The Nurse On Call recruitment agency said in a statement yesterday that the nurse at the centre of the Naas hospital allegations had worked for it.
The agency had placed the nurse in the hospital during the period under investigation, it also confirmed - the nurse at the centre of the Garda investigation has denied there were discrepancies in administering drugs to patients at the hospital.
The well-known agency, which has placed nurses in short and long-term contracts in the Republic since 1981, said the nurse first applied for work on July 31st, 2002.
"At that time she was in full-time employment in a Dublin hospital. She subsequently worked part-time (during time off) from August to November 2002.
"She left her full-time employment at the end of November 2002. Up to January 2003 she worked at Naas General Hospital and three other hospitals/clients for short periods. Since 21st January, 2003, she has worked solely at Naas hospital."
The agency's director, Ms Catherine Kennedy-Arnold, told The Irish Times that all its requirements for registration had been met in this case.
The files on the nurse under investigation had been forwarded to the Garda and the South-Western Area Health Board, she said. "We would like to assure the public that strict vetting procedures are in place in regard to any nurse joining our agency." These include current registration with An Bord Altranais, two references from previous employers, proof of indemnity insurance and Garda clearance.
The Irish Times has seen the application form used by Nurse On Call when recruiting nurses.
It includes questions about the applicant's state of health and has a check list outlining whether references have been received with an assessment of the quality of the reference supplied.
Nursing agencies are used frequently by hospitals to provide cover for nurses on leave or in cases where it has not be possible to fill permanent posts.
In the case of Nurse On Call, 75 per cent of its nurses are in full time or job-sharing employment elsewhere and work with the agency on their days off.