Moriarty et al. (2010) tried to answer this question by studying the 2003 cancer coverage in 44 major American newspapers (they started with 50, but had difficulties obtaining full-text coverage for six of them). Their final sample included 3,656 in-depth cancer articles that were coded for topics, aspects of cancer continuum (prevention, treatment, etc.), sources and clinical trials.
The most frequently cited sources were research institutions (29.73%), followed by medical journals (12.30%), ACS (9.57%) and NCI (4.54%).
Ten most cited sources:
- New England Journal of Medicine
- Journal of the National Cancer Institute
- Journal of the American Medical Association
- Johns Hopkins University
- Memorial Sloan Kettering Cancer Center
- Fred Hutchinson Cancer Center
- Harvard University
- H. Lee Moffitt Cancer Center
Sources and story type
The most popular subjects were personal profiles of people with cancer, cancer research and cancer fundraisers/benefits. Research institutions were the most popular sources in almost every story type. In comparison, medical journals were mostly cited in cancer research stories. Pharmaceutical companies were rarely cited, and when they were, it was mostly in reports of cancer research and stocks.
Sources and the cancer continuum
Treatment was the most mentioned aspect of the cancer continuum (in nearly 75% of the articles). Detection was mentioned in about half of the articles. Of all aspects, prevention was the least likely to appear in stories.
Clinical trials and their tone
Out of the 317 stories about clinical trials, more than half (53.6%) cited a research institution. Medical journals were also cited frequently. The general tone of clinical trials coverage was optimistic (more than half the stories) with most of the other stories having a neutral or balanced tone. Articles that cited medical journals or pharmaceutical companies were significally more likely to be optimistic.
Overall, sources in cancer coverage change according to the type of the story. The ACS, for example, was frequently cited in awareness/education stories. Research articles frequently cited medical journals. The most interesting finding is that pharmaceutical companies aren't a main source for cancer stories (it could be, however, that those companies funded the research reported. The paper didn't look into funding sources). The authors mention that it's possible the reason for the large amounts of research institutions mentions is that the reporters rely on said institutions press releases.
Moriarty, C., Jensen, J., & Stryker, J. (2009). Frequently cited sources in cancer news coverage: a content analysis examining the relationship between cancer news content and source citation Cancer Causes & Control, 21 (1), 41-49 DOI: 10.1007/s10552-009-9432-x