Conducting Health Research

Conducting Health Research CHAPT ER 2 Conducting Health Research Lecture Outline I. The Placebo in Treatment and Research A placebo is an inactive substance or condition that can cause people to improve or change their behavior. Both expectancy and learning contribute to this effect. A. Treatment and the Placebo The placebo effect is an advantage for treatment, boosting its effectiveness. This effect may be responsible for about 35% of improvements, but some treatments (such as antidepressant drugs) have higher placebo effects than others (such as treatment for broken bones). Placebos can also produce negative effects, called the nocebo effect. Both placebo and nocebo effects are real and produce symptoms and relief that are indistinguishable from the effects obtained from drug and other physical treatments. B. Research and the Placebo The placebo effect presents problems for research because they prevent a clear interpretation of treatment effectiveness. Researchers try to control for placebo effects by designing single-blind and double-blind designs, arranging for participants and even researchers to be unaware of which participants receive a placebo and which get active treatment. II. Research Methods in Psychology For research to contribute to knowledge about health, scientists should be familiar with one another's work, use controlled methods, try to keep personal biases from contaminating results, make claims cautiously, and replicate their studies. To understand behaviors related to health and disease, researchers use a variety of methods, including correlational studies, cross-sectional and longitudinal studies, experimental designs, and ex post facto designs. A. Correlational Studies Correlational studies indicate the degree of relationship between two variables, such as the number of stressful life events and the risk of heart attack. This approach is one type of descriptive research. In correlational studies, the relationship between two variables is expressed in terms of correlation coefficients. Coefficients range from -1.00 to +1.00, with numbers closer to ±1.00 indicating stronger relationships. Attributions of cause and effect are not possible from correlational studies B. Cross-Sectional and Longitudinal Studies Cross-sectional studies are conducted at one point in time and compare people of different ages, whereas longitudinal studies follow participants over an extended period of time. Cross-sectional studies can show differences between groups, but longitudinal studies can reveal developmental trends. This characteristic is an advantage of longitudinal studies, but they have the disadvantage of taking a long time and being expensive. C. Experimental Designs Experimental designs can determine cause and effect relationships by manipulating an independent variable and observing the effect on a dependent variable, for example, comparing an experimental group on a low-fat diet (treatment group) to participants who maintain their regular diet (control group) and then measuring the development of Multiple Choice Questions 24 lOMoAR cPSD| Conducting Health Research 1. An inactive substance or condition that has the appearance of the independent variable and that may cause participants in an experiment to improve or change behavior due to their belief is called a. a nocebo. b. a placebo. c. a dependent variable. d. an experimental design. ANS: b REF: The Placebo in Treatment and Research 2. The effect of a placebo varies according to people's expectancies and previous learning, but in general, that response rate is about a. 5%. b. 10%. c. 35%. d. 60%. ANS: c REF: The Placebo in Treatment and Research 3. Which of these conditions is likely to produce the highest positive placebo effect? a. a physician dressed casually in blue jeans and sneakers b. a physician who is enthusiastic in describing the treatment c. a physician with a reputation for medical errors d. a physician who, when prescribing medication says, "This may not help, but it won't hurt." ANS: b REF: The Placebo in Treatment and Research 4. The placebo effect is a. most prominent in well-designed experiments. b. an imaginary effect applicable to everyone. c. an imaginary effect that occurs almost exclusively in hypochondriacs. d. physiologically real and capable of improving organic and psychological symptoms. ANS: d REF: The Placebo in Treatment and Research 5. Which of these "sugar pills" is likely to have the greatest positive effect? a. white pills rather than colored pills b. very small pills rather than middle size pills c. capsules rather than tablets d. generic pills rather than brand-name drugs ANS: c REF: The Placebo in Treatment and Research