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Covering Screening Tests: Do No Harm (As A Reporter)

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One of two talks I gave at Cancer Research in the Media: The NCI’s 2nd Annual Inter-American Workshop for Scientific Journalism

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Covering Screening Tests: Do No Harm (As A Reporter)

  1. 1. Covering Screening Tests: Do No Harm (as a Reporter) Ivan Oransky, MD Executive Editor, Reuters Health Cancer Research in the Media Inter-American Workshop for Scientific Journalism Guadalajara, Mexico November 7, 2011
  2. 2. What’s Not Worth Covering
  3. 3. What’s Worth Covering? <ul><li>Focus on evidence, not opinion, advocacy, or anecdote </li></ul><ul><li>Criteria: Peer-reviewed? </li></ul><ul><li>Most journals are </li></ul><ul><li>Most conferences aren’t </li></ul>
  4. 4. What’s Worth Covering?
  5. 5. What’s Worth Covering? <ul><li>Conferences select presenters based on < 1000 words </li></ul><ul><li>Urologists at U of Florida & Indiana U studied 126 randomized controlled trials presented in 2002-2003 </li></ul>
  6. 6. What’s Worth Covering? <ul><li>RCTs are the “gold standard” of medical evidence </li></ul><ul><li>But the quality of that evidence wasn’t pretty </li></ul><ul><li>No abstract said how trial subjects were randomly assigned to different treatments or placebos </li></ul><ul><li>None told how the study ensured that neither the researchers nor their doctors knew which they got </li></ul><ul><li>Only about a quarter said how long researchers followed the subjects in the trial </li></ul>
  7. 7. What’s Worth Covering? <ul><li>Published? </li></ul><ul><ul><li>In what kind of journal? </li></ul></ul><ul><ul><li>How highly ranked (e.g., what impact factor)? </li></ul></ul><ul><ul><li>Just because it’s in a journal doesn’t mean it’s the highest-level of evidence </li></ul></ul>
  8. 8. From Covering Medical Research , Schwitzer/AHCJ
  9. 9. Journals: What to Keep in Mind <ul><li>Positive publication bias: </li></ul><ul><ul><li>Publish a trial that will bring US$100,000 of profit or meet the end-of-year budget by firing an editor. -- Former BMJ editor Richard Smith </li></ul></ul><ul><li>Over-reliance on embargoed studies </li></ul><ul><li>How often it turns out to be wrong </li></ul>
  10. 10. Journals: What to Keep in Mind Ioannidis JPA. PLoS Med 2005; 2(8): e124
  11. 11. Journals: What to Keep in Mind
  12. 12. Always Read the Study <ul><li>Writing about a study after reading just a press release or an abstract – without reading the entire paper – is journalistic malpractice </li></ul>
  13. 13. How to Get Studies <ul><li> for embargoed material </li></ul><ul><li>Join the Association of Health Care Journalists – membership includes access to Cochrane Library, Health Affairs, JAMA, and many other journals </li></ul><ul><li>ScienceDirect (Elsevier) gives reporters free access to hundreds of journals </li></ul><ul><li>Open access journals (e.g., Public Library of Science ) </li></ul><ul><li>Ask press officers, or the authors </li></ul>
  14. 14. A Dirty Little Secret <ul><li>Keep a biostatistician in your back pocket </li></ul>Photo by Peyri Herrera, on Flickr
  15. 15. How to Cover Screening <ul><li>Early detection is only worthwhile if two conditions are met: </li></ul><ul><ul><li>the disease tends to kill people (not all do) </li></ul></ul><ul><ul><li>there are effective treatments that people are willing to have </li></ul></ul><ul><li>Keep lead time bias in mind </li></ul><ul><li>Be wary of “pre-cancerous” conditions </li></ul><ul><li>Remember: Screening tests have harms </li></ul>
  16. 16. Testing vs Screening <ul><li>If someone is part of a risk group, that’s testing, not screening </li></ul><ul><li>Screening refers to testing large populations without any clear increased risk </li></ul>
  17. 17. Are There Alternatives? <ul><li>Colonoscopy vs. sigmoidoscopy vs. fecal occult blood testing </li></ul><ul><li>Digital mammography vs. film mammography </li></ul>Brownlee S, Lenzer J. The New York Times, 10/5/2011
  18. 18. What If You Test Positive? <ul><li>Is there a good treatment? </li></ul><ul><li>What are side effects and costs of treatment? </li></ul>
  19. 19. What Do Guidelines Say? <ul><li>USPSTF </li></ul>
  20. 20. What Do Guidelines Say? <ul><li>Cochrane Library </li></ul>
  21. 21. What Do Guidelines Say? <ul><li>Cochrane Library </li></ul><ul><li>Scientific and medical societies </li></ul>
  22. 22. Who Gains from Promoting Screening? <ul><li>Doctors, hospitals </li></ul><ul><li>Drug and device manufacturers </li></ul><ul><li>Advocacy groups </li></ul><ul><ul><li>More worry, more funding </li></ul></ul><ul><li>Are you engaging in disease mongering? </li></ul>
  23. 23. Number Needed to Screen <ul><li>An elegant way to help decide whether something is worthwhile </li></ul><ul><li>Example: </li></ul><ul><li>To find one dangerous breast cancer, you’d need to screen 1,900 women between 40 and 50, compared to 1,300 women over 50. </li></ul><ul><li>So how many false positives, biopsies, overdiagnosed/overtreated women would result? </li></ul>
  24. 24. Number Needed to Screen <ul><li>“ Most women with screen-detected breast cancer have not had their life saved by screening. They are instead either diagnosed early (with no effect on their mortality) or overdiagnosed.” </li></ul>
  25. 25. Acknowledgement/Contact <ul><li>Nancy Lapid, Reuters Health </li></ul><ul><li>[email_address] </li></ul><ul><li>Twitter: @ivanoransky </li></ul>