chapter 4 Flashcards
what are phenotypes?
observable behaviour or characteristics of individuals
define Randomization.
method for placing individuals into research groups that assures each one of an equal chance of being assigned to any group, to eliminate any systematic differences across groups.
what is a research design?
the plan of experimentation used to test a hypothesis
what is a baseline?
the measured rate of behaviour before introduction of an intervention that allows comparison and assessment of the effects of the intervention.
what are analogue models?
an approach to research employing subjects who are similar to clinical clients, allowing replication of a clinical problem under controlled conditions
define Variability.
the degree of change in a phenomenon over time
what is the Independent variable?
the phenomenon that is manipulated by he experimenter in a research study and expected to influence the dependent variable
what is an Experiment?
a research method that can establish causation by manipulating the variables in question and controlling for other alternative explanations of any observed effects.
what is statistical significance?
the probability that obtaining the observed research findings merely by chance is small
define testability.
the ability of a hypothesis, for example, to be subjected to scientific scrutiny and to be accepted or rejected, a necessary condition for the hypothesis to be useful
what is a trend?
a direction of change of a behaviour or behaviours
explain twin studies.
If twins, particularly monozygotic twins who share identical genotypes, share common characteristics such as a disorder, even if they were reared in different environments, this is strong evidence of genetic involvement in those characteristics.
what is the confound/confounding variable
any factor in a research study that makes the results interpretable because its effects cannot be separated from those of the variables being studied.
what is the patient uniformity myth?
the tendency to consider all members of a category as more similar than they are, ignoring their individual differences
what are single case experimental designs?
research tactics in which an independent variable is manipulated for a single individual, allowing cause-and-effect conclusions, but with limited generalizability
what is a sequential design?
a combination of the cross-sectional and longitudinal research methods involving repeated study of different cohorts over time.
what is the cohort effect?
the observation that people of different age groups also differ in their values and experience
define the placebo effect.
behavioural change resulting from the person’s expectation of change rather than from the experimental manipulation itself
what is the dependent variable?
the phenomenon that is measured and expected to be influenced in a experimental research study
what are association studies?
research strategies for comparing genetic markers in groups of people with and without a particular disorder
what is the level?
the degree of behaviour change with different interventions
define clinical significance.
the degree to which research findings have useful and meaningful applications to real problems
what is a hypothesis?
an educated guess or statement to be tested by research
what are longitudinal designs?
systematic studies of changes in the same individual or group examined over time
what are endophenotypes?
genetic mechanisms that contribute to the underlying problems causing the symptoms and difficulties experienced by people with psychological disorders
what is a longitudinal design?
a systematic study of changes in the same indivudal or group examined over time
what are family studies?
genetic studies that examine patterns of traits and behaviours among relatives
what is the cross-generational effect?
- a limit to the generalizability of longitudinal research because the group under study may differ from others in culture and experience
what is a cross-sectional design?
methodology to examine a characteristic by comparing different individuals of different ages.
- Contrast with longitudinal studies.
what is a negative correlation?
an association between two variables in which one increases as the other decreases
what is a positive correlation?
an association between two variables in which one increases as the other increases
what is a repeated measurement?
when responses are measured on more than two occasions (not just before and after intervention) to assess trends
what is internal validity?
the extent to which the results of a research study can be attributed to the independent variable after cofounding alternative explanations have been ruled out
what is external validity?
the extent to which research study findings generalize, or apply, to people and settings not involved in the study
define confound
any factor occurring in a research study that makes the results uninterpretable because its effects cannot be separated from those of the variables being studied
what is a control group?
a group of individuals in a research study who are similar to the experimental subjects in every way but are not exposed to the treatment received by the experimental group; their presence allows for a comparison of the differential effects f the treatment.
define generalizability
the extent to which results apply to a range of individuals not included in the study
what is effect size?
the statistical measure that shows the amount of difference among the members of a group in a clinical study
what is a case study method?
research procedure in which a single person or small group is studied in detail. The method does not allow conclusions about cause-and-effect relationships, and findings can be generalized only with great caution.
define correlation.
the degree to which two variables are associated.
- In positive correlation, the two variables increase or decrease together
- in a negative correlation, one variable decreases as the other increases
define correlation coefficient.
Computed statistics reflected the strength and direction of any association between two variables
-can range from +1.000 through zero to -1.000, with the absolute value indicating strength, and the sign reflecting the direction
define epidemiology
A psychopathology research method examining the prevalence, distribution, and consequences of disorders in populations.
what is treatment outcome research?
studies of the effectiveness of clinical interventions , including the comparison of competing treatments
what are placebo control groups?
control groups that do not receive the experimental manipulation but are given a similar procedure with an identical expectation of change, allowing the researcher to assess any placebo effect
what is double-blind control?
a procedure in outcome studies that prevents bias by ensuring that neither the subjects nor the providers of the experimental treatment know who is receiving treatment and who is receiving placebo
define comparative treatment research.
the outcome research that contrasts two or more treatment methods to determine which is most effective
what are single-case experimental designs?
a research tactic in which an independent variable is manipulated for a single individual, allowing cause-and-effect conclusions, but with limited generalizability (contrasts with case study method)
what is a withdrawal design?
removing a treatment to note whether it has been effective
- in single case experimental designs, a behaviour is measured (baseline), an independent variable is introduced (intervention), and then the intervention is withdrawn.
- because the behaviour continues to be measured throughout (repeated measurement), any effects of the intervention can be noted
- also called “reversal design”
define multiple baseline
a single-case experimental design in which measures are taken on two or more behaviours, or on a single behaviour in two or more situations
- a particular intervention is introduced for each at different times.
- If behaviour change is coincident with each introduction, this is strong evidence the intervention caused the change
define genotypes.
specific genetic makeup of individuals
what is the human genome project?
the ongoing scientific attempt to develop a comprehensive map of all human genes
define proband.
In genetics research, the individual displaying the trait or characteristic being studied
- Also called “index case”
explain adoption studies
in genetic research, the study of first-degree relatives reared in different families and environments.
- if they shared common characteristics, such as a disorder, this finding suggests that those characteristics have a genetic component
define genetic linkage analysis.
studies that seek to match the inheritance pattern of a disorder to that of a genetic marker; this helps researchers establish the location of the gene responsible for the disorder
what are genetic markers?
inherited characteristics for which the chromosomal location of the responsible gene is known
what are cohorts?
participants in each age group of a cross-sectional research study
what is retrospective information?
literally “the view back”, data collected by examining records or recollections of the past.
- it is limited by the accuracy, validity, and thoroughness of the source
explain informed consent.
the ethical requirement whereby research subjects agree to participate in a research study only after they receive full disclosure about the nature of the study and their own role in it
define incidence.
the number of new cases of a disorder appearing during a specific time period (compare with prevalence)
define prevalence.
number of people displaying a disorder in the total population at any given time (compare with incidence)
