What explains a free testosterone that seems disproportionately elevated relative to total testosterone, particularly when SHBG isn't available to interpret the ratio in a male not taking supplemental T?

It’s a tricky question as we don’t know how free or total T was measured. If the total T was a biotinized assay, which most are, the total T could actually be spuriously high, so inquiring about biotin supplements and stopping them for 3 or more days before repeating the test is a good idea. If the ...

I would expect this finding if SHBG is low. Most of the circulating T is bound, so total T can be in the normal range with free T being high. Common causes of low SHBG: obesity, DM2, metabolic syndrome. Also, beware that direct assays of free T are often inaccurate.