The basic functions needed for a secure eHealth application are:
To achieve a secure authentication of a person (whether health professional or patient) it is necessary to have a unique identifier. The person must then be registered in a database together with a certificate issued by a trusted body. This is a very important process and the work needed to create such a database is often underestimated.
In order to authorise a person to access applications or information, the cooperating organisations have to agree on a framework of rules on how a set of roles should be defined. This workload is also easily underestimated. An alternative to this type of general authorisation is to individually define how access should be allowed for each specific application. Authorisation can also be given by invitation for a specific application or occasion.
Privacy means that eHealth applications must be capable of handling patient consent. A piece of health-related information should not be allowed to be shared among health professionals outside the organisation from which the information originated without the patient consent. Many eHealth applications do not have this capability today and thus cannot be used for transnational cooperation without addressing specific considerations.
Integrity means that a piece of information must remain unchanged from source to receiver. This requires the use of electronic signatures connected to the person who is responsible for the set of information. Using this technology, the responsible person can be certain that the information she/he created is unchanged when it is seen by another person. Many eHealth systems used today do not offer this type of electronic signature.
Traceability means that all eHealth activities are logged, so that it is possible to find out subsequently which person has accessed health information related to a certain patient and when. Access to health information is only authorised when the use of the information is related to the care of the patient. It is not, however, feasible to lock in health information so that unauthorised access to health information is completely impossible. Access to information must therefore build on trust, that health professionals with access to patient information use the information only when needed for motivated medical purposes. The traceability will therefore constitute the possibility of retrospectively identifying possible abuse of health information. Many eHealth systems today do not offer sufficient traceability capability.