The Healthcare Cost and Utilization Project (HCUP) is a family of healthcare databases and related software tools and products developed through a Federal-State-Industry partnership and sponsored by the Agency for Healthcare Research and Quality (AHRQ). Among the open software they make available, we can highlight:

- Clinical Classification System (CCS) for ICD-9-CM and ICD-10-CM.

- Chronic Condition Indicator (CCI).

- Elixhauser Comorbidity Software.

This open software tools can be used for the management of clinical-administrative databases with research purposes.

This is a RoMEO green journal. A paid open access option is available for this journal.

- Author can archive pre-print (ie pre-refereeing)

- Author can archive post-print (ie final draft post-refereeing)

- Author cannot archive publisher's version/PDF

That's a journal I'm interested in and it's listed as a ROMEO Green Journal.