Abstract
Objectives
To summarize the methods of design, analysis, and meta-analysis used in N-of-1 trials.
Study Design and Setting
Electronic search for English language articles published from 1950 to 2013. N-of-1
trials were selected if they followed an ABAB design and if they assessed a health
intervention for a medical condition. Elements of design, analysis, and meta-analysis
were extracted.
Results
We included 100 reports representing 1,995 participants. N-of-1 trials have been conducted
in over 50 health conditions. Most reports incorporated the use of elements that maintain
methodological rigor, including randomization, blinding, and formal outcome assessment;
however, many failed to address trial registration, funding source, and adverse events.
Most reports statistically analyzed individual N-of-1 trials; however, only a small
proportion of included series meta-analyzed their results.
Conclusions
N-of-1 trials have the ability to assess treatment response in individual participants
and can be used for a variety of health interventions for a wide range of medical
conditions in both clinical and research settings. Considerable heterogeneity exists
in the methods used in N-of-1 trials.
Keywords
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Article info
Publication history
Published online: April 11, 2016
Accepted:
March 22,
2016
Footnotes
Conflict of interest: L.H. is supported by a CIHR New Investigator Salary Award.
Funding: Funding support was provided in part by the Lotte and John Hecht Memorial Foundation.
Identification
Copyright
© 2016 Elsevier Inc. All rights reserved.
