Assessment Materials: Deb Rumsey (with Lynda Ballou) 1. "Study Suggests Light to Back of Knee Alters Biological Clock" (NY Times, 1/16/98)

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1 Assessment Materials: Deb Rumsey (with Lynda Ballou) Out of Class Exercises 1. "Study Suggests Light to Back of Knee Alters Biological Clock" (NY Times, 1/16/98) Subjects were divided into two groups. The first group were treated with light shining on the backs of their knees at various times during the day, the others were not (although they were treated with a placebo-an instrument that emanated no light.). After a certain period of time, their biological clocks were measured. Those treated with the light had their biological clocks advanced or delayed up to three hours, compared to the other group. This was indicated by the timing of change in melatonin and body temperature. In this experiment, fifteen volunteers went to a laboratory for four days and nights. On the first night, researchers determined each person's biological rhythm using two measurements: body core temperature and rise in melatonin. Body temperature rises throughout the day and declines at night until morning, when it rises again. Melatonin begins to increase late at night, and falls off during the day. One reason this is important is that it may provide a treatment for jet lag, insomnia, or seasonal depression. Many experts are waiting to see if the experiment can be repeated before they draw any conclusions. It is not known at this time as to why the light has such an effect. The experts believe that "somehow a message is getting from the back of the knee to the master clock in the brain." The results are published in the journal Science (Jan-Feb, 1998). The experiment was conducted by Dr. Scott Campbell and Dr. Patricia Murphy of the Laboratory of Human Chronobiology at Cornell university Medical College in White Plains, NY. a. Why would researchers want to develop a treatment to alter someone's biological clock? b. What treatment is being tested in this experiment? c. Dr. Michael Menaker, a biologist at the University of Virginia in Charlottesville was quoted as saying (paragraph 4): "We were all flabbergasted. For three days we tried to find flaws in the experiment and we couldn't." Do you see any flaws in this experiment? i. Selection of Participants:

2 i iv. Controls for other variables: Was the study blind? Double blind? They measured the timing of a person's biological clock using body temperature changes. Do you think this is a valid measurement? d. The researchers were also quoted in the original article as saying: "Those getting the sham treatment experienced small but statistically insignificant changes in their bodily rhythms (compared to the treatment group)." What does this mean? e. Keep in mind that newspaper articles don't always give us enough information to tell whether or not an experiment is well done; however they usually give us the source of their information. Where would we go to find the original article that describes this experiment in detail? f. Based on these results of this experiment, can we conclude what is said in the first sentence of the original article: "In an experiment from the strange but possibly true category, scientists have shone a bright light on the backs of human knees and, in some mysterious way, resent the master biological clock in the human brain." g. The researchers still don't know why shining a light on someone's knee might cause a person's biological clock to be reset. What might be the researcher's next step? h. Dr. Thomas Wehr, National Institute of Mental Health, is quoted as saying "...until others repeat the experiment, the findings have to be regarded as preliminary." i. Why is it important to make a qualifying statement like this? Explain what this means, in terms of how the public should view press releases about "scientific breakthroughs." 2. "11-Year-Old's Experiment Challenges Therapeutic Touch" (NY Times, 1/16/98.) Emily Rosa, Loveland Colorado, is eleven years old. When she was nine, she designed and conducted an experiment that challenges the effectiveness of a leading treatment in alternative medicine, therapeutic touch. Therapeutic touch is a treatment where someone designated as a "healer" passes their hands over a patient's body without touching the patient. For those that practice this type of treatment, it is thought that the healer's hands manipulate the human energy

3 field. Thousands of people have been trained in healing centers and medical centers all over the world to conduct this treatment. But Emily wanted to know the following: Can therapeutic touch practitioners actually detect a human energy field? Her experiment was conducted in the following way, using twenty-one practitioners who volunteered to participate. She set things up so that a screen separated Emily from the practitioner. Emily flipped a coin to decide which of the practitioner's hands to concentrate on, right or left. Once that was decided, she hovered her hand over the chosen hand of the practitioner. She asked the practitioner which hand it was. Results: In 280 tests, the healers identified the correct hand 44 percent of the time. This was concluded as being "no better than chance." Emily's results have received mixed reviews. Some say it's overwhelmingly clear and effective, and shows what they already believed, that therapeutic touch is not a scientific treatment and does not help patients. Others say her study was poorly conceived, and that no one really knows how to prove the effectiveness of therapeutic touch. One healer, Marilee Tolin pointed out that healers rely on more than just touch to sense the human energy field, including intuition and sight. a. What was Emily's research question? (What claim is she challenging?) b. Evaluate Emily's experiment: i. Did she randomize? i Did she repeat the experiment? Did she control for other variables? c. Emily is trying to measure whether or not a healing practitioner can actually detect a human energy field. She measures this by asking the healer to decide over which of their hands Emily's hand was hoveringtheir right hand or their left hand. Is this a valid measurement of detecting a human energy field? If yes, why? If no, what else would you use? d. Her results say that the healers "did no better than chance." " They identified the correct location of Emily's hand just 44 percent of the time. If they guessed at random, they would have been right about half the time." i. Why would we expect them to get 50% correct just by chance?

