exam 1 Flashcards
what is pharmacoepideminology
the study of the use and effect of drugs in large numbers of people
pharmacology vs clinical pharmacology
pharmacology study of effects of drugs while clinical pharmacology is the study of effect of drugs in humans
epidemology vs pharmacoepi
epidemology is the study of the distribution and determinants of diseases in populations
pharmcoepi is a subset
pure food and drug act 1906
in response to excessive adulteration and misbranding of food and drug at that time. Fed gov now allowed to remove drug that was adulterated or misbranded
food, drug and cosmetics act
in response to people dying from renal failure. Preclinical toxicity testing required and manufacturers required to gather clinical data about drug
Case report
- report of an event in a single patient
- useful in generating hypotheses
Case series and when useful
collections of patients all of whom have either a single exposure or single outcome
- useful: quantify an ADE and ensure ADE are not happening in population larger than that studied prior to drug marketing
case-control studies
compare cases (w/ outcome) to controls (w/o outcome) to look for differences in
cohort studies
a study that identifies a cohort of subjects and follows them over time to determine outcome
random control/clinical trial
a study where participants are randomly assigned between exposure and control groups
pragmatic clinical trials
A study in which the investigator tests the effectiveness of an intervention under ‘real-world’ conditions
different types of bias
- information bias: interviewer and recall bias
- selecting bias: control doesnt represent the population that produced the cases
what is a confounder
a variable related to both the exposure and the outcome
- variable distributed unequally b/w the groups
why dont RCTs translate to the real world
problems with clinical trials
- expensive
- small
- often drugs are compared against placebo
- exclude elderly, children, pregnant women, patients w/ comorbidities
- not timely
- unethical
pragmatic clinical trials design and setting
designed to improve practice and policy
- take place in settings where everyday care happens, such as community clinics, hospitals and health systems
rct vs pct
- GOALS
- RCT determine causes and effects of therapy
- PCT: improves practice and inform clinical and policy decisions
rct vs pct
- design
- RCT: test intervention against placebo
- PCT: test 2 or more real-world treatments using flexible protocols and local customization
rct vs pct
- participants
- RCT: highly defined and carefully selected
- PCT: more representative b/c less strict criteria
rct vs pct
- measures
- RCT: require data collection outside routine clinical care
- PCT: brief and designed so data can be easily collected in clinical settings
rct vs pct
- results
- RCT: rarely relevant to everyday practice
- PCT: useful in everyday practice, especially clinical decision making
Pragmatic research features
- use EHRs
- randomize treatment alt based on normal health care operations
Comparative effectiveness research
A rigorous evaluation of the impact of different options that are available for treating a given medical condition for a particular set of patients.
drug efficacy vs effectiveness
efficacy: investigates drug ability to have intended effect
effectiveness: investigates if drug achieves its desired effect in the real world
strengths of HMO database
- large, diverse, defined populations
- automated claims, EMR data, access to providers
- varied delivery models and practice patterns
- ability to contact enrollee for participation
weaknesses of HMO database
- absence of population/groups that are uninsured
- smaller fraction of elderly
- meds filled outside of plan, nonrx drugs and inpt dispensing not routinely recorded
strengths of US gov claims database (medicare/medicaid)
- population size and length of follow up
- accuracy of pharmacy claims
- validity of procedure claims
- over-represention of underserved populations
- ability to validate outcomes
- ability to link to external data
weakness of US gov claims database (medicare/medicaid)
- non-representativeness
- unavailable information
- limitations in rx coverage
- eligibility
- data validity/ acess to records
- out of plan care
strengths of hospital databases
- sample size
- versatile data source
- data quality
- efficient
- data longevity
weaknesses of hospital databases
- misclassification
- lack of generalization
- ascertainment bias (different length of stays)
sensitivity vs specificity
how to calculate
- sensitivity: ability of a test to identify correctly those who HAVE the disease; true positive
Sensitivity= TP / (TP+FN) - specificity: ability of a test to identify correctly those who DO NOT HAVE the disease; true negative
Specificity= TN / (TN+ FP)
Morbidity definition and how its described
Rate of disease in a population
- cumulative incidence proportion
- incidence rate
- prevalence
- attack rate
Incidence vs prevalence
how to calculate
- Incidence: number of NEW CASES of a disease during specific period of time in population at risk for developing disease
( # new cases in the population/ # of people at risk of developing disease during that time. ) x 100 - prevalence: number of affected people in the population / number of people in the population x100
what is attack rate
how to calculate
aka outbreaks
- (# of people exposed to virus/bacteria/etc. that then end up getting sick)/ total # of people exposed
mortality rate
number of deaths from a cause in a certain population over a specific period of time
standardization and two types
set of techniques used to remove the effects if differences when comparing populations
- direct: rate of disease/death in STUDY POPULATION assuming dame age distribution
- indirect: compares the rate of death/disease observed to expected rate from STANDARD POPULATION
risk ratios vs odds ratio
how to calculate
- risk: risk of disease in exposed individuals to the risk of unexposed individuals
RR= a/(a+b) / c/(c+d) - odds: ration of the probability of occurrence of an event to that of non-occurrence
OR= (AxD) / (BxC)
characteristics of risk ratio
- chance of outcome/ all possible outcomes
- looks at the total number of people in the population
- prospective, cohort studies
characteristics of odds ratio
- the probability of occurrence of an event/probability of the event not occurring
- looks at those that experience vs did not experience event
- retrospective case control studies
- multiple logistic regression
Attributable risk
- amount of disease incidence or risk that can be attributed to a specific exposure
AR= risk exposed- risk unexposed
ex = cigarette smoke and lung cancer
Population Attributable risk ex
- PAR= 12% in a study assessing the relation between smoking and low birth weight
- making all people in the population stop smoking would eliminate 12% of all cases of low birth weight in the population
confidence intervals
- smaller ranger, more reliable
- if range includes 0 there is no significant change
what is the quadruple aim of health care
- improving population health
- reducing cost of care
- enhancing the patient experience
- improving provider satisification
humanistic outcomes
consequences of disease or treatment on patient QOL
clinical outcomes
medical events that occur as a result of disease or treatment
economic outcomes
direct, indirect, intangible costs compared w/ the consequences of medical treatment alternatives
** multiple perspectives
ex of direct medical cost
medications, supplies, lab test, hospitalization, healthcare professional time
ex of direct non-medical cost
transportation, food, family care, home aids
ex of indirect cost
low wages (morbidity)
income forgone b/c of death
intangible cost
pain, suffering, inconvenience, grief
opportunity cost
lost opportunity, revenue forgone
full vs partial economic eval
- full: encompasses 2 basic characteristics; compare 2 or more treatment alternatives, both the cost and consequence are examined
- partial: only 1 characteristic ^
What is Cost-effective analysis (CEA)
compares alternatives with therapeutic effects measured in natural units ; may differ in clinical outcome but has same unit of benefit
Cost effective treatment alternatives
Less expensive w/ equal effectiveness
More expensive w/ added benefit worth the additional cost
Less expensive and less effective where the added benefit is not worth the cost
what is cost minimization analysis (CMA)
finds the least expensive cost alternative; used when benefits are the same
what is cost of illness (COI)
estimates the cost of a disease on a defined population; can compare prevention vs treatment options
- identifies direct and indirect cost
- provides estimation of financial burden of a disease
what is cost benefit analysis (CBA)
compare cost and benefit of treatment alternatives; program w/ different objectives ; unit is money
