CPch.4 - Research Methods in Psychopathology Flashcards
Research Designs
What are the different Research Designs?
- Case Study
- Correlational Method
~ Epidemiology - Behavior Genetics and Methods
- Experiment
(Case Study)
What is a Case Study?
When we record detailed info about one person at a time (not many individual people at the same time)
What are the negatives of a case study?
- Objectivity of case studies is limited ->Author’s view shapes the kind of info reported in a case
- Not good evidence in support or against a pre-existing theory, because a case study can’t rule out alternative hypotheses
What are the positives of a case study?
- Good at disproving ONLY an allegedly universal hypotheses (ALL people with depression have ONLY these symptoms, case study with another symptoms immediately disproves this)
- Good at generating new hypotheses, which can be tested through research (examples with Patient H.M.)
- Good at providing rich descriptions of new/unusual clinical phenomena, and at providing the basis for new treatments
(Correlational Method)
What is the Correlational Method?
Observe the correlation between two variables
When and Why do we use this method?
- Used because of ethical reasons -> can’t manipulate many risk variables (trauma, genes for example)
- Used to study incidence and prevalence of risk factors in disorders
- Used in behavioral Genetics to study heritability of disorders (H)
- Used when we want to study important influences that can’t be manipulated
What does statistically significant mean?
When we’re able to determine that a result/observation from a set of data is due to intrinsic qualities and not due to random variance
What does clinically significant mean?
When we’re able to determine whether an effect is large enough to be able to predict a disorder (researching the correlation between risk factors-disorders) or to be able to treat a disorder (researching the correlation between risk factors-treatment)
What is the problem of Causality (also called directionality problem)?
Does Variable X cause the observed results in Variable Y, or Does Variable Y cause the observed results in Variable X
Out of longitudinal and cross-sectional studies, which one of the two is a good solution for solving this problem and why?
Longitudinal studies: Because of the long-time of these studies, you’re able to test if causes are present before a disorder develops (observe risk factors over time, and then in the end observe who develops a disorder)
- High-Risk method (e.g. schizphrenia): Sample only people with above-average risk for schizophrenia. This method is good for studying the onset of disorders
What is a problem with Longitudinal studies?
3rd Variable problem (confounds): Difficult to account for all possible confounds
Why are cross-sectional studies not a solution to the problem of causality?
Because we measure causes and effects at the same time, and thus can’t determine which causes what
What is Epidemiology?
The study of how a disorder is distributed in a population
- Focuses on 3 features of a disorder:
~ prevalence: proportion of people with disorder currently or during their lifetime.
~ incidence: proportion of people who develop this disorder within a specific time period (usually a year)
~ correlates: what other factors/variables correlate with this disorder)
What is a problem with Epidemiology?
Although it’s designed to be representative, many times epidemiologic studies are not (e.g. samples from undergraduate students -> more likely for anxiety or mood disorders, treatment centers -> more likely for ANY DISORDER (duuuhh)
What are some general findings from epidemiologic studies?
46.4 to 60% of people will meet criteria for a disorder at some point in their life
What is the helpfulness of Epidemiology?
- Knowing that disorders affect so many people: reduces stigma
- Knowledge about correlates: clues to potential causes for a disorder
(Behavior Genetics - Methods)
What are the 3 Behavior Genetics Methods to study psychopathology?
- Family method
- Twin method
- Adoptee method
What is the Family method?
When you study the genetic predisposition among family members because the number of genes shared between them is known
What are 1st degree and 2nd degree relatives?
- 1st degree relatives: share 50% of genes
- 2nd degree relatives: share 25% of genes
What is the process of the family method?
1/. Sample a person with a diagnosis in question (person is called index case/proband)
2/. Study relatives -> determine how likely it is for them to have the same diagnosis
e.g. 10% of relatives of index case with schizophrenia are likely to have schizophrenia as well, compared to 1& of the population
What is a problem with the family method?
The data yielded aren’t easy to interpret, because they don’t take into account the environment (nature vs nurture)
What is the Twin method?
Study Monozygotic (MZ) and Dizygotic (DZ) twins
- When MZ consistency rate for disorder > DZ consistency rate for disorder, the characteristic being studied is heritable
What is the adoptee method?
When you study children who were adopted/reared apart from their biological parents
++ Clear-cut findings, because this method studies the gene-environment interaction to determine the correlation with disorder
~ Adoptee with biological parents with APD and unhealthy adoptive family are more likely for APD compared to:
1. Adoptee with biological parents with APD and healthy adoptive family, or:
2. Adoptee with biological parents without APD and unhealthy adoptive family
(Cross-fostering as well, child is adopted and studied in accordance with biological family)
(Experiment)
What is an experiment?
1/. Random assignment of people to conditions (usually 2)
2/. Manipulation of IV
3/. Measurement of DV (observed results in DV varies with conditions of IV)
- Difference in conditions of DV: experimental effect
What are single-case experiments?
Experiments with only one participant
What are the positives and negatives of single-case experiments?
+ high internal validity
- Low external validity
What is a variation of a single-case experiment?
Reversal ABAB Design
What is the Reversal ABAB Design?
Initial Time period (Baseline) (A1)
Period with treatment (B1)
Back to Baseline (not treatment) (A2)
Back to treatment (B2)
If behavior in B1 is different from A1, then goes back to A1 in A2, and then again back to B1 in B2, and the changes in behavior are the same, change is due to manipulation of IV
What is a problem with the reversal ABAB Design?
Sometimes it’s impossible to reverse a manipulation or an action
Treatment Outcome Research
What is the purpose of a treatment Outcome Research?
To define if a treatment works
- 75% of population that enters treatment -> has some positive outcome (but the rest 25%?)
