From the email USUHS sent before my interview:
"Dressing for the Occasion
Remember that less is more! Professional business attire is most appropriate. A suit or skirt/pants with jacket, and simple shoes would be sufficient. Avoid loud or multiple colors. Keep accessories to a minimum; makeup and fragrances should be moderate. Military persons (i.e. ROTC, Academy, active duty and reservists) are strongly encouraged to wear their dress uniforms, (AF-Service Dress, A-Class A, and N-Service Dress Blues). If guests will accompany you, it is advisable that they dress in business casual attire."
Hope that helps.