Methods in Experiemental Clinical EXAM Flashcards
What were the results of effectiveness with the internet-based behavioral activation therapy
Compared to online psychoeducational it would be more effective at improving depressive symptom
GAF vs online
Logged on mean of 13 vs mean of 2
Uses:
- lower income populations
- places with fewer mental health professionals
- ppl who getting out of the house is a barrier for treatment
Depression and Social Media
No directionality: but found a significant between social media use and depression
- ppl with highest risk of depression was 27-32
Facebook and social anxiety
increased adolescent GAD symptoms were associated with increased Facebook behavior and repetitive Facebook behaviors.
No social anxiety symptoms were found to be associated with Facebook use and/or repetitive Facebook behaviors
no association between depressive symptoms and Facebook behaviors and repetitive Facebook behaviors
what are observational research studies? What do they involves
when variables are manipulated by nature and the investigator evaluates the impact of these variables
through selecting persons for study who have the
characteristic of interest
• Such studies are referred to as “observational research”
to convey that the investigator is to observes (assesses)
different characteristics and their associations, rather
than to intervene experimentally.
Explain what cross-sectional case-control designs are
- most common type of observational design
subjects are selected and
assessed in relation to current characteristics.
• The goal is to examine factors that are associated with a characteristic of interest at a current point in time
Subjects are identified and assessed on multiple
characteristics beyond those used to delineate their
status as cases or controls.
• Because all of the measures are obtained at the same
point in time, the results are correlational
Explain case-control designs
Investigation of a characteristic of interest by forming
groups who vary on that characteristic and studying
other current or past features of those groups
• The key characteristic is in identifying groups who vary in the outcome (criterion) of interest (have or do not have characteristic)
Explain retrospective case control studies
the goal is to draw inferences about some antecedent
condition that has resulted in or is associated with the
outcome.
there can be significant problems that usually preclude
establishing the recalled event as a risk factor (antecedent)
for the outcome of interest.
not all retrospective reports are subject to the same sorts or degrees of bias (discrete events are more reliable than reports of psychological states, but still not great)
Name the strengths of Case-Control designs (6)
Well suited to studying characteristics that are relatively
infrequent in the population
Efficient in terms of resources and time because of the crosssectional
assessment
No attrition because of assessment at one point in time
Can study magnitude type of relations among variables (e.g.,
direct influence, moderating influence)
Allows the investigator to match subjects on one of the variables
assessed at pretest that may influence the results
Can rule out or make implausible the role of influences that might
be confounded with the characteristic of interest
describe the weaknesses of case-control designs (3)
No time line is shown among the variables of interest, so
one cannot usually establish whether one characteristic
preceded the other or emerged together
Causal relations cannot be directly demonstrated, even
though various analyses (e.g., dose–response relations)
can provide a strong basis for hypotheses about these
relations
Sampling biases are possible depending on how the
cases (e.g., depressed clients) were identified and
whether some special additional characteristic (e.g.,
coming to a clinic) was required
what are birth cohort designs
There usually is a specific time frame (e.g., 6- or 12-
month period) and geographical locale.
• Children are followed for an extended period –
(sometimes) spanning decades.
• The strength of the study derives from comprehensive
assessments repeatedly over extended periods.
a large percentage of sample must be retained or poor external validity and selection biases can occur
”New” researchers usually are needed. The
participants (infants) are likely to outlive the careers of
the investigators who started the project.
explain multigroup cohort designs
A prospective study in which two (or more) groups are
identified (Time 1) and followed over time to examine
outcomes of interest.
• A two-cohort design begins by selecting groups that vary
in exposure to some condition of interest (e.g., soldiers
returning from combat) or not (e.g., soldiers returning
who did not experience combat) and follows them to see
what the outcomes will be.
two group cohort design example (head injury)
Youths who received head injury (e.g., accident) were
identified and assessed over time for a 2-year period.
• The obvious control group would be a sample of youths
without a head injury, matched on various subject (sex,
age, ethnicity) and demographic variables (e.g., social
class) that are known to influence patterns of psychiatric
disorders. However, a noninjury group may not provide
the best comparison.
• Perhaps any injury (whether to the head or toes) that
leads to hospitalization for a child (or anyone) is
traumatic and that trauma and entry into a hospital alone
could increase later impairment.
In this study, the second group (making it a two- or multigroup
cohort design) consisted of youths who were
hospitalized for orthopedic injury (e.g., broken bones
from accidents).
• Thus, both groups experienced injury, but head injury
was the unique feature of the index group expected to
predict later psychiatric disorder. Both groups were
followed for 2 years after the injury and evaluated at that
time.
• As predicted, the results indicated that youths with head
injury had a much higher rate of psychiatric disorder at
the follow-up 2 years later when compared with
orthopedic injury youths.
accelerated. multi-cohort longitudinal design
A prospective, longitudinal study in which multiple groups
(two or more cohorts) are studied in a special way.
• Inclusion of cohorts who vary in age when they enter the study.
accelerated because the
period of interest is studied in a way that requires less
time than if a single group were followed over time
- including several groups, each
of which covers only a portion of the total time frame of
interest. The groups overlap in ways that permit the
investigator to discuss the entire development period.
strengths of cohort designs (5)
Can establish the time line (antecedent becomes before some outcome of interest)*
Measurement of the antecedents are not be biased by the outcome (e.g., being depressed now could not influence past
recall of events)
Multiple assessments at different points in time can be used to assess the predictors to chart the course or progression from the antecedent to the outcome
All of the permutations can be studied in relation to the
antecedent (occurred or did not occur at Time 1) and outcome
(subjects did show or did not show the outcome at Time 2)
Good for generating and testing theory about risk, protective, and causal factors and mediators and moderators
weaknesses of cohort designs (5)
Prospective studies can take considerable time to complete, and answers to critical questions (e.g., effect of asbestos on health, effect of abuse on youths) may have delayed answers
Studies conducted over time can be costly in terms of personnel and resources. Retaining cases in a longitudinal study often challenging
Attrition or loss of subjects over time can bias the sample
Cohort effects may serve as a moderator, i.e., it is possible that the findings are due to the sample assessed at a particular point in time
The outcome of interest may have a relatively low base rate.
Statistical power
