Validating the 4Leaf Survey

It’s Time to Formally Validate the 4Leaf Survey

So that it can become the most important vital sign in medicine

But let’s start at how 4Leaf started. Everything started with Dr. T. Colin Campbell’s definition of an optimal diet for humans

“The closer we get to eating a diet of whole, plant-based foods, the better off we will be.”

Gorillas (whose DNA is closest to ours) gets over 99% of his calories from those healthiest of foods. The average American gets far less than 10%. Our survey currently does a very good job of identifying the people who need the most help. It’s all of the people whose first 4Leaf score is a negative number. And we have found that, among typical Americans, 90% of them will score in that group. And upon seeing their first 4Leaf score, most people are motivated to get a lot more serious about what they are eating.

We are currently gathering/analyzing data aimed at determining the correlation of the 4Leaf score to changes in blood pressure, A1C, total cholesterol and BMI. Please advise if you have data that you can share with us.

Ideally, we’d like to have something like this:

  • 100 new patients take the survey every three months for a year (a total of five iterations)
  • To the extent possible, their respective blood pressure, A1C, total cholesterol and/or BMI would be measured at the same time.
  • We are confident that a rising 4Leaf score will correlate strongly to improving bio-markers across the board.
  • We don’t need to validate the survey score’s accuracy in “estimating” percent of calories from whole plants. Rather, the survey provides us a simple and quick pattern of eating that the patient can easily understand and report from memory.

Maybe some of this kind of information is in your database now. If so, we would love to have the opportunity to analyze that data.

4Leaf Credibility

Here’s what we have so far. Four medical doctors (with combined survey use in the thousands) have told us that they already consider the 4Leaf score to be a vital sign (ranging from -44 to +44) and are actually entering it into their respective EMR systems. And they seem to  feel that it is the most important vital sign; in the sense that the patient can easily take steps to improve that vital sign from a very unhealthy diet (below -20) to very healthy diet (over +30) in just a few months.

In the process, many of the traditional vital signs are improved as the patient moves toward the vibrant health that a whole food, plant-based diet can deliver.

Our goal is to someday see the 4Leaf score on the “vital sign” list of  EMR systems everywhere. And the more validation we can produce, the greater the likelihood that will happen. As we gather more validation data for the 4Leaf Survey, we will update this list. Right now, here’s what we have in the way of credibility:

  • Since 2014, the 4Leaf Survey has been used at eCornell in the  T. Colin Campbell Certificate Course in Plant-Based Nutrition. See
  • British paper re “Diet vs. Breathing” relationship (January 2019) M. Lingard, Osteopath, who is one of our licensees. Check out how the 4Leaf score clearly correlates with improved health as measured by the Buteyko Method.
  • Michael Lingard, DO, mentions the 4Leaf Survey twice in an April 2018 article on the Center for Nutrition Studies website.
  • Finally, we have an enormous amount of anecdotal data from physicians who are using the 4Leaf Survey in their practice. At least four of those doctors have each purchased between 100 and 1,000 copies of our book.

Regarding formal validation, here’s where we are as of March 7, 2019

1. What are we trying to validate?

  • That the survey accurately estimates the percent of food calories from whole plants? OR..
  • That the survey score has a positive correlation with more than one bio marker: like BP, total cholesterol, A1C and/or BMI. As the score goes up, the biomarkers get better.
  • Or both?

2. Can we use existing data that has been gathered by a host of medical doctors  to prove the second premise above?

In answer to #1, our thinking is that the positive correlation would be easier to prove than the actual percent of calories from whole plants. For that, we’d need a lot more than twelve questions, it would be more complex, it would no doubt have many inaccuracies and it would no longer be a two-minute survey.

Many doctors have told us that the best thing about the survey is that it is easy, fast, and does a great job of helping the patient understand that they are eating nowhere near a health promoting diet. They also report that the realization of that fact can be very motivating for the patient.

That’s it for now, refer back to this page to check on our progress.

J. Morris (Jim) Hicks, Founder & CEO, 4Leaf Global, LLC.

PS: One fine day in September of 2015, I received this unsolicited endorsement via email from T. Colin Campbell, PhD, Nutritional Biochemistry, Cornell University. He sent it from an international cancer conference.

“Your 4Leaf model is one-hundredth the complexity but has real value that may exceed any of the very comprehensive survey models developed by some of the world’s top cancer specialists.”–T. Colin Campbell, PhD

Copyright © 2019, 4Leaf Global, LLC

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