4 Since there were 280 experiments performed on 21 practitioners, we assume Emily repeated the experiment several times on each practitioner. However, she then combined all her results into one percentage. Her conclusion was that the healers did no better than chance. Can we be sure that this is true for all of the healers in the group? (How should she report her evidence so we could find out?) e. What is the impact of Emily's experiment on the community of healing practitioners? What was their response to this? 3. "Studying Aging in Space? Send an Aging Astronaut." (NY Times, 1/27/98.) This article pertains to John Glenn's second flight into space at the age of 77, in October, During that space shuttle mission, John Glenn underwent a battery of medical tests and scientific experiments to help NASA scientists study the effects of aging in space. Glenn acknowledged the limitations of these studies: "One person does not a database make," he said. "But you have to start somewhere." Two of the experiments he participated in involved assessing muscle loss and sleep disturbances in space. He also participated in experiments involving various medications and other substances. He did not know whether he was taking a placebo or an actual drug at any time. NASA has an entire database on John Glenn, over 42 years worth of data. NASA acknowledges that the data could be valuable for giving clues to lead them on later investigations, but that the data are not comparable since many of the experiments Glenn participated in during the second mission were never done before. John Glenn is the oldest person to go into space. The second oldest person was 16 years younger than John Glenn. a. Why was John Glenn sent into space in 1998? b. NASA has over 42 years of data on John Glenn. However, what can we conclude when doing an experiment on one person? i. Discuss some of the limitations from a statistical point of view. What are some of the limitations on doing experiments on large numbers of people in space?

5 i iv. What other types of experiments can you think of that are limited in terms of the number of subjects? What kind of information can be gleaned from studies such as this? v. How should we interpret results of experiments that are based on one individual (or only on a small number of individuals)? 4. "Patient or Guinea Pig? Dilemma of Clinical Trials" (Note this article is about a woman from Westmoreland, KS.) This article is about a woman from Westmoreland, KS, who has chronic hepatitus C, a liver disease. Treatment for this disease is very expensive, and her insurance would only pay for half of the costs. Her doctor recommended that she volunteer to participate in a medical study (clinical trial) that would provide medication at no cost to her. She entered a 48-week clinical trial at U Nebraska in Omaha, sponsored by Schering-Plough Corp of Madison, NJ. In this clinical trial, there were 600 participants from medical centers around the U.S. Some of the patients received Rebetron, a medication that has already been approved by the FDA for current use for this disease (made exclusively by Schering-Plough Corp.) Rebetron contains two components: ribavirin and interferon. The other patients in the study received ribavirin, but with higher doses of interferon. One of the purposes of the study was to find out if the higher dosage of interferon would help more patients than the regular dosage. The study was not blind for either the patients or the doctors. Patients were assigned randomly to a treatment group. Researchers told all patients to expect some possibly serious side effects during the 48 week trial, including fever, headaches, nausea, depression, etc. Ms Odgen was grateful to receive the treatment, however, and agreed to participate, but she also decided for herself that if she didn't see improvements within the first few months, that she would drop out of the experiment. To measure her improvement, she planned to look at the viral load statistic, which measures the level of the virus in the bloodstream. However, Schering-Plough did withheld the viral load information from all participants throughout the study, in hopes of keeping people from dropping out. Their point was that dropouts leave them with incomplete data, and would harm their research results.

6 After just four weeks, Ms Odgen developed severe anemia-so severe that her doctor halted the drug temporarily, then allowed her to take it again at a lower dose. She experienced other side effects that were very serious, forcing her to take disability leave from her job. She still participated, although she was very angry with the company. A review board conceded that the researchers did state clearly on the consent forms that patients were not allowed to get the viral load statistics, and they said they were convinced by the drug company that in order to minimize dropouts, they needed to withhold the information. The chairman of the review board at the U of Nebraska said: "It's a tough ethical problem. Her point of view is valid. The investigator's is too." a. Why do people agree to join experimental drug studies? b. Do you think it was wrong for the drug company to withhold the information about Ms. Odgen's progress during the experiment? c. If the company did give her the information, and she decided to drop out, how may this have affected the results of the experiment? d. Suppose there are many people in this study who are in the same situation as Ms Odgen? If most of them dropped out, how might that affect the future of this possibly life-saving drug? e. There are review boards that oversee clinical trials such as this one. What was their stand on this issue, and did they make the right decision? f. Under what conditions would you participate in a clinical trial? g. Most, if not all, clinical and medical experiments use volunteers as participants, rather than a truly "random sample." i. How might this affect the results? What alternative is there to using volunteers? Is it ethical and practical to do anything else?