title: A small sample randomized clinical trial methodology using N-of-1 designs and mixed model analysis.
abstract: OBJECTIVE
  To date, research on substance abuse prevention relied extensively on large sample randomized clinical trials to evaluate intervention programs. These designs are appropriate for certain types of randomized prevention trials (e.g., efficacy or effectiveness for broad populations) but are unfeasible for other prevention science scenarios (e.g., rare pathologies, pilot studies, or replication tests at specific locales).
  
  
  METHODS
  An alternative randomized clinical trial is described that relies on much smaller samples, less resources than the large sample designs, randomization, N-of-1 designs for the intervention group, and mixed model analysis.
  
  
  RESULTS
  This methodology is illustrated using a small sample prevention study, which demonstrates its statistical power, flexibility, and sophistication for experimental testing of prevention-oriented research questions.
  
  
  CONCLUSIONS
  This methodology can be applied to many existing prevention datasets to facilitate secondary analyses of existing datasets as well as novel studies. It is hoped that such efforts will include further development of the small sample design in substance abuse prevention contexts.
authors.affiliation: Center for Education and Drug Abuse Research, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.
authors.forename: Ty A
authors.initials: TA
authors.lastname: Ridenour
authors.forename: Deanne L
authors.initials: DL
authors.lastname: Hall
authors.forename: James E
authors.initials: JE
authors.lastname: Bost
mesh_terms: D000437:Alcoholism / Q000517:prevention & control; D000704:Analysis of Variance; D001786:Blood Glucose; D048909:Diabetes Complications / Q000517:prevention & control; D003920:Diabetes Mellitus / Q000097:blood; D006801:Humans; D015233:Models, Statistical; D016032:Randomized Controlled Trials as Topic / Q000379:methods*; D018401:Sample Size; D000074606:Smoking Prevention; D019966:Substance-Related Disorders / Q000517:prevention & control*; D016896:Treatment Outcome
chemical_list: D001786:Blood Glucose