Question

Do blood-building drugs help brain development in babies born prematurely? Researchers randomly assigned 53 babies, born more than a month premature and weighing less than 3 pounds, to one of three groups. Babies either received injections of erythropoietin (EPO) three times a week, darbepoetin once a week for several weeks, or no treatment. Results? Babies who got the medicines scored much better by age 4 on measures of intelligence, language, and memory than the babies who received no treatment.

How was replication used in this experiment?

A)All of the babies were premature with a birth weight of less than three pounds.

B)Babies were measured on multiple variables – intelligence, language and memory.

C)The babies were randomly assigned to the different treatments.

D)There were 53 infants in the study, presumably about 17 infants in each treatment group.

E)There were three different treatments used in the experiment.

Answer 1

In the experiment on blood-building drugs and brain development in prematurely born babies, replication was evident as all babies had similar birth conditions, were randomly assigned to treatments, and there were multiple treatment conditions.

Step-by-step explanation:

Replication in an experiment refers to the process of ensuring that the experiment can be reproduced under similar conditions to verify the results. In the given experiment about blood-building drugs and their potential effects on brain development in babies born prematurely, replication was employed in the following way:

• All of the babies were premature with a birth weight of less than three pounds (option A).
• The babies were randomly assigned to different treatments (option C).
• There were three different treatments used in the experiment (option E).

Options B and D did not represent replication but rather variability and sample size, respectively. In the study, babies received injections of erythropoietin (EPO) or darbepoetin or no treatment, and were later assessed on intelligence, language, and memory. The random assignment of the participants to the treatments is a key component of replication, as it ensures that each treatment group is comparable in terms of potential confounding variables.