Distinct qualities of N-of-1 trials

Although N-of-1 trials follow the basic structure of Randomized Control Trials (RCTs), they do have special features that distinguish them.

Blinding is difficult if not impossible

In an N-of-1 trial, it is often difficult to “blind” the participants to which type of treatment they’re receiving. That’s because the participants often give the treatments to themselves, and these interventions are often behavioral (such as trying yoga, sleeping at a different hour of the day, or getting more exercise). However, sometimes a trial can still be blinded, such as when a participant might test two types of medication and have someone else hide the labeling until the study is over.

Participants control how they want to carry out their study

In most research trials, participants have little control over the design of the protocol. If something about the approach isn’t working for them, there’s not much room to try  a new tactic such as taking a different dose or taking the treatment differently, so many may just drop out. 

In N-of-1 trials, because participants design or help design their own study, they can decide to stop if one intervention seems better than the others or they have all the information they need to make a decision. In this way,  the participant, not the researcher, is in control of the process.

Use of mobile information technology

Although not all N-of-1 trials use mobile phones, many do. This makes it possible to run a trial outside of a controlled research environment, using technology to send participants reminders about when to switch treatments and when to enter data about their experiences. Technology also makes it easier to give participants personalized analysis and feedback.