CLINICAL RESEARCH MANAGEMENT 512

Leslie McIntoshlmcintosh at path.wustl.edu

GRAPHS

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2000

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Sample Dataset including male and female subjectsN= 100

Bir

th w

eig

hts

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ms

Gestational age in weeks

Outliers at 10,000 grams, i.e. missing data points

0 5 10 15 20 250

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Birth Weights at Gestational Age

20 wks21 wks22 wks23 wks24 wks25 wks26 wks27 wks28 wks29 wks30 wks

Number of Sample Births

weig

ht

in g

ram

s

PART 2

TYPES OF CLINICAL RESEARCH1. Case Reports

Anecdotal Problem

2. Observational

a. Case Control/Retrospective (lung cancer)

b. Cross Sectional (WESDR) Beaver Dam

c. Prospective (Framington) WESDR-II

Risk Factor Associations

3. Drug Development

(Phase 0, Phase I, & Phase II)

Dose and activity

4. Experimental (Clinical Trial) Phase III

“Effect”

PRIMARY INTERESTS

Exposures – what affected the person intentionally (intervention) or not

Outcomes – what happened to the person Clinical measures Non-clinical measures

ACTIVITY

Exposure Outcome

ERRONEOUS CONCLUSIONS

Correlation is not equal to causation;

it is only a requirement for it.

ERRONEOUS CONCLUSIONS Young children who sleep with the light on are much

more likely to develop myopia in later life. Published from U of Pennsylvania Medical Center in the May 13,

1999 issue of Nature, the study received much coverage at the time in the popular press.

A later study at The Ohio State University did not find a link between infants sleeping with the light on and development of myopia.

It did find a strong link between parental myopia and the development of child myopia, also noting that myopic parents were more likely to leave a light on in their children's bedroom

ERRONEOUS CONCLUSIONS

Correlation does not prove causation