for Research and Treatment of Cancer Quality of Life Group
Sep 1, 2006·Supportive Care in Cancer : Official Journal of the Multinational Association of Supportive Care in Cancer·David CellaLinda Elting
Nov 4, 2006·Pharmaceutical Statistics·Steven A Julious, Roger J Owen
Jan 30, 2008·Journal of Clinical Oncology : Official Journal of the American Society of Clinical Oncology·Carolyn C GotayFabio Efficace
May 21, 2009·Statistics in Medicine·Stephen Senn, Steven Julious
Feb 1, 2012·International Journal of Methods in Psychiatric Research·Thomas M OlinoPeter M Lewinsohn
Feb 9, 2012·Journal of Family Psychology : JFP : Journal of the Division of Family Psychology of the American Psychological Association (Division 43)·Anita JoseK Daniel O'Leary
Nov 2, 2012·PloS One·Jean-François HamelVéronique Sébille
Mar 13, 2013·The New England Journal of Medicine·André LamyUNKNOWN CORONARY Investigators
Apr 4, 2013·JAMA : the Journal of the American Medical Association·Ellen M Lavoie SmithUNKNOWN Alliance for Clinical Trials in Oncology
May 20, 2015·Journal of Nursing Measurement·Ulla Fredriksson-LarssonÅsa Lundgren-Nilsson

❮ Previous
Next ❯

Citations

Nov 9, 2016·BMC Medical Research Methodology·Lorenzo G TanadiniTorsten Hothorn
Dec 20, 2015·Medical Decision Making : an International Journal of the Society for Medical Decision Making·Antoine BarbieriCaroline Bascoul-Mollevi
Sep 28, 2017·BMC Medical Research Methodology·Antoine BarbieriCaroline Mollevi

❮ Previous
Next ❯

Related Concepts

Related Feeds

Addiction

This feed focuses mechanisms underlying addiction and addictive behaviour including heroin and opium dependence, alcohol intoxication, gambling, and tobacco addiction.