Scottish government plans allowing more than 100 public bodies to access personal data through an individual’s NHS number will be debated by MSPs.
Opponents said the move amounted to identity cards by the “back door”.
The plan would see organisations such as HMRC and Scottish Canals being able to see certain data on the NHS Central Register (NHSCR).
A consultation on the issue closed last week and the Scottish government has promised to “listen to all concerns”.
Everyone born in Scotland or registered with a GP north of the border has a Unique Citizen Reference number held in the NHSCR.
The Scottish government said opening up access to NHSCR would have a number of advantages, such as helping to trace children missing from education, identifying foreign patients accessing the NHS, allowing people to access public services securely, and helping HMRC to complete the tax register.
It added that “only a limited amount of data would be shared” and medical records would not be part of the register.
However, opponents have warned there could be a risk of a massive data breach.
Critics have also questioned why the data should be shared with more than 100 public bodies, including Scottish Canals and Quality Meat Scotland.
The proposals would amend existing legislation and could therefore be approved by a Holyrood committee, known as a “negative instrument”.
Scottish Liberal Democrat leader Willie Rennie has tabled a motion calling for full parliamentary scrutiny of what has been described as a “super ID database”.
Speaking ahead of the debate, he said: “I will make no bones about reaching out to all political parties to support our motion. When it comes to fundamental issues of protecting our civil liberties and building a fairer society, there can be no party line.
“The SNP joined us in 2005 to oppose the creation of ID cards. The Conservatives supported our efforts to repeal the legislation. And Scottish Labour have supported our motion against this proposal.
“If SNP ministers took their eye off the ball whilst the civil service created these proposals, now is the time to speak out against them.”
Scottish Conservative MSP Liz Smith said there were concerns about individual consent.
She said: “This is about introducing ID cards by the back door.
“The fact that consent has been removed from this plan is particularly worrying.
“And it cannot be right that, under the current plans, it has not been scrutinised properly by parliament.”
Deputy First Minister John Swinney said personal privacy would be protected and restated the Scottish government’s opposition to ID cards.
He said: “We are not and we will not create a new database.
“We will not be sharing health records.
“We will listen carefully to all consultation responses.
“And we will act in a manner that is consistent with our long-standing principles in protecting personal data.”
He added: “Decisions will only be taken after full scrutiny by Parliament of any eventual proposals. That is the principle upon which our government is run and will remain so.”