Ch. 12: Research Design & Statistics: A Foundation for Clinical Science Flashcards
Science
A philosophy of events and nature that values evidence more than opinions.
Research
What scientists do as they practice science. The process of asking and answering questions. Methodological process.
Empiricism
The philosophical position that statements must be supported by experimental or observational evidence.
Determinism
Means that events do not happen randomly or haphazardly; they are caused by other events.
Inductive Method
An experiment-first-and-explain-later approach to research. The researcher starts by conducting a series of experiments, and then they propose a theory based on the results of those experiments.
Deductive Method
An explain-first-and-verify-later approach to research. The investigator explains an event and then attempts to verify the explanation through the result of experiments.
Theory
A systematic body of information concerning a phenomenon, describing an event, explaining why the event occurs, and specifying how the theory can be verified. “X causes Y.”
Hypothesis
A prediction stemming from a theory.
Null Hypothesis
Hypothesis stating that two variables are not related.
Alternative Hypothesis
Hypothesis stating that the two variables are related and that perhaps one is the cause of the other.
Data
The result of systematic observation and, in some cases, experimentation.
Qualitative Data
Verbal descriptions of attributes of events.
Quantitative Data
Numerical descriptions of attributes of events.
Validity
The degree to which an instrument measures what it purports to measure.
Predictive/Criterion Validity
The accuracy with which a test predicts future performance on a task.
Concurrent Validity
The degree to which a new test correlates with an established test of known validity. A form of criterion-related validity.
Construct Validity
The degree to which test scores are consistent with theoretical constructs or concepts. For example, a test of language development in children should meet the theoretical expectation that as children grow older, their language skills improve.
Content Validity
A measure of test validity based on a systematic examination of all test items to determine if they adequately sample the full range of the skill being tested and if they are relevant to measuring what the test purports to measure. Based on expert judgment.
Reliability
Refers to the consistency with which the same event is measured repeatedly. Scores are reliable if they are consistent across repeated testing or measurement.
Correlational Coefficient
A number or index that indicates the relationship between two or more independent measures. Usually expressed through r. Expression of reliability. An r value of 0.00 indicates that there is no relationship between two measures. The highest possible positive value of r is 1.00. The lowest possible negative value of r is -1.00. The closer to 1.00, the greater the reliability.
Test-Retest Reliability
Refers to consistency of measures when the same test is administered to the same people twice. When the two sets of scores are positively correlated, the stability of the scores over time is assumed.
Alternate-Form Reliability/Parallel Form Reliability
Based on the consistency of measures when two parallel forms of the same tests are administered to the same people. If both those forms are administered to a child and the scores are very similar, then the test has this form of reliability.
Split-Half Reliability
A measure of internal consistency of a test. Determined by showing that the responses to items on the first half of a test are correlated with responses given on the second half. Generally overestimates reliability because it does not measure stability of scores over time.
Interjudge/
Interobserver Reliability
Refers to the extent to which two or more observers agree in measuring an event.
Intrajudge/
Intraobserver Reliability
Refers to the extent to which the same observer repeatedly measures the same event consistently.
Experiment
A means of establishing cause-effect relationships. Test if-then relationships. Involves a controlled condition in which an independent variable is manipulated to produce changes in a dependent variable.
Independent Variable
Variable directly manipulated by the experimenter. Treatment is an independent variable.
Dependent Variable
Variable that is affected by the manipulation of the independent variable. All disorders are dependent variables. Must be defined very specifically so that they are measurable.
Confounding/
Extraneous Variables
Variables other than independent variables that cause an effect on the dependent variable.
Control Group
Group containing participants who do not receive treatment.
Pretest-Posttest Control Group Design
Experimental research design where there are two groups: an experimental group and a control group. This design helps evaluate the effects of a single treatment. The participants are randomly selected and assigned to groups. Each participant in each group undergoes a pretest and a posttest. Based on the logic that to assess the effects of an independent variable (treatment), the only difference between groups must be that variable.
Pretests
Participants’ existing behaviors or skills measured before starting an experimental treatment or teaching program.
Posttests
Measures of behaviors established after completing the treatment program.
Relative Effects
Questions: “Which treatment is more effective?”
Single-Subject Designs
Research study design that helps establish cause-effect relations based on individual performances under different conditions of an experiment. Allow extended and intensive study of individual participants and do not involve comparisons based on group performances. Measure dependent variables continuously.
ABA Design
The basic single-subject experimental design. Useful in establishing treatment efficacy. The letters designate the different conditions of an experiment. The first A condition refers to baselines. The next B condition refers to treatment. The third A condition refers to treatment withdrawal.
ABAB Design
An extension of the basic ABA single-subject experimental design. Useful in establishing treatment efficacy. The letters designate the different conditions of an experiment. The first A condition refers to baselines. The next B condition refers to treatment. The third A condition refers to treatment withdrawal. The fourth B condition refers to the reinstatement of treatment.
Multiple-Baseline-Across-Subjects Design
Research study design involving several participants who are taught one or more behaviors sequentially (in a staggered fashion) to show that only the behaviors of treated participants change; those of untreated participants do not change. This outcome, too, demonstrates that the treatment was effective. The researcher:
- Selects a target behavior to be taught to three or more participants
- Base-rates the target behaviors in all participants before treatment is applied
- Treats one participant while repeating the base rates on the untreated participants
- Treats the second participant while repeating the base rates on the untreated participants
- Alternates treatment and base rates until all participants are trained