Abstract
N-of-1 trials are extremely useful in subject-focused investigations, for example, medical experiments. As far as we are aware, no guidelines are available in the literature on how to plan such a trial optimally. In this chapter, we discuss the considerations when choosing a particular N-of-1 trial design. We assume that the outcome of interest is measured on a continuous scale. Our discussion will be limited to comparisons of two treatments, without implying that the designs constructed can apply to non-continuous or binary outcomes. We construct optimal N-of-1 trials under various models depending upon how we accommodate the carryover effects and the error structures for the repeated measurements. Overall, we conclude that alternating between AB and BA pairs in subsequent cycles will result in practically optimal N-of-1 trials for a single patient, under all the models we considered without the need to guess at the correlation structure or conduct a pilot study. Alternating between AB and BA pairs in a single trial is nearly robust to misspecification of the error structure of the repeated measurements.
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This research was made possible due to the funding from the Natural Sciences and Engineering Research Council of Canada.
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Carriere, K.C., Li, Y., Mitchell, G., Senior, H. (2015). Methodological Considerations for N-of-1 Trials. In: Nikles, J., Mitchell, G. (eds) The Essential Guide to N-of-1 Trials in Health. Springer, Dordrecht. https://doi.org/10.1007/978-94-017-7200-6_6
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DOI: https://doi.org/10.1007/978-94-017-7200-6_6
Publisher Name: Springer, Dordrecht
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