What is the standard form used to bill outpatient claims?

"Although these forms look similar, they can't be used interchangeably. I understand the CMS-1450 is based on the CMS-1500. The UB-04 replaced the UB-92 back in 2007. Because of the complexities of hospital billing, the UB-04 has over twice as many field or blocks for all the different codes and services."

https://www.all-things-medical-billing.com/whats-the-difference-between-cms1500-and-ub04-or-cms1450