With a House vote expected on Thursday on legislation that would provide self-employed physicians an exemption from federal antitrust laws so they can bargain collectively with insurance companies, both sides are ramping up their lobbying efforts.

Opponents of the "Quality Health Care Coalition Act,'' led by the insurance and business communities, have taken to the

airwaves. The "Antitrust Coalition for Consumer Choice in Health Care,'' an umbrella organization, is running advertisements on Washington area radio stations claiming the bill would allow doctors to raise fees at will, much as the Organization of Petroleum Exporting Countries (OPEC) has successfully raised gasoline prices. "Doctors' incomes will rise 15 percent on average, because doctors' cartels will be free to price-fix and boycott,'' says the ad.

Consumers would feel pain almost immediately, claims the Blue Cross and Blue Shield Association in a letter to members of Congress. "For example, an early target of collective bargaining is likely to be the health plan provision that protects

consumers from balance billing,'' wrote BCBSA Senior Vice President Mary Nell Lehnhard, referring to the practice of allowing doctors to charge patients the difference between their regular fees and what the insurance company will pay.

Medicare has limited the amount physicians can balance bill since 1989. "Just as it is important for Congress to protect

Medicare beneficiaries against balance billing, the private sector should be able to do the same,'' she wrote.

For its part, the American Medical Association (AMA) is keeping its lobbying less public. "We think reasoned discussion with

our Representatives is the American way, not scare tactics with ads,'' said Dr. Donald Palmisano, the AMA trustee who is

leading the organization's efforts on the measure.

Palmisano noted that at least for the moment, the AMA's efforts appear to be working. "We have over 220 cosponsors,'' he said, two more than the 218 needed to pass a bill in the House. "This bill's going to pass the House and the momentum's going to carry it into the Senate and the President is going to sign it,'' he predicted. So far, though, the measure has no sponsor in the Senate and Clinton administration officials have argued for its defeat.