Research fundamentals: follow-up of subjects in clinical trials: addressing subject attrition.
Many published clinical trials have less than adequate follow-up. When conducting a clinical trial, researchers attempt to minimize data loss; however, some data may not be collected, particularly when subjects are lost to follow-up. Careful planning of research protocols, including comprehensive initial data collection, identification of locators, flexible scheduling, systematic subject tracking, monitoring subject loss, and systematically approaching problem cases can ensure high follow-up rates. This article presents a compendium of techniques and procedures that researchers can use to enhance follow-up and address attrition in their studies. Finally, this article outlines statistical techniques that can be used to address the effects of missing data, particularly when patients are lost to follow-up.
Woolard
Robert H
RH
Department of Emergency Medicine, Rhode Island Hospital, Brown University School of Medicine, Providence, RI 02903, USA. rwoolard@lifespan.org
Carty
Kathleen
K
Wirtz
Philip
P
Longabaugh
Richard
R
Nirenberg
Ted D
TD
Minugh
P Allison
PA
Becker
Bruce
B
Clifford
Patrick R
PR
D001071:Appointments and Schedules; D002986:Clinical Trials as Topic / Q000379:methods* / Q000592:standards; D003627:Data Interpretation, Statistical; D004635:Emergency Medicine / Q000379:methods*; D005500:Follow-Up Studies; D006801:Humans; D007407:Interviews as Topic / Q000379:methods; D011369:Professional-Patient Relations; D045808:Refusal to Participate; D015203:Reproducibility of Results; D035842:Research Subjects