summer-2003-Part 2-live - Nieman Foundation - Harvard University

Medical ReportingHelping Reporters Play the Medical Numbers GameA journalist reminds us about how tricky putting ‘facts’ into perspective can be.By Lewis CopeAs medical reporters, we laugh atthe tale about the drug-treatmentresearcher who said, “Thirtythreepercent were cured, 33 percentdied—and the third mouse got away.”We know that the more patients (ormice) in a study, the better. Big numbershelp make a study’s findings “statisticallysignificant.” This term simplymeans it’s unlikely that the study’s keystatistical findings are due to chancealone. But merely obtaining statisticalsignificance doesn’t prove that thestudy’s conclusions are medically significantor correct. So, as reporters, wemust probe further and be alert for thenumbers games and other things thatmight lead us awry.Two journalistic instincts—healthyskepticism and good questioning—come in handy on the medical beat.And, if you don’t report in this area, apeek into what we do will make you amore astute consumer of medicalnews—and a more careful viewer ofmedical claims on the Internet.Hints About MedicalCoverageWhat follows are thoughts I have aboutthings that scientists and reporters mustconsider.Remember the rooster who thoughtthat his crowing made the sun rise?Even with impressive numbers, associationdoesn’t prove causation. A virusfound in a patient’s body might bean innocent bystander, rather than thecause of the illness. A chemical in atown’s water supply might not havecaused illnesses there, either. Morestudy and laboratory work are necessaryto certify cause-and-effect links.Let me cite one current case in whichprecisely this caution is needed. Newsreports have speculated about whethersome childhood immunizations mightbe triggering many cases of autism. Asa reporter, this has the sound of coincidence,not causation. Autism tendsto appear in children about the timethey get a lot of their vaccines. Is additionalstudy warranted? Probably. Butthere is concern that in the meantimeparents will delay having children immunizedagainst measles and otherdangerous diseases. In a lot of thepress reports, the missing figures arethe tolls these childhood diseases tookbefore vaccines were available.Always take care in reporting claimsof cures. The snake-oil salesman said,“You can suffer from the common coldfor seven days, or take my drug and getwell in one week.” Patients with someother illness might be improving simplybecause their disease has run itsnatural course, not because of the experimentaldrug they’re taking. Care isneeded to sort claims made about whathas cured a particular ailment.In covering stories about diseaseoutbreaks and patterns, be cautiousabout case numbers. There was a storyrecently about how Lyme disease caseshave soared in some states. The articlecited statistics, but buried some importantcautions. Improved diagnosis andreporting of Lyme cases might be behindmuch of this increase. The journalisticantidote: Refer to such numbersas reported cases and explain whyyou are doing so.Sort through when you might bedealing with the power of suggestion.A large federal study examining qualityof life issues recently concluded thathormone therapy for menopausedoesn’t benefit women in many of theways long taken for granted. How couldso many women, for so long, haveconcluded that the hormone therapymade them more energetic and lessdepressed? A patient who wants andexpects to see a drug work may mistakenlyattribute all good feelings to themedication.The “gold standard” of clinical researchis a double-blind, placebo-controlledstudy, with patients randomlyassigned to either a treatment group orto a comparison (no treatment) group.Blinding means that, until the study iscompleted, neither the researchers northe patients know who is getting theexperimental treatment and who isgetting only a placebo. This keeps expectationsand hopes from coloringreported results. Less rigorous studiesstill might be important, but findingsfrom them require more questioningby journalists. When their findings arereported as news, the absence of the“gold standard” should be stated.Side effects are a big part of medicalcoverage and need to be handled properly.Some drugs have been taken offthe market after serious side effectswere discovered, long after the originalstudies found no problems. A seriousside effect that strikes only one inevery 10,000 patients might have beenmissed in the original studies involvinga few thousand patients. The problembecomes apparent only after the drugis marketed and then taken by more64 Nieman Reports / Summer 2003