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Chapter 4: Q 45. (page 253)

Chocolate and happy babies A University of Helsinki (Finland) study wanted to determine if chocolate consumption during pregnancy had an effect on infant temperament at age of 6 months. Researchers began by asking 305 healthy pregnant women to report their chocolate consumption. Six months after birth, the researchers asked mothers to rate their infants鈥� temperament, including smiling, laughter, and fear. The babies born to women who had been eating chocolate daily during pregnancy were found to be more active and 鈥減ositively reactive鈥濃�攁 measure that the investigators said encompasses traits like smiling and laughter.

(a) Was this an observational study or an experiment? Justify your answer.

(b) What are the explanatory and response variables?

(c) Does this study show that eating chocolate regularly during pregnancy helps produce infants with a good temperament? Explain.

Short Answer

Expert verified

Part (a) Observational study.

Part (b) Since the intake of mother chocolate helps clarify the temperament of the baby.

Part (c) No.

Step by step solution

01

Part (a) Step 1: Given information

Number of healthy pregnant women, n=305

The study found that babies born to mothers who ate chocolate every day during pregnancy were more active and positive in their reactions.

02

Part (a) Step 2: Concept

Observational research looks at people and assesses factors of interest without trying to affect their responses.

03

Part (a) Step 3: Explanation

Because an observatory analysis retrieves information on the possible impact of individuals on a technique, this was an observational study. When the investigator has no influence over whether subjects are assigned to a treatment group or a control group. The researchers also questioned their chocolate consumption and attitudes toward newborns.

04

Part (b) Step 1: Explanation

Because chocolate consumption by the mother helps to clarify the baby's disposition. The intake of mother chocolate and the nature of the infant are the explanation and response.

05

Part (c) Step 1: Explanation

No. Because this is an observational study, it is impossible to conclude that chocolate consumption during pregnancy consistently results in children with healthy temperaments. The temperament difference could be influenced by a hidden factor.

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