The Science of Cancer Prevention

8/20/2019 The Science of Cancer Prevention

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The Science of Cancer Prevention:Where Do Journalists Fit In?

Barry Kramer, MD, MPH,

Director, NCI Division of Cancer Prevention

January 2016


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Disclosure Information

I have no financial relationships to

disclose.

Opinions are mine, not official positions

of the U.S. federal government or

ational Institutes of !ealth.


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Alarmism in Science

Scientists

ma"e

meaningless

or am#iguous

statements.

$he media

translates

statements into

alarmistdeclarations%oliticiansrespond to

alarm #y feeding

scientist more

money


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Important Roles of Journalists

&ct as #ridge and gate"eeper to the pu#lic' (hat)sreally valid and useful*

Serve as honest #ro"ers of ne+ information for the

pu#lic

onvey the strength of the evidence

Understand strengths and limitations of study designs

-eport ne+ findings in the contet of eisting

"no+ledge


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$he press, on its o+n, if it chooses, can ma"e

the transition from cheerleaders of science to

independent o#servers/ $he ournalistic

trumpeting of medical cures on the #asis of

+isps of evidence, even though accompanied #y

so#er cautions against optimism, deserves to #eseverely throttled #ac", in recognition of an

unfortunate reality' $hough ne+s is sold around

the cloc", maor advances in medicine come

along infreuently.

Daniel Greener!" Science, Money, and Politics" #$$%


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&

It is difficult to ma"e healthy people

#etter off than they already are.

Core Issues in Screenin! an'

Prevention

Strong evidence of #enefit is

important +hen putting large

num#ers of healthy people in harm)s

+ay.


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)evels of Decision *a+in!)evel I: “Would you have this done for yourself or for someone

else in your immediate family?”

Influence' , one-s personal e.perience /ith the 'iseasean' capacit, to 'eal /ith ris+0

Affects fe/ people0

)evel II: “What would I recommend to my patient/client?”

Ph,sician ma+in! a recommen'ation for his1herpatients0 Influence' , prior e.perience" ut thescientific evi'ence ma, pla, a !reater role0

Affects possil, hun're's of people0

)evel III: “What would I recommend to the nation, the

world?” Across2the2oar' recommen'ations for apopulation0 *ust e ase' on ri!orousassessment of the scientific evi'ence0

Affects hun're's of thousan's" even millionsof people0


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3astian" Scientific American lo!

*arch #4" #$%5


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7uestions to As+ Aout *e'ical Research

%0 What is the e.posure an' /hat is theoutcome?

#0 8o/ certain is it that e.posure causes

outcome?40 8o/ important is the outcome?

50 8o/ i! is the effect?

90 To /hom 'oes it appl,?


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Anal,tic Frame/or+ Prevention;

Targets

Population(s)

Health

OutcomesInterventions

Toxicities/

Harms

Intermediate

Endpoints

1

2

3


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Anal,tic Frame/or+ Screenin!;

Direct Path/a,;

Persons

at Ris+

arl,

CancerDetection

Intermediate

utcomes

• Sur!er, for cure

• Decrease' late

sta!e 'isease

A'verse >ffects

of Screenin!A'verse

>ffects

of Treatment

8ealth utcomes4 Cancer *ortalit,4 verall *ortalit,4 7ualit, of )ife

Societal utcomes1Tra'e ffs4 8ealthcare

@tiliation4 Cost >ffectiveness


12/27 %#

B Times" June " %6#5

EDr0 3loo'!oo' of Johns8op+ins 'eclares elimination

of canceralmost sure in

earl, sta!e0E


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)ea' Time 3ias

S,mptoms

Death

)ea'Time3ias

Screen 'etection


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%5


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%9

Are Increasin! 92ear Survival Rates

>vi'ence of Success A!ainst Cancer?

A b s

o l u t e I n c r e a s e i n 5 ! e a r

"

u r v i v a l # $ 5 % #

$ $ 5 &

'

5%

%

%

*%

#%

%#%% % #%% *%% %% %%

' +hange in ,ortalit- (#$5%#$$.)

Pearson r 0%%"pearman r 0%1

5S- Statistics7

HG Welch, JAMA, 2000


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%&

A Closer )oo+ at utcomes

8ealthutcomes

Surro!ate>n'points

Very Important Unclear Importance

HHHH00? ? ? ? ? ? ? ? ?8e+erdeaths,period

8e+erdeathsdue tospecific

disease

8e+ercomplications ofdisease

8e+erdiagnosesof disease

9ettertest

results

hangein ris"factor


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%(

Confoun'in! ariales

Exposure Outcome

+on2ounder

Confounding is the death of anystud !


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%

Confoun'in! is a concern in an,oservational stu',

onfounding is more li"ely +hen someone)schoice 5patient, doctor, etc.7 determined +ho

+as in the eposed and uneposed group


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%6

Confoun'in! ariales

3olvo4eer

accidents

6

8i!h S>S

Safet, conscious


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#$

Confoun'in! ariales

8ormone


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Confoun'in! ariales

itamin1

Supplement

Inta+e

)o/er rate of

Cancer" 8eart

DiseaseH

6

8ealth

consciousness

8ealth insurance

Access to care


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##

servational Stu'ies

:/are guilty until proven innocent.;


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#4

I'eas" pinions

Case Reports

Case Series

Case Control Stu'ies

Cohort Stu'ies

Ran'omie'

Controlle' Stu'ies

Ran'omie'

Controlle' Doule3lin' Stu'ies


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#5


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#9


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#&


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///0cancer0!ov ///0cancer0!ov1espanol

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The Science of Cancer Prevention