CHAPTER 8. DATA SECURITY AND PRIVACY
F.ALLAERT & O.FERRER-ROCA
EU Directive for processing personell data and controling its
movement was covered in directive 95/46/EC as a model for the
" new data protection regime " to be stablish in
practice through national legislations by 24 October 1998 at the
latest ( Art 32 ). In fact this directive defines " data
privacy " for the EU for the next few years .
Issues relating manual Medical Records or other personal data
filling systems have an extended period of 6 years intill October
2007.
Sensitive Personal Health Data is recognized in Art.8 ( special
categories of data ) and have two premises:
- Confidentiality ( recognized since Hippocrates )
- Integrity and availability
CONFIDENTIALITY is defined as : the property which assures that only authorized users in normal conditions can have access to the system.Violations can be found in
Theft ( all or part of the system )
Manipulating ( assure origin and reception )
Unauthorized access
Falsifiyng user identity
Making unauthorized copies
Intercepting messages ...
Standards in Health Data Handling are regulated by the Standard Body of Medical Informatics ( CEN Technical Committee 251- working group 6 ) that classify Health Information Systems ( HIS ) in terms of requirements on
1.- SECURITY
Art.17 stablished that is mandatory the appropiate
- TECHNICAL and
- ORGANIZATIONAL
measures to protect personel data as soon as National
Legislation become effective, particularly if data is transmited
over a network .
Those measures include:
It includes :
2.- RECTIFICATION, ERASURE and BLOCKING
In art. 12b. A digital signature for any modification , data and
time of all messages as well as backups on a non-erasble
recording device certify by a third party is part of the task.
3.- THIRD PARTY DISCLOSURES
To rectify, erased or blocked data it is required that the "
controller " notifies Third Parties.
A Third Party Disclosure Register is required to be recognized in
the system audit trail.
This register should be kept as part of the patient record.
4.- USER AUTHENTICATION
Users should be properly authorized and authenticated
Freely share passwords with colleges must be prohibited when the
system become an integral part of the delivery of Health Care.
Authentication of system users is particularly important and will
require Third Parties to give access to HIS , particularly if
delivery care invovled multiprofessional teams, shared care
between hospitals, community care providers and GP s ( general
practitionaires ).
5.- DATA ORIGIN AND CONSENTS
Origin of personal data is covered in Art 10 and 11, and the
consents of usage on articles 7 and 8.
On this point a clear idea of the Encryptation techniques as well
as of the digital signature is required.
ENCRYPTATION
Cryptography means in grek strange ( cryptos ) writting (
graphos ) and is the science that tries to make documents
understandable for those we shoose and unintelligible for the
rest.
The procedures to obtain a cryptography are studied in the Cryptoanalysis
, that use mathematics and particularly the number theory ( prime
numbers ).
The result to apply this technique is that a plaintext is
transformed into a ciphertext by a process of encoding or
ciphering. Since process should be by definition reversible it is
base on pair keys: A computerized encoding algorith is use
for ciphering ( in general PUBLIC KEY ) and a related decoding
algorith for deciphering ( in general a PRIVATE KEY, secret and
personal ). Both keys are interchangable.
Advantages : Identify any altered information with precision
Problems : time consuming
Cryptographic procedures can basically be of two types :
Key Certificates for authentication can be obtain
DIGITAL SIGNATURE
In general the PUBLIC ( encryption ) and PRIVATE ( decription )
keys are inverted.
The private key is used for cyphering linking your identity to
the document as an electronic signature.
Plus this basic scheme other functions are link to a electronic
digital systems are :
Part or total reproduction not allow without permission
Revisado: jueves, 05 junio 1997.
Con el soporte informático y de comunicaciones
del CICEI, Universidad
de Las Palmas de Gran Canaria