The scope of CDex is data sharing from providers to payers or providers to other providers.  If a provider exposes a CDex-compliant interface, they could certainly allow patients to access the data, though the filters in place may not necessarily be appropriate for patient consumption.  (The patients might have a right to access more data than a provider might typically disclose to a payer.)  CDex will not set any conformance expectations requiring that provider systems that declare CDex conformance to disclose to patients. In general, disclosure of data from provider to patient is covered by US Core, which will also have different work flows given the different business relationships.