What are some of the best N=1 study examples?

N=1 studies are at the heart of determining whether an outcome is actually caused by an intervention. (For example, does your 1 minute of high intensity training three times a week actually decrease your resting heart rate which is correlated with longevity.)

We heard that an N=1 focused magazine volume was being compiled at one time - but aren’t sure where that was.

Does anyone know of a great compilation of N=1 study examples, clinical or non-clinical, but particularly those focused on direct-to-consumer type interventions?

1 Like

Paper #1

A professor of mine just forwarded me this paper which was the best review I’ve seen on N=1 experimentation (Mirza et al. 2017): http://jameslindlibrary.org/wp-data/uploads/2017/02/J-R-Soc-Med-2017-08-Mirza-330-340.pdf

In particular, I noted these resources mentioned in the text: The N=1 “user’s guide” put out by Agency for Healthcare Research and Quality and the SPIRIT guidelines published by the Alberta Group. That practical advice could be helpful.

Additionally, it’s also helpful that they enumerated the major failings of the majority of current N=1 trials, as well as the areas (of mostly medicine) where N=1 trials have had the most success, like with ADHD.

Paper #2

Another fantastic paper (a little stats heavy) that’s hot off the press is this: https://arxiv.org/abs/1901.03423.

The author Eric J. Daza is worth a follow on twitter too, nice guy @ericjdaza


Somewhat off topic, but this is a interesting N=1 experiment that one could be quite confident in.

It goes like this:

  1. (Optional) Get your gut microbiome analyzed (services like uBiome do this for ~$90). They do 16S microbe RNA sequencing (not the more expensive ~$300 “shotgun” approach). Great info here if you’re interested.
    I believe uBiome’s report indicates potential food sensitivities (but I haven’t recieved mine yet, this might be true only for more expensive services like Viome). For example, they could say Bananas might spike your blood glucose, and you should consider avoiding them, or ideally, investigate further which leads us to…

  2. Conduct N=1 blood glucose trials with that food. On an empty stomach, measure your blood glucose (with finger-prick devices meant for diabetics but very useful to biohackers). Then eat the banana and see if you have an unacceptably large glucose spike (bad). You might want to repeat this a few times to be sure.

In the above example, the gut microbiome sequencing streamlines the process by providing a shortcut into which foods one should examine first, but isn’t strictly necessary. Also, I’m interested by the recent emergence of continuous glucose monitors (CGMs) in the form of a needle-less patch you apply to your arm that lasts for 2 weeks and measure glucose every 5 minutes. That new (painless) data vastly expands the possibilities data analysis and N=1 trials. Similar story for the falling cost of gut microbiome sequencing.

I’d love to hear anyone else’s research or ideas on N=1 experimentation!

1 Like

I realize this is more than what you asked for, but here’s a somewhat disorganized collection of papers related to N-of-1 studies:

N-of-1 Bibliography.bib (384.8 KB)

1 Like