Enhancing Transaction Security for Handling Accountability in Electronic Health Records

Table 1

Notations used in the proposed protocol.

Symbol	Definition
P	The subject and owner of the health records. A patient may have more than one PHR and EHR
C	Information consumer: an external entity that accesses PHRs, for example, a hospital, a lab, an emergency medical technician (EMT), or an insurance company
HCP	Healthcare professional: a hospital-based or clinical issuer of patient EHRs
Q	Any party that is involved in the transaction
V	Verifier, external third party
PID	Identity of the patient
CID	Identity of the information consumer
HCPID	Identity of healthcare professionals
Pri-Q	A private key of party Q, issued by a certificate authority
Pub-Q	A public key of party Q, issued by a certificate authority
T1, T2	Timestamps
h(M)	One-way hash function of message M
{M}Pub-Q	Message M encrypted with the public key of Q
{M}Pri-Q	Message M signed with the private key of Q
SK(A-B)	The session keys shared between party A and party B
ReqPHR	The request to use patient health records sent from the information consumer
PHR	Patients’ health information required by an involved party
Allow/NotAllow	The message status is sent from the patient to the healthcare professional to notify that the patient is allowed or not allowed to use the patient health records