A consultant neurologist whose work prompted the recall of thousands of patients kept his own records in private practice, his former clinic has said.
The Ulster Independent Clinic has sought advice on urgently obtaining access to the information required from files held by Dr Michael Watt to accurately identify any patients who may need to be contacted.
Its statement said: "We are acutely aware of the seriousness of this situation and the anxiety it is causing many patients and their families.
"As we focus on identifying those private patients who may need to be contacted in light of the concerns raised by the Royal College of Physicians report, we would like to reassure any of Dr Watt's patients, potentially impacted by this issue, that we are moving as quickly as possible to alleviate their concerns."
The Belfast Health and Social Care Trust has said it is "truly sorry" for having to recall 2,500 patients after a probe into the work of Dr Watt and a review of patient notes by the trust and the Royal College of Physicians.
The consultant is currently not treating patients but is still an employee, the trust said.
The Independent Clinic added: "Since this issue came to our attention, we have been liaising with the Belfast Health and Social Care Trust team to devise the best course of action to identify those patients impacted so as to avoid duplication or additional concern.
"Our early discussions with the trust have highlighted the complex and time-consuming nature of this process and we are currently examining the best way to expedite matters to enable us to communicate with the relevant patients in an appropriate manner and as quickly as possible.
"As an independent clinical practitioner who used the facilities at the Ulster Independent Clinic, Dr Watt retains his own patient records."