Final answer:
For post-operative care billing to CMS after a cataract surgery, the 90-day global period should be indicated starting from the surgery date, which is 1/1, to the end of the global period, which is 4/1.
Step-by-step explanation:
When billing CMS for post-operative care after cataract surgery with a 90-day global period, the date range for care provided should be indicated. The patient's surgery date is the start of the global period. In this case, the global period commences on 1/1, the day of surgery, and any post-operative care provided from that day until the end of the global period should be included. The date of transfer (1/2) does not affect the global period for the surgical procedure itself. Therefore, you should enter the date range for the post-operative care as 1/1–4/1 in the appropriate box on the CMS billing form.