Understanding medical research Thomas Abraham. Health reporting is often about life and death Experts are often divided There are often commercial, political.

Understanding medical research

Thomas Abraham

Health reporting is often about life and death

Experts are often divided There are often commercial, political

and personal interests at play The public depend on you for

information on which they can act

Three areas of health and medical reporting

Health policyMedicine Public health

Medical Reporting

By the end of this class, you should Know the different sources of medical

news Be familiar with the main medical

journals Know the different categories of

medical research studies Have an understanding of how to turn

a study into news

Where does medical news come from?

1. Medical journals

2. Scientific conferences3. Press conferences to announce findings4. Reports from organizations like the WHO

Journal articles are regarded as the most reliable source, because the findings have been peer reviewed

The most prestigious:The LancetThe New England Journal of Medicine (NEJM)British Medical Journal (BMJ)Journal of the American Medical Association (JAMA)ScienceNature

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 review

Peer review=other experts in the field review the paper and asses it

Peer 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)

The structure of a journal article-IMRAD

Abstract: sums up study Introduction- Why is this study being

done?Methods- How did you do it?Results- What did you find?Discussion- What is its importance?

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?

Types of studies

1. Observational (observe groups of people, gather data, but does not make any kind of intervention)

2. Experimental studies ( makes an intervention)

3. Meta studies: takes data from a large number of studies and compares them, providing results that are stronger than individual studies

Observational studies

1. Descriptive studiesTypically cross sectional studies

( measures or surveys data at a point in time)

Eg: Opinion survey of nurses in Hong Kong about H1N1 vaccination

Eg: Prevalence of obesity among teenagers

Describes a situation at a point of time, but does not analyse cause and effect

Observational studies

2) 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

Doll and Bradford Hill’s 1950 study

Two groups of patients admitted to London hospitals were studied

649 lung cancer patients( cases) 649 patients without cancer (controls) Cases and controls matched for age, sex Aim of the study: “whether patients with

carcinoma of the lung differed materially from other persons in respect of their smoking habits”

649lung

cancer

649no lung cancer

Question to be answered: is smoking the difference between these two groups?

Cases Controls

649lung

cancer

649 no lung cancer

642Smokers(99.7%)

622Smokers(95.8%)

Cases Controls

649lung

cancer

649 no lung cancer

2 Non Smokers(0.3%)

27 Smokers(4.2%)

Cases Controls

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”

Some weaknesses of case control studies

Relies on past exposure – therefore often relies on memory, can lead to biases in data

Observational studies

Analytical studiesb) Cohort studies- Two or more groups of

people are chosen on the basis of differences in their exposure to a particular agent and followed up over a period of time to see the differences in outcome between the groups

http://www.framinghamheartstudy.org/

Doll and Bradford Hill’s study Studied 40,000 British doctors over 10, 20

and 40 years Divided them into 4 groups non smokers,

light, moderate and heavy smokers Results showed substantial differences in

lung cancer mortality between smokers and non smokers

Showed heavier smokers had a greater chance of developing cancer than the other groups ( dose response relationship)

Some limitations of cohort studies

Can take a long time People can drop out Not an absolute proof of causation

Experimental studies- Randomised controlled trial (RCT)

Gold standard of causality Used to evaluate new treatments Subjects are randomly allocated to

intervention (gets new treatment and control( does not get new treatment) groups

Both groups should be as similar as possible

Double blind= neither subject nor researchers know who is getting what

Meta Studies

Looks the results of a wide range of published studies; regarded as high evidence value

Evaluating studies

Is 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 people What will it cost? Conflicts of interest

How big were the numbers tested? How relevant are the findings-is it of

immediate benefit for people What will it cost? Conflicts of interest

Resources

Press releaseswww.eurekalert.org How to read a paperhttp://www.bmj.com/cgi/content/full/315/7102/243 BMJ press releaseshttp://group.bmj.com/group/media/latest-newsJAMA press releases:http://pubs.ama-assn.org/media/pastreleases.dtlScience Media Centre http://www.sciencemediacentre.org/pages/press_releases

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

Writing

What’s the lead? What additional material do you need? What do you need to explain?

http://abcnews.go.com/Health/wireStory/oral-cancer-virus-affects-percent-americans-15446897#.TydBS8VOBuq

http://www.mclph.umn.edu/watersedge/play.html

Deadlines

Feb 28: First Story March 15: Book Review March 28: Second Story April 17: Third StoryOnline courses to be completed by Feb 21 HIV/AIDS Feb 28: Malaria March 13: TB