Oldham PCT has apologised for the loss of the data

The names, addresses and dates of birth of 148 patients were stored on two data memory sticks which have been misplaced, the PCT said.

All but three of the patients have been contacted so far and a formal investigation has got under way.

Gail Richards, Oldham PCT's chief executive, said: "We are deeply sorry, this should never have happened."

She added: "We have launched a full and thorough investigation and are reviewing our current policy relating to data storage.

"In the meantime, we have taken all the necessary steps to ensure that it cannot happen again."

Checks ordered

The PCT said its staff had offered to visit the people affected to reassure them that their care would not be affected.

A helpline has been set up for anyone with further questions or concerns.

NHS North West and the Department of Health have been informed.

Oldham PCT is not the first to admit losing patient records in recent months.

Eight trusts are reported to have lost 168,000 patient details in total.