Refers to the integrity and reliability of the information system.                   
 System failure
 Hardware failures
 Software bugs
 Viruses
 Hacking attack
If the system security is not robust enough, problem such as system failure, corrupted information, information alteration, loss of information and information theft will happens.
The consequences of such events can be minor such as unavailability of services due to down times to more serious repercussion such as doctor making wrong diagnosis due to corrupted information.
Therefore system security should not be look upon lightly.
Basically, a good electronic health information system should:
 Take into account system security needs in the initial design of the
system.
 Have appropriate backup - to protect against loss of image
inventory in the event of accidents. For example, Tan Tock Seng
Hospital has a 24 terabytes off-side storage system.
 Have adequate backup power supply
 Have Inbulit security mechanisms such as
- Encrytion
- Firewall
- Intrusion detection system
- Anti-virus capability and so on
 
 
