5 posts
The Yale calculator is Levine's PhenoAge: a nine-biomarker mortality model fit in NHANES III and rescaled into years. Here are the coefficients, the unit traps, the noise floor, and how we would track it over time.
There are two products sold as a 'methylation report': an MTHFR-style SNP panel from genotyping data, and a genome-wide DNA methylation array read out as epigenetic clocks. They measure different things, and only one of them is a measurement of your current biology.
Most online biological age calculators are quizzes. Here is what the published estimators take as input, how to compute them from your own blood panel or methylation array, and how much weight the output deserves.
Levine's PhenoAge is a nine-marker blood algorithm you can compute yourself in about twenty lines of Python. Here is the formula, the unit conversions that break it, and how it compares to the methylation clocks from the same lab.
No single lifespan blood test exists. A small set of analytes together predicts all-cause mortality. How to order, store and recompute them.