Australians are being warned about potential privacy issues with the new digital My Health Record system as the three month opt-out period begins.
People's medical records will be stored on a national database under the federal government scheme, to be viewed by patients, doctors and other medical staff at any time.
But lobby group Digital Rights Watch has expressed concerns about the security of My Health Record, and is urging everyone to opt out.
The opt out period starts on Monday, and ends on October 15.
"No guarantees have being given that individual citizen's personal information will be kept safe and secure," Digital Rights Watch chair Tim Singleton Norton said in a statement.
"Health information is incredibly attractive to scammers and criminal groups.
"There are also concerns of the current or future access being granted to private companies."
The government's Australian Digital Health Agency played down the security concerns.
"Patients control access to the record, so they can switch off their entire record and make it only available using a pin code, or use that process with individual documents," the agency's Dr Steve Hambleton told the ABC.
Opposition Leader Bill Shorten said the digital health record system was an important reform because it would lead to better health outcomes.
"But I don't blame people for being sceptical about this government in terms of the way it implements digital change programs," Mr Shorten told reporters in Tasmania on Monday.
"I say don't throw the baby out with the bath water, let's make this work, but I do accept this government have an ability to turn a lot of things into a mess when they touch them."
The National Rural Health Alliance said My Health Record would save lives in regional Australia, and urged people not to opt out.
"If you live outside a major city, you have less access to health services, and are more likely to delay getting medical treatment. That means you're more likely to end up being hospitalised," National Rural Health Alliance CEO Mark Diamond said in a statement.
"A My Health Record means that all your important health information is at the fingertips of your doctor, nurse or surgeon."