7 Cross Sectional Studies Flashcards
cross-sectional studies are also called ____________________
prevalence surveys
CSS can be thought of as a _______________________ because data are collected and evaluated at a single point in time
snapshot (slice) of time
CSS is more of a hypothesis ___________ rather than hypothesis ________________
generating; testing
CSS is not suited for testing the effectiveness of ____________________
interventions
T/F: CSS are most often used descriptively
T
most often used descriptively to __________________________ about a population (eg. disease prevalence) but may also be used to ______________________ between an independent (exposure) and a dependent (outcome) variable
capture information; examine associations
T/F: CSS establishes causality or relationship between independent (exposure) and dependent (outcome) variable
F (does not establish as CSS is used descriptively, thus only EXAMINES ASSOCIATION)
T/F: CSS is quick and easy to perform
T
CSS is useful for ________________ current health status or _______________ priorities for disease control
measuring; setting
CSS study design
- questionnaire
- surveys
answering a census or through mail or telephone calls are considered what type of study design?
questionnaire
standardized questionnaire used to describe a population at a given point in time
surveys
surveys are generally used to _________________ a population
characterize
steps involved in study design
- identify [target pop]
- select [indiv from pop]
- collect [data]
- analyze [data]
population with desired clinical and demographic characteristics that will ultimately benefit from generalization of the study findings
target population (identifying target pop)
extent to which observations in the study population extrapolates to the overall population of interest
generalizability
selecting a subset of the target population to conduct a study
sampling
types of sampling
- random sampling
- stratified random sampling using characteristics (e.g., age or gender)
- convenience sampling
most common type of sampling
convenience sampling
CSS data collection may either be _______________ or __________________
retrospective or prospective
sample of retrospective data collection
prescription records
sample of prospective data collection
survey
T/F: analysis step of CSS study design is not purely descriptive
F (purely descriptive)
step of study design involved in summarizing the characteristics of the population using means and percentages
analysis
how are characteristics summarized during analysis
using means and percentages
have potential biases that should be considered and interpreted cautiously
analytical cross-sectional studies
CSS limitations
- bias on sampling and temporality
- may not give generalizations
CSS concerns/problems
- errors in data collection
- transient effects
responses that are affected by event, feeling or other circumstance that happened prior to data collection
transient effect
reports without control grps
- case studies
- case reports
- case series
reports w/o ctrl grps can be ________________ or _________________ reports
observational or interventional
key characteristic of case studies, case reports, and case series
lack of control or comparison group
record of descriptive research that documents a practitioner’s experiences, thoughts, or observations related to the care of a single patient
case study
case study focuses on the _____________
practitioner
descriptive record of a single individual (case report) in which the possibility of an association between an observed effect and a specific intervention or exposure (often an unexpected complication of treatment or procedure) based on detailed clinical evaluation and history of the individual
case report
group of records (case studies) that documents a practitioner’s experiences, thoughts, or observations related to the care of multiple patients with similar medical situations
case series
types of case reports
- disease identification
- ADR-reporting
- new treatment approach
- educational
- quality assurance
previously unknown or variant of known condition
disease identification
reader must avoid generalization of rare condition
disease identification
most common source of information for drug removal
ADR reporting
excellent in identifying rare and serious ADRs
ADR reporting
utility in identifying ADRs in special populations
ADR reporting
used to generate hypothesis for further testing with a more resource-intensive design
new treatment approach
may lead to unsubstantiated use of medications for unapproved indications
new treatment approach
present a scenario to help clinicians improve practice skills
educational
practice errors can illustrate problems to avoid by other practitioners
quality assurance
strengths of case reports
- identifies: rare occurrences and delayed ADRs
- hypothesis generation
- requires minimal resources
weaknesses of case reports
- no causal inference, statistical analysis
- potential for reporting bias and false results
strengths of case series
- results are closer to those of routine clinical practice
- may be useful when a randomized controlled trial is challenging to conduct
- high external validity
- cost-effective and time saving design
weaknesses of case series
- no causal inference
- susceptible to selection and measurement bias
- absolute risk cannot be calculated
- data collection may be incomplete
reports w/o control grps are useful for early recognition of ___________________ and ______________
drug toxicities and teratogenicity
an important initial step in the formulation of hypotheses
reports w/o control groups
T/F: when possible, results should be confirmed with randomized controlled clinical trials
T
