Please help me understand this tax question

A practitioner is figuring the maximum calculation to an SEP for a year. SEP contributions are limited to a percent of earned income. A practitioner asks if the 2% S-corporation shareholder health insurance paid by a corporation but required to be included in box 1 of a W-2 is included as compensation for the SEP contribution calculation, or should the Box 5 calculation excluding health insurance be used? (There are several IRC code sections which apply to this answer).