Dignity Health, which operates dozens of hospitals in Arizona, California and Nevada, and giant tech vendor Optum have formed a joint venture to simplify vexing complexities in the realm of hospital billing and cost transparency. Dignity, based in San Francisco, will be the new venture's first client, reports sister paper, the San Francisco Business Times. Optum is a health care IT and technology unit of giant UnitedHealthcare. Both are divisions of Minneapolis-based UnitedHealth Group.