Hundreds of articles in medical journals claiming to be written by academics or doctors have been penned by ghostwriters in the pay of drug companies, an Observer inquiry reveals. The journals, bibles of the profession, have huge influence on which drugs doctors prescribe and the treatment hospitals provide. But The Observer has uncovered evidence that many articles written by so-called independent academics may have been penned by writers working for agencies which receive huge sums from drug companies to plug their products. Estimates suggest that almost half of all articles published in journals are by ghostwriters. While doctors who have put their names to the papers can be paid handsomely for 'lending' their reputations, the ghostwriters remain hidden. In the United States a legal case brought against drug firm Pfizer turned up internal company documents showing that it employed a New York medical writing agency. One document analyses articles about the anti-depressant Zoloft. Some of the articles lacked only one thing: a doctor's name. In the margin the agency had put the initials TBD, which Healy assumes means 'to be determined'. Dr Richard Smith, editor of the British Journal of Medicine, admitted ghostwriting was a 'very big problem'. 'We are being hoodwinked by the drug companies. The articles come in with doctors' names on them and we often find some of them have little or no idea about what they have written,' he said.