3 posts
A testosterone test is only interpretable if you control the timing, the assay, and the companion measurements. Here is the panel we would order, why free testosterone by calculation beats direct immunoassay, and how to read the numbers.
DNA age tests read cytosine methylation at a few hundred CpG sites and regress it onto chronological age. Here is how the assay works, which clocks are worth running, what the error bars really are, and how to process the raw data yourself.
A consumer epigenetics kit measures DNA methylation at CpG sites on an array, then feeds those values into a regression model that outputs an age-like number. Here is what the assay does, what the error bars are, and how to work with the raw IDAT files yourself.