An Application Programming Interface for the Electronic Transmission of Prescriptions

1. An Application Programming Interface for the Electronic Transmission of Prescriptions • Synopsis • Prescribing in the UK • The Pilots and Salford Models • Potential Benefits / Problems • Present Status Presented By: D. P. Mundy Other Authors: Prof. D. W. Chadwick, Dr E. Ball Thanks to: ISSRG Information Systems Security Research Group Contact: D.Mundy@salford.ac.uk http://sec.isi.salford.ac.uk

2. Synopsis • The United Kingdom (UK) National Health Service (NHS) • NHS Plan • Implement ETP by 2004 • 3 pilot systems • Transcript consortium (Large pharmacies and Pharmed) • Pharmacy2U consortium (An Internet pharmacy) • Flexiscript consortium (Microsoft, SchlumbergerSema)

3. Salford ETP Project • Funded by the UK’s Engineering and Physical Sciences Research Council (EPSRC) • 3 Year Project commenced September 2000 • Carried out in collaboration with Huddersfield University and Hope Hospital, Salford • £261k funding

4. Prescribing in the UK 3. Drugs Dispensed to Patient, money to dispenser if the patient is not exempt 5. Prescriptions Processed and payment sent back to Dispenser 1. Creates & signs Prescription 2. Patient Hands Prescription to Pharmacist (Maybe signed to claim exemption) 4. Prescriptions Batched and sent to the PPA

5. Problems with Present Practice • Fraud • Stolen Prescription Pads, Altered Dispensation Amounts • Data Integrity • Phone Call Clarification, Illegible Scripts • Administrative Workload • 578 million prescribed items in 2001 • Efficiency • 60% of Pharmacists believed that the introduction of electronic prescribing would lead to time savings (Kember Associates, 1999) • Patient Exemptions / Identification • Pharmacy Check

6. ETP Worldwide • Denmark • 35 per cent of prescriptions now sent electronically (Middleton,2000) • Germany • Electronic health card • USA • State ETP systems • UK • Hospital ETP systems and Pharmed trial

7. The Pilots and the Salford Model

8. Transcript Consortium Model

9. Transcript Model Perceived Benefits • Patient retains freedom of choice and has control over their own privacy • No reliance on a central database repository - therefore performance of system similar to present paper based system • Mirrors present system just reduces fraud and administrative workload for the PPA

10. Transcript Model Perceived Problems • Barcode Readers Complex and Expensive • Limit on size of prescription • Exemptions not automatic • Lost prescription requires GP callback • Barcode error rates

11. Pharmacy2U Consortium Model

12. Pharmacy2U Model Perceived Benefits • Patient may or may not have freedom of choice • Very low chance of lost prescriptions • No paper version of the prescription • May lead to advanced patient care

13. Pharmacy2U Model Perceived Problems • DIRECTED Prescriptions may lead to severe consequences for high street pharmacy • May be a problem with patient acceptance

14. Flexiscript Consortium Model

15. FlexiScript Model Perceived Benefits • GP And Pharmacy Applications Interface With Model Without The Need For Additional Hardware • Patient Retains Freedom of Choice

16. FlexiScript Model Perceived Problems • May be performance issues at the relay • Patient doesn‘t have complete control over their own privacy and lost script token requires GP callback • Prescriptions may be stored in the clear • Exemptions not automatic

17. University of Salford Model

18. University of Salford Model Perceived Benefits • Patient retains freedom of choice and has protection of their own privacy • Automatic Exemption and Authorisation Checking • In many ways mirrors present system (just electronically) • Only normal barcode scanners required at the pharmacy

19. University of Salford Model Perceived Problems • Lost prescription - requires GP call • Performance better than Flexiscript model since only encrypting once.(Research currently being undertaken to measure precise advantage)

20. Design Issues • Stakeholder Acceptance • Little change to procedures • Barcodes - Patient, GP, Pharmacist • Recovery procedures • Maintained freedom of choice for patient

21. Security Considerations • An Electronic Prescription Processing System must provide:- • Confidentiality > Encryption/Link Security • Secure Authentication > Digital Signatures • Secure Authorisation > Privilege Management Infrastructure • Integrity > Digital Signatures • Non-Repudiation of Origin > Digital Signatures

22. Security Model Comparison (1)

23. Security Model Comparison (2)

24. Present Status • An API designed to facilitate the introduction of our proposed electronic prescription processing system design has been built. Disparate applications can call our API to transfer prescriptions electronically • Described within the paper • Evaluation Phase • Qualitative Evaluation -Stakeholder Focus Groups • Quantitative Evaluation - Performance Research

25. The API • Three subsystems (Prescribing, Dispensing and PPA Operations) • Works in conjunction with two digitially signed supporting third party class structures • Security class structure • Directory configuration class structure

26. EPP Security Abstract Base Class Security Class Structure

27. Access Established Checks Authorisation Joe Bloggs Age 24 Directory Configuration class Logged in Security class Paracetamol Signature getPrescriptionEncryptionKey() getBarcodeKeyValue() API Operation - Example Prescribing Subsection PrescribingOperations class Prescription Store initialiseEPP (Security,Directory Config) setupPrescription(Patient details) addPrescriptionItem(Item details) Differin signAndStorePrescription() Prescriber application prints prescription

28. Further Information • For further research related to this project please visit • http:\\sec.isi.salford.ac.uk\

29. Questions