Four major companies have made voluntary disclosures about payments to doctors, hospitals and other medical professionals under pressure for more openness about the practice, the Associated Press reports. Critics say such payments can influence doctors'' decisions about drugs and other treatments. Drugmakers will be required to make such disclosures in 2013 for payments made in 2012 under the health overhaul law that President Barack Obama signed last week. Pfizer Inc. said Wednesday that it gave doctors and teaching hospitals a total of $34 million in the last half of 2009 for services ranging from speaking to other doctors about the company''s products to running studies of its experimental drugs. GlaxoSmithKline PLC in February 2009 posted fourth-quarter 2008 grants and contributions to hospitals and other health care organizations, then began posting quarterly payments to physicians for speaking to other doctors and for consulting services, starting with the second quarter of 2009. Eli Lilly & Co. began disclosing how much money it paid to individual doctors for advice, speeches and other services on July 31, 2009. It reports payments exceeding $500 every quarter. Merck & Co. announced in February that it paid doctors and nurses a total of $9.4 million in the third and fourth quarters of 2009 to give talks to colleagues about the drugmaker''s products and other health topics. Johnson & Johnson, the world''s biggest maker of health care products with more than $60 billion in annual revenue, has said its pharmaceutical business will begin reporting physician payments in the first half of this year. That will later expand to include its medical devices and diagnostics unit.