EBPS Flashcards
p-value
determines the strength of evidence against a null hypothesis
null hypothesis (H0)
assumption that there is no significant difference, effect, or relationship between two or more groups or variables being studied
Alternative Hypothesis (Ha)
It usually suggests the presence of a significant effect, difference, or relationship.
hyperlipidemia
elevated levels of lipids in the bloodstream, including cholesterol and triglycerides, which can increase the risk of cardiovascular diseases
Normal blood pressure for adults is
120/80 or lower
Retrospective Study
looks at past data or events to examine the relationships between variables to draw conclusions about potential associations or outcomes.
Prospective Study
gathers data from participants moving forward in time, starting from the present and following them into the future to observe and measure outcomes as they occur, often through the design of cohort studies or clinical trials.
Cohort studies
follow a group of individuals, known as a cohort, and track their experiences and health outcomes over an extended period
confidence interval
a range of values that is calculated from sample data and is used to estimate the range within which a population parameter, such as a mean or proportion, is likely to fall with a certain level of confidence.
Epidemiology
- the study of the distribution and determinants of disease frequency in human populations
- the application of this study to control health problems and improve public health
- understand and to control its causes
Biostatistics
concerns with analysis and summarization of raw data in interpretable messages related to human health
Evidence-based medicine (EBM)
using the current best evidence in decision making in medicine in conjunction (together) with expertise of the decision-makers and
expectations and values of the patients/people
clinical research
- studying groups of people who are ill
- studies humans in clinical facilities such as outpatient clinics or inpatient facilities
- the interventions are often about therapy in sick people
- experimental design
- small to moderate size
epidemiological studies
- study people in communities
- preventive interventions
- observational studies
- large sample size
the “Big 6”
- description
- causation
- attribution
- mediation
- interaction
- prediction
Description
addresses how frequent or common are various risk factors, exposure, conditions, or diseases
Causation
addresses establishing causal relationships among biological, behavioral, environmental and other factors within humans.
Attribution
addresses what fraction or how many cases of disease Y can be eliminated if a causal exposure X is eliminated or reduced?
Mediation
- addresses the mechanisms of causal relationships
- Given that X does cause Y, how does X cause Y? What is the mechanism?
Interaction
- addresses when and for whom does X cause/predict Y?
- closely related to causation
Prediction
addresses as to whether some feature A or a combination of features A, B, and C predict the concurrent presence or future occurrence of Y?
How could we determine causes of diseases?
Conduct population studies using epidemiological methods
Why should pharmacists care about Epidemiology?
- practice evidenced based medicine (EBM)
randomized controlled trials (RCTs)
- scientific experiments in which participants are randomly assigned to receive different interventions or treatments
- assess the efficacy and safety of these interventions while minimizing bias
Case-control studies
observational research designs that compare individuals with a specific outcome or condition (cases) to those without it (controls) in order to identify factors associated with the development of that outcome or condition
Steps in Practicing EBM
- identify a good question
- find relevant literature
- critically evaluate data
- synthesize and apply to patients
- recognize gaps and design solutions
Two types of study designs
- experimental
- observational
Experimental study can be categorized as
two
- randomized control trial (RCT)
- non-randomized control trial
observational studies can be grouped as
two
- analytical
- descriptive
analytical studies can be
two
- case-control
- cohort
descriptive studies can be
cross-sectional
internal validity
How well do the study estimates represent what was intended in the study plan?
external validity
- How relevant are the study estimates to the research question?
- AKA: Generalizability
- Are study results applicable to the patient/population/problem in front of me?
three threats to validity
- chance (random error)
- bias (systematic error)
- confouding
chance (random error)
- errors that occur by chance
- improved by increasing sample size
- measured by CI
- can affect precision
- Lots of random error/chance = poor precision
- There can be random error in both sampling and measurement
bias (systematic error)
- can include selection bias, volunteer bias, measurement bias
- can affect accuracy
- errors caused by choices, compromises and mistakes we make in how we conduct our study and not by random processes
- Lots of systematic error/bias = poor accuracy
- There can be systematic error in both sampling and measurement
confounding
third variable associated with both exposure and outcome
prevalence
currently have a disease
incidence rate
definition
new cases per unit person-time
point prevalence
proportion with disease at a particular point in time
period prevalence
proportion with disease at any point in time during the period (short lived ex: COVID-19, migraine)