IDAHO CODE ANN. § 39-1394 - Patient care records- retention- authentication under the health and safety law

Hospital records may be preserved in electronic medium, including microfilm.
 
Hospitals must retain clinical laboratory test records and reports for 5 years. X-ray film may be destroyed 5 years after exposure, or 5 years after the patient turns 18, whichever is later, provided that there is documentation that a physician has reach the x-ray films.
 
After the time period specified above, a hospital may destroy records by burning, shredding or by other method that ensures confidentiality of the information.
 
Hospital records containing information related to care, treatment, drug or pharmaceutical orders must be authenticated by the author or other practitioner that is responsible for the patient’s care. Authentication may be manual, by signature, or by unique electronic code.
 
Each hospital must have policies and procedures to assure timely and accurate authentication.