Devices the size of a grain of rice that are implanted with a needle could give emergency room doctors quick access to the records of chronically ill patients, the doctors group said in a report.

The association adopted a policy on Monday stating that the devices can improve the 'safety and efficiency of patient care' by helping to identify patients and enabling secure access to clinical information.

These radio frequency identification tags (RFIDs) are already used by Wal-Mart and other businesses to speed up their shipping systems by sending out small signals that can be scanned more easily than bar codes.

Implanting them in people 'can improve the continuity and coordination of care with resulting reductions in adverse drug events and other medical errors', said the report prepared by the association's ethics committee.

But the devices 'also may pose some physical risks, compromise patient privacy or present other social hazards'.

The main concern is protecting the privacy of the information on the devices.

There are also health concerns.

While the devices are removable and designed to stay in place, their small size could allow them to move to other parts of a person's body.

They may also cause interference with electrical devices like defibrillators, and it has not been determined what impact they may have on prescription drugs.

The report concluded that it is 'likely that utilisation of RFID devices for medical purposes will expand'.

The US Food and Drug Administration (FDA) has so far approved only 'passive' tags for human implantation. These cannot be altered once inserted and have a limited capacity and transmission range.

The devices are also allowed to only contain a unique identification code in order to protect patient privacy.

The FDA may eventually approve 'active' devices which contain internal batteries and can be updated as a patient's condition changes.

The association warned of 'potential social consequences' such as using the devices for surveillance, which could be an infringement on individual liberties.

It recommended that the devices not be implanted without the informed consent of patients and that doctors monitor their use.

AGENCE FRANCE-PRESSE