Question 1
The primary reason for having a control group and a treatment group in a clinical study is
◦ to eliminate confounding variables.
◦ to combat the placebo effect.
◦ to save money.
◦ to make it easier to collect data.
◦ none of these
Question 2
A tamoxifen study claims that a combination of chemotherapy and the hormone therapy tamoxifen is more effective than tamoxifen alone in preventing breast cancer. In the study, a group of researchers from the U.S. and Canada studied 1477 postmenopausal women with early-stage breast cancer. The women were randomly assigned to one of three study groups. Group A (361 patients) received tamoxifen alone on a daily basis for five years. Group B (566 patients) received chemotherapy and tamoxifen for six months, and then completed five years of tamoxifen treatment. Group C (550 patients) received chemotherapy alone for six months followed by five years of tamoxifen treatment. All 1477 patients knew which treatment they were receiving.
This study can best be described as a
◦ randomized controlled experiment.
◦ survey using quota sampling.
◦ survey using stratified sampling.
◦ census.
◦ survey using simple random sampling.
A study by Seehausen and van Alphen involving the effects of male coloration on female choice in Afr
Using a microscope to study the human body
Side-effects of major chemotherapy agents
A combination wrench has an open end at one end and a box end at the other end.
Effect of antidiuretic hormone deficiency.
The first successful gene therapy trial