ACT Science Practice Test 55

PASSAGE III

A mercury thermometer, at an initial temperature of 20°C, was placed in 40°C water, and the temperature registered by the thermometer was recorded over time. This procedure was repeated using water samples at 50°C and 60°C (see Figure 1). Next, the same thermometer, at an initial temperature of 60°C, was placed in an air sample at 50°C, and the temperature registered by the thermometer was recorded over time. This procedure was repeated using air samples at 30°C and 40°C (see Figure 2).

Figure 1

Figure 2

(Note: Assume that the temperatures of the water and air samples did not change during the measurements.)

PASSAGE IV

Clinical research has become an important element in the development of modern medicine. Perhaps one of the most widely-debated issues in today's clinical research is the use of placebos, treatments believed to be biologically ineffective but used anyway for psychological or experimental purposes; an example of a placebo is a sugar pill, which contains no medication. In the realm of clinical research, placebos are used to establish a control group within the pool of research participants. A certain percentage of research patients are administered the test treatment, and another percentage is administered a placebo treatment. Patients are not informed of which percentage they are a part.

For various reasons, the use of placebos in clinical research is a controversial issue. Two scientists debate whether the use of placebos is a good or bad practice in research.

Scientist 1

Placebos are an important aspect of clinical research for many reasons. Not only do they establish a control group for the test treatment in question, but they also help address the issue of mind over matter, which is an important issue when working towards treatment for a particular illness. The body is a powerful life force, with natural recuperative abilities. A placebo encourages such recuperation.

Placebos also address the psychological aspect of illness. Because patients are unaware of whether they are receiving treatment or a placebo, the possibility of receiving treatment often provides patients with a psychological boost. The use of placebos addresses the question of whether a person's positive attitude may be important in recovery from illness. As a result, the placebo effect-a change in the patient's condition due to the idea of treatment, rather than its biological effectiveness-may be a measurable change in behavior as a result of the belief in treatment.

For both their physical and psychological benefits, placebos should be used in clinical research.

Scientist 2

There are many reasons why placebos shouldn't be used in clinical research. For example, placebos encourage deception in the doctor-patient relationship. Because this relationship is crucial to the confidence of both the doctor and the patient, and therefore the overall success of the patient's involvement in a study, placebos not only deceive patients, but can also have an adverse affect on research results. Placebos also violate patients' autonomy, or their right to choose treatment. While they can choose to be involved in a study, patients are unable to select their own course of treatment because it chosen for them.

Some argue that the placebo is worth its implementation in order to evaluate for the occurrence of the placebo effect. However, such action may skew the results of the study. For example, placebo-related changes could be over-estimated. Different illnesses, by definition, will react differently to the placebo. For example, in the instance of chronic pain or mood disorders, it's possible for patients to show spontaneous improvement. The placebo effect can also result from contact with doctors or a respected professional. Patients are vulnerable to their environment, which significantly affects the psychological results of the placebo.

Due to its capability to skew research results, the placebo shouldn't be used in clinical research.