What are the standards for a treatment outcome research to be valid?
- Definition of sample and it’s diagnoses/problems being addressed
- Description of treatment (treatment manual), and then finding a treatment with positive effects, in order for the treatment to be picked
- Inclusion of control group/comparison group
- Experimental design
- Reliable and valid outcome measures
- Blind rater of outcomes (unaware of treatment-unbiased)
- Large n size
What are Randomized Control Trials (RCT’s)?
Studies which randomly assign people to receive a specific treatment
Why does the APA report on therapies that have received empirical support?
To make it easy for people to find literature about these treatments (Empirically Supported Treatments [EST’s])
- If a treatment isn’t on the list, it’s because of the lack of careful studies
What used to be the goals of treatment, and what are today’s goals?
- In the past: treatments were designed to address a certain diagnosis
- Today: Target a mechanism involved in psychopathology (e.g. low motivation)
What is the purpose of having treatment manuals?
- Provide details on how to conduct a particular psychological treatment (also info about procedures one ach stage, for the therapist to know)
- Give idea for what happens in a therapy session
- Used and recommended for psychotherapy research
What are the different type of control groups used in treatment outcome research?
- No-treatment group: used to see if passage of time has the same effect as treatment
- Placebo group
~ Placebo effect: can be a problem, but can also induce long-lasting and large positive effects
(!!! These two control groups are unethical, because they administer no help to patients, so they suffer !!!) - Active-treatment control group: administer to patients a different treatment from the one in the experimental group.
~ Difficult to show a difference between different types of treatment
(When outcomes in a treatment trial are evaluated, always use double-blind procedure: psychiatrist and patient don’t know whether treatment is real or a placebo)
When it comes to choosing the right sample, what must researchers take into account?
- They must recruit people that mirrir the characteristics of real-world people who would seek help for psychological syndromes (sample people who actually need and want help)
- They must take culture into account: plays a big role in who seeks and receives treatment
(e.g. Non-Western, minorities are less likely to seek/receive treatment than white, non-Hispanic adults in the U.S.)
What is efficacy and effectiveness of a treatment?
- Efficacy: If a treatment works in a ideal scenario
- Effectiveness: If a treatment works in the real world
How can we implement a treatment in the real world?
Through Dissemination: Adopting an efficacious treatment in the real world (combination of effectiveness and efficacy of treatment)
What are 5 factors in improving the efficacy and effectiveness of healthcare?
- Dimensions of quality: Safety, effectiveness, patient-centerdness
- 4 Functions of healthcare: Prevention, acute and chronic palliative care (care for a life-threatening disease)
- 3 activities of quality strategies: set standards, monitor, assure improvements
- Donabedian’s Triad: structures, processes and outcomes
- 5 main targets of quality strategies: health professionals, technologies, provider organizations, patients, payers
Analogues in Psychopathology Research
What are Analogue experiments?
When we create a related but less severe phenomenon, an analogue of the risk variable, in the lab, in order to conduct a study
- good internal validity
- bad external validity (don’t study actual phenomenon of interest)
When do we use an analogue in experiments?
When the experimental method can’t be used to understand causes of psychological disorders
(e.g. certain types of mothers cause generalized anxiety disorder -> assign (randomly) infants to 2 groups of mothers
group 1: straining for overdependent atmosphere
group 2: no training
then wait for infant to grow up === IMPOSSIBLE)
What are the 3 types of analogue experiments?
- Type 1: Temporary symptoms are produced through manipulations (e.g. lactate infusions cause a panic attack)
- Type 2: Use of analogue samples (participants are similar to people with certain diagnoses)
- Type 3: Use animals to understand human behavior
!!! When interpreting studies -> Validity of analogue is key !!!
What are general opinions and evaluations of analogue experiments?
Although many criticize them, many also believe that they can be very useful if considered conjointly with studies that don’t rely on analogues (provide us with precision of experiment, if considered with proper experiment)
Integrating Multiple Studies
What are the two ways in which we can integrate multiple studies?
- Replication
- Meta-Analysis
(Replication)
What does it mean when a study has replicability?
Findings from this study help up in a repeated 2nd study)
What are some problems with replicability?
- If there’s a lack of replicability: reduction in trust and investment in Science
- Publication Bias: Joursla prioritize positive over negative findings (negative = uninteresting)
(positive: effect/correlation, negative: no-effect/no-correlation)
What are some reason why there might be failure to replicate a study?
- Statistical analyses rely only on probability, and don’t think about confoufnd
- Small Samples
- Unreliable measures
- Methods of original research study aren’t described well
- Some phenomena may not generalise
- Questionable research practices
- Confirmation bias
- P-hacking: publish good results to obtain promotions, future grant funding etc.
What are some solutions to the above problems?
- Pre-register hypothesis
- Make data publicly available
- (to improve odds that negative findings will be published) weigh rationale and methods of a study more heavily than statistical results
- Large sample sizes
- Consider whether findings have been replicated
(Meta-Analysis)
What is a Meta-Analysis?
The examination of data from a number of independent studies of the same subject, in order to determine an overall trend
Why do we use a Meta-Analysis?
Because it solves the problem of when somebody’s bias affects what conclusion the person draw from many studies
What are the steps in a Meta-Analysis?
1/. Identify all relevant studies
2/. (Because different studies use different statistical methods) -> puts all results into a common scale, called effect size
3/. Consider publication bias
!!! A good meta-analysis is clear about the criteria for including/excluding studies
What is some criticism of Meta-Analysis?
- Inclusion of poor quality studies?
- Poor quality studies are weighed in the same way as good quality ones
- In the end, some personal bias will exist (everybody has their own criteria for separating good and bad studies, or for choosing which studies to include and which to not)
