Which of the following is an example of a double-blind study?
A. participants are randomly assigned to a treatment group or a control group
B. participants and researchers both know which group participants are assigned to
C. participants do not know which group they are assigned to, but researchers do
D. Both participants and researchers do not know which group participants are assigned to
A double-blind study is a research design in which neither the participants nor the researchers know which group participants are assigned to. This is done to minimize bias and ensure that the results of the study are as objective as possible. In a double-blind study, the treatment and control groups are randomly assigned, and the participants and researchers are unaware of which group each participant is assigned to.
Option a) is an example of a randomized controlled trial, which is a common research design, but it is not necessarily double-blind.
Option b) is an example of an open-label study, in which both the participants and the researchers know which group each participant is assigned to.
Option c) is an example of a single-blind study, in which the participants do not know which group they are assigned to, but the researchers do.
Therefore, the Correct Answer is D.
More Questions on TEAS 7 Science
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Q #1: Which part of the respiratory system is responsible for regulate breathing rate and depth?
A. Bronchi
B. Alveoli
C. Diaphragm
D. Trachea
Answer Explanation
The diaphragm is responsible for regulang breathing rate and depth. It is a dome-shaped muscle located at the botom of the chest cavity that contracts and relaxes to help move air in and out of the lungs.
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Q #2: What is the primary physiological function of erythrocytes in the human circulatory system?
A. Facilitation of gas exchange in the alveoli
B. Regulation of blood pH through the release of bicarbonate ions
C. Transportation of oxygen to body tissues
D. Synthesis of clotting factors in response to vascular injury
Answer Explanation
Red blood cells, also known as erythrocytes, play a crucial role in the circulatory system, primarily by facilitating the transportation of oxygen to body tissues. The other choices are also explained below:
A. Facilitation of gas exchange in the alveoli: While gas exchange occurs in the alveoli of the lungs, it is primarily carried out by the respiratory system and involves the exchange of oxygen and carbon dioxide between air and blood. Red blood cells do not directly participate in this process.
B. Regulation of blood pH through the release of bicarbonate ions: The regulation of blood pH is mainly maintained by the bicarbonate buffering system, which involves the action of the respiratory and renal systems. Red blood cells do play a minor role in transporting carbon dioxide, which can indirectly influence pH, but it's not their primary function.
D. Synthesis of clotting factors in response to vascular injury: Clotting factors are primarily produced by the liver and are involved in the blood clotting process to prevent excessive bleeding. Red blood cells are not directly responsible for synthesizing these factors.
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Q #3: Which of the following statements is true regarding vaccines?
A. Vaccines can cause the disease they are designed to protect against
B. Vaccines work by providing passive immunity to the individual
C. Vaccines work by exposing the individual to a weakened or inactivated form of the pathogen
D. Vaccines only provide protection against bacterial infections
Answer Explanation
Vaccines are a type of preventative medicine that work by exposing the individual to a weakened or inactivated form of a pathogen (such as a virus or bacteria) or to a piece of the pathogen (such as a protein or sugar) that triggers an immune response in the body. This exposure allows the body to develop immunity to the pathogen without getting sick from the full-blown disease. Once the immune system has been primed, it can recognize and quickly respond to the pathogen if it is encountered again in the future, providing protection against the disease.
It is a common misconception that vaccines can cause the disease they are designed to protect against. This is not true. While some vaccines may cause mild symptoms such as a low-grade fever or soreness at the injection site, they do not cause the full-blown disease.
Vaccines provide active immunity, meaning that the body produces its own antibodies against the pathogen, rather than receiving pre-made antibodies as in passive immunity. Additionally, vaccines can be effective against both bacterial and viral infections, depending on the specific vaccine.
