2 Three areas of health and medical reporting MedicinePublic healthHealth policy
3 Medical Reporting By the end of this class, you should Know the different sources of medical newsBe familiar with the main medical journalsKnow the different categories of medical research studiesHave an understanding of how to turn a study into news
4 Where does medical news come from? Medical journalsScientific conferencesPress conferences to announce findingsReports from organizations like the WHO
5 Journal articles are regarded as the most reliable source, because the findings have been peer reviewedThe most prestigious:The LancetThe New England Journal of Medicine (NEJM)British Medical Journal (BMJ)Journal of the American Medical Association (JAMA)ScienceNature
7 How do journals work?Researchers write up their findings in a paper and submit to a journal, which then puts it through a process of peer reviewPeer review=other experts in the field review the paper and asses itPeer review is not perfect, but there is not a better system at present (the case of Hwang Woo-suk and the cloning of human stem cells)
8 The structure of a journal article-IMRAD Abstract: sums up studyIntroduction- Why is this study being done?Methods- How did you do it?Results- What did you find?Discussion- What is its importance?
9 What reporters need to ask Is this news?How solid is the study and the evidence?Will people be able to use, or benefit from this study?Who funded the research?
10 Types of studyObservationalExperimentalMeta studies
11 Types of studiesObservational : Where researchers observe groups of people, gathers data, but do not make any kind of interventioneg: a study of pollution on respiratory disease which observes people in a polluted part of town, measures surrounding air pollution, and looks at the incidence of disease in this group.
12 Experimental: Where the researchers intervene in some way, for example by providing a new treatment, and then measures the results, and compares with an older treatment.
13 Metastudy: Looks at a large number of published studies on a particular topic, and looks at the overall conclusion
14 Different studies answer different questions Experimental studies, such as clinical trials are best suited to answer questions of cause and effect ( including is the effect of drug A better than drug B)Observational studies tend to show statistical associations, rather than cause and effect.
16 Observational studies Cross sectional studies measure, or survey data at a point in time)Eg: Opinion survey of nurses in Hong Kong about H1N1 vaccinationEg: Prevalence of obesity among teenagersThey describe a situation at a point of time, but does not analyse cause and effect
17 Observational studies Analytical studies (seek to suggest possible reasons for occurrence of a disease or population)a) Case control studies-Patients with a particular disease or condition are matched with a similar group of people without the disease, and then data is collected from both groups about past exposure or behaviour
18 Bradford Hill and Doll’s 1950 study Two groups of patients admitted to London hospitals were studied649 lung cancer patients( cases)649 patients without cancer (controls)Cases and controls matched for age, sexAim of the study: “whether patients with carcinoma of the lung differed materially from other persons in respect of their smoking habits”
19 CasesControls649no lung cancer649lung cancerQuestion to be answered: is smoking thedifference between these two groups?
24 Proportion of heavy smokers greater in cancer patients Proportion of lighter smokers lessConclusion: “it must be concluded that there is a real association between carcinoma of the lung and smoking”
25 Some weaknesses of case control studies Relies on past or behaviour – therefore often relies on memory, can lead to biases in data
26 Observational studies Cohort studies- Two or more groups of people are chosen on the basis of differences in their behaviour, or exposure to a particular agent and followed up over a period of time to see the differences in outcome between the groups
27 Doll and Bradford Hill’s study Studied 40,000 British doctors over 10, 20 and 40 yearsDivided them into 4 groups non smokers, light, moderate and heavy smokersResults showed substantial differences in lung cancer mortality between smokers and non smokersShowed heavier smokers had a greater chance of developing cancer than the other groups ( dose response relationship)
28 Some limitations of cohort studies Can take a long timePeople can drop outNot an absolute proof of causation
29 Experimental studies- Randomised controlled trial (RCT) Gold standard of causalityUsed to evaluate new treatmentsSubjects are randomly allocated to intervention (gets new treatment and control( does not get new treatment) groupsBoth groups should be as similar as possibleDouble blind= neither subject nor researchers know who is getting what
30 Meta StudiesLooks the results of a wide range of published studies; regarded as high evidence value
31 Evaluating papersIs it still at the animal or laboratory stage, or human stage?Where published? peer reviewed journal, scientific meeting or press release/conference?How big were the numbers tested?How relevant are the findings-is it of immediate benefit for peopleWhat will it cost?Conflicts of interest
32 How big were the numbers tested? How relevant are the findings-is it of immediate benefit for peopleWhat will it cost?
33 Exercise Read the article Is it newsworthy? Is it a good study ( ie large numbers, well designed)?Published in a peer reviewed journal?Will this information benefit patients?If it is a new treatment, what cost?Conflicts of interest
34 Writing What’s the lead? What additional material do you need? What do you need to explain?
35 Deadlines Feb 28: First Story March 15: Book Review March 28: Second StoryApril 17: Third StoryOnline courses to be completed byFeb 21 MalariaFeb 28: TBMarch 8: HIV