Biology Now, 2e

30 ■ CHAPTER 02 Evaluating Scientific Claims

SCIENCE

a meta-analysis (work combining results

from different studies) of five cohort studies—

observational studies of a group of people over

a certain period of time—involving 1,256,407

children. The researchers also looked at five case-

control studies—studies comparing patients

with a disease to those without—involving

9,920 children. The data showed no relation-

ship between vaccination and autism, autism

and MMR, or autism and thimerosal (a mercury-

containing preservative in some vaccines).

The work, published in the journal Va cc ine,

included data from the United States, United

Kingdom, Japan, and Denmark on vaccines

for measles, mumps, diphtheria, tetanus, and

pertussis.

Many more peer-reviewed studies with good

control groups and sufficient sample sizes,

children. Instead, the subjects were picked

specifically for their symptoms. Third, the

study did not have a control group, such as

children who had been vaccinated but did

not show signs of autism, or children who had

autism but had not been vaccinated. Finally,

and most important, the finding could not be

repeated. In fact, as of October 2016, at least

110 published papers, studying millions of chil-

dren, have found no evidence of a link between

vaccines and autism. Vaccination does not

cause autism, and the two are not even directly

correlated. In fact, studies first published in

March 2014 provide evidence that autism

begins in the womb, before birth.

In one of the most recent papers, research-

ers at the University of Sydney in Australia,

who stated no conflicts of interest, performed

Evaluating

Scientific

Claims

CREDENTIALS:

Does the person

making a scientific

claim have a PhD

or MD? Is the

degree in the field

in which the claim

is being made?

PEER REVIEW &

PUBLICATION:

Has the claim been

reviewed by

practicing scientists

and published in a

reputable scientific

journal?

BIAS or AGENDA:

Does the person

making the scientific

claim hold a belief

that will be supported

by the claim? Does

he/she stand to make

money if others

accept the claim?

REAL SCIENCE or

PSEUDOSCIENCE?

Does the scientific

study purporting

to support the

claim meet the

standards of

the scientific

method?

Figure 2.8

Evaluating scientific claims

We are constantly bombarded with scientific claims. A few simple questions will help you evaluate which

of these claims are valid and which are not.

Q1: Why is it important to know the education and expertise of a person making a scientific

claim?

Q2: List at least five possible biases that people making scientific claims might have.

Q3: Describe a situation in which you might not dismiss the scientific claim of a person who did

not have appropriate credentials, or who had a bias toward the claim.