while doctors do need to work on drug research and development, the pew prescription project's allan coukellays other payments raise serious ethical concerns. >> there are a lot of doctors who are out there giving speeches which are essentially promotional. they are functioning as a marketing arm of the companies, and we just think that has the potential to influence prescribing and isn't consistent with evidence-based medicine that's guided by good science. >> reporter: of the $35 million pfizer paid doctors in the last six months of last year, $15 million went to research. $17 million to doctor speaking fees and consulting. about $2.5 million to meals and business travel. altogether, pfizer made payments to 4,500 doctors and health professionals. dr. freda lewis-hall, pfizer's chief medical officer, says the company needs to pay doctors to help develop new drugs. >> we're working to gain insights that we need, we're working to share information that's required. we're really looking to provide the best outcomes for our patients and it requires collaborations. these are absolutely essential