Some Missouri lawmakers are supporting a bill to stop doctors from marking up the cost of procedures like skin biopsies and mammograms performed by outside laboratories.

The law would prohibit pass-through billing, in which a doctor sends a patient's test to an outside laboratory. After the lab charges the doctor, the doctor bills the patient at a higher cost and keeps the extra money as profit.

Republican House member Kevin Wilson of Neosho says the state should protect patients from doctors who charge for work they don't actually do.

Opponents argue that the state shouldn't get involved in pricing decisions that should be left to private-practice physicians.

The bill has been approved by the Senate and is awaiting debate in the House.