We are all aware that the IRS uses ratio analysis to determine further scrutiny for their investigations.
So taking higher-than-average deductions on Schedule A is an audit red flag if your write-offs are disproportionately large when compared with income reported on your return.
In this case, a couple reported $38,000 of medical expenses. On audit, the couple could substantiate only about one-fifth of the total expenses.
Their deduction for the remaining $31,000 is toast
Detwiler, TC Summ. Op. 2021-28