Three more hospitals have confirmed that they outsourced the transcription of medical reports to an outside firm.
However, none has reported any problem with the service.
Peamount Hospital in Dublin has become the latest hospital to confirm it uses the service.
In a statement to RTÉ News, Peamount said it has used the service since 2005, continues to use it and that it has encountered no problems.
The HSE's Galway University Hospital earlier confirmed that it outsourced the transcription of medical reports in 2004 to a company at the centre of a controversy over the unauthorised access and disclosure of patient medical records.
The hospital used the service for six months as a pilot project for the transcription of cardiology letters.
It says all material was encrypted and no patient identifiers were used.
Mercy University Hospital in Cork, a voluntary hospital, said it has been utilising the services of an online transcription company for the past six years.
It said it had no evidence whatsoever that any of its patient data has been misused, destroyed or disclosed improperly.
The hospital has been assured that the company's security system is intact and that there is no evidence of any systems failure.
Meanwhile, Tallaght Hospital said it has received 173 calls today to its helpline, which was set up after the controversy over possible breaches of patient confidentiality.
The hospital said the calls related to letters to GPs and not medical records.
The helpline number is 1800-283059 and is open from 9am to 5pm.
The Data Protection Commissioner has met with the private company, which Tallaght Hospital outsourced its reports to.
A spokesperson for the Commissioner said it was receiving full cooperation from the firm.
The Commissioner also said he will now be contacting the company's other clients but emphasised this does not imply that those clients necessarily suffered security breaches.
Yesterday, the hospital confirmed that patient medical records were the subject of unauthorised access and disclosure.
The hospital has used a private firm in the Philippines to transcribe medical reports and GPs' letters since 2004.
Gardaí and the Data Protection Commissioner are investigating the matter and are looking into how the sensitive information got into inappropriate hands.