An n-of-1 trial is a experiment conducted for a single person in which treatment blocks are randomly rotated, symptoms are systematically logged, and results are statistically analyzed. Since many treatments work differently for individuals, n-of-1 trials help determine a treatment’s efficacy for a specific individual. N-of-1 trials are typically used for chronic conditions and are not considered appropriate for acute illnesses.
Though doctors and drug makers tout “average” effects, many treatments deliver a smorgasbord of results—substantial benefits for some people, little benefit for many, and harm for a few. Why don’t we hear more about this variability?
Most people’s tests of potential treatments for chronic conditions involve haphazard cycling through doses and brands, spotty symptom diaries and no statistical analysis of results. This lack of rigor introduces numerous cognitive biases.
The literature on treatment blocks says broadly that blocks may be shorter for faster acting treatments (a one day treatment might be appropriate for pain and aspirin) and longer for treatments that have a slow, cumulative effect. But digging into the literature for both RTCs and n-of-1 experiments, you find a wide variety of treatment […]