Term
|
Definition
| the study of how disease is distributed in populations and the factors that influence or determine this distribute; application of this study is to prevent and control health problems |
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Term
| the study of epidemiology |
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Definition
| involves sound methods of investigation; methods rely on careful observation and the use of valid comparison groups to determine whether the observed health events differ from what might be expected |
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Term
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Definition
| study of frequency and pattern of health events in the population |
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Term
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Definition
| number in relation to the population |
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Term
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Definition
| health-related state of event by person, place, and time characteristics |
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Term
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Definition
| search for causes and other factors of health-related states or events |
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Term
| health-related states or events |
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Definition
| disease states (cholera, influenza), conditions associated with health (physical health, nutrition), events (injury, drug abuse, suicide) |
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Term
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Definition
| cause of a disease and the relevant risk factors- factors that increase a persons risk for a disease |
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Term
| objectives of epidemiology |
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Definition
| 1) identify etiology (cause, risk factors) 2) determine the extent of disease in community (quantify problem by counting) 3) study natural history and prognosis of disease (define baseline 4) evaluate preventative/therapeutic measures and modes of healthcare delivery 5) develop public policy by providing data used as rationale for programs |
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Term
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Definition
| answering the who, what, when, and where questions is prerequisite to effective education, screening, prevention, and control programs; provides policy makers with info that can be used for effective allocation of scarce health resources |
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Term
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Definition
| involves identifying and quantifying associations, testing, hypotheses, and identifying causes of health-related states or events; explains why and how health-related states or events occur |
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Term
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Definition
| increased since 1990 (antibiotics, behavior change, hygiene, decrease in child mortality); women have higher life expectancy |
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Term
| what primarily accounts for increase in remaining years of life at birth? |
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Definition
| decrease in infant mortality and childhood diseases |
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Term
| why should we use epi to identify high risk groups? |
|
Definition
1) identification --> direct preventive efforts ex. screening
2) identify specific factors/characteristics --> modification of these factors |
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Term
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Definition
preventing the initial development of disease
ex. immunization, sanitation, education, media campaigns, warning labels
*does not yet have disease, prior to exposure |
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Term
| active primary prevention |
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Definition
requires behavior change on part of subject
-wearing protective devices
-health promotion
-lifestyle changes |
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Term
| passive primary prevention |
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Definition
does not require behavior change
-vitamin fortified foods
-fluoridation of public water supplies |
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Term
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Definition
early detection of existing disease to reduce severity and complications ex. screening for cancer
-disease has already begun, but have no yet developed clinical symptoms of illness |
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Term
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Definition
reducing the impact of the disease
ex. rehab for stroke, halfway houses for alcoholics
-have developed signs and symptoms and have been diagnosed |
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Term
| epidemiology in clinical practice |
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Definition
-diagnosis
-prognosis
-treatment
-practicing medicine: population-based probability |
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Term
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Definition
1) exposure associated with disease?
2) if yes, does E cause D?
-description of data: do we see a difference? are they real? what is responsible for differences? |
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Term
| population-based prevention approach |
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Definition
a preventive measure is widely applied to an entire population
ex. advice against smoking towards entire population
"public health approach" |
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Term
| high risk prevention approach |
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Definition
target a high risk group with a preventive measure
ex. screening for cholesterol in children restricted to children from high risk families
*more expensive
*more invasive/inconvenient |
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Term
| randomized clinical trials |
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Definition
| used to study effects of a treatment in large groups of patients; ideal means to identify appropriate therapy |
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Term
| identifying the cause of a disease |
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Definition
| 1) determine if an association exists between exposure to a factor of a characteristic of a person and development of disease 2) infer about possible causality from patterns of association found |
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Term
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Definition
| involves secondary and tertiary prevention |
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Term
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Definition
| results from an interaction of the host (a person), the agent (ex-bacterium) and the environment (ex-contaminated water supply) |
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Term
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Definition
| person to person by means of direct contact |
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Term
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Definition
| occurs through a common vehicle such as contaminated air or water supply, or by a vector such as a mosquito ex. water to human, vector to human, door knobs |
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Term
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Definition
| characterized by signs and symptoms |
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Term
|
Definition
| disease that is not yet clinically apparent, but is destined to progress to clinical disease *exposed but no activity |
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Term
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Definition
not clinically apparent and is not destined to become clinically apparent. this type of disease often diagnosed by serologic (antibody) response or culture of the organism.
*underlying activity but no symptoms manifested |
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Term
| persistent (chronic) disease |
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Definition
person fails to "shake off" the infection, and it persists for years, at times for life.
ex. HBV |
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Term
|
Definition
an infection with no active multiplication of agent, only genetic message is present in the host, not the viable organism
*HIV |
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Term
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Definition
| individual harbors the organisms, but not infected as measured by serologic studies (no evidence of an antibody response) or by evidence of clinical illness |
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Term
|
Definition
| habitual presence of a disease within a given geographic area |
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Term
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Definition
| occurrence in a community or region of group of illnesses of similar nature, clearly in excess of normal expectancy, and derived from common or propagated source |
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Term
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Definition
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Term
|
Definition
| if outbreak occurs in group of people who have eaten food because all the causes the developed were in persons exposed to food in question |
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Term
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Definition
| eating questionable food once |
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Term
|
Definition
| eating food more than once |
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Term
| single exposure, common vehicle outbreak |
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Definition
*common
-explosive
-limited to common exposure |
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Term
|
Definition
resistance of a group of people to an attack by a disease to which a large proportion of the members of the group are immune
*group not susceptible to disease |
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Term
| when does herd immunity happen? |
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Definition
| if the probability of an infected person encountering every other individual in the population (random mixing) |
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Term
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Definition
| interval from receipt of infection to the time of onset of clinical illness |
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Term
| what accounts of incubation period? |
|
Definition
1) time needed to replicate
2) site in the body
3) does of infectious agent received |
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Term
| 3 critical variables in investigating an outbreak or epidemic |
|
Definition
1) when did exposure take place?
2) when did disease begin?
3) what was the incubation period for disease? |
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Term
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Definition
*incident rate
*useful for comparing risk of disease in groups with different exposures
(became sick/ sick +well) x 100 |
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Term
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Definition
| person who acquires disease from that exposure (contaminated food) |
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Term
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Definition
| acquires disease from exposure to primary case |
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Term
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Definition
*measure of contagiousness
*measures infectivity of the agent and effect of vaccine
attack rate of susceptible people who have been exposed to primary case
(total # of cases-initial cases/ # of susceptible persons-initial cases) x 100 |
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Term
| how to investigate occurrence? |
|
Definition
-who was attacked by disease?
-when did disease occur?
-where did cases arise? |
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Term
|
Definition
# of deaths caused by a disease among those who have the disease
(# of deaths due to disease X)/ # of cases of disease X) x 100 |
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Term
| factors associated with the initiation of an investigation |
|
Definition
-severity of illness
-potential for spread
-political considerations
-public concern
-resources |
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Term
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Definition
| how fast the disease is occurring |
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Term
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Definition
| what fraction of population is affected |
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Term
|
Definition
number of new cases of a disease that occur during a specified time period in a population at risk for developing disease
(# of new cases occurring/ # of people at risk for disease) x 1,000 |
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|
Term
| when all people are not observed for the full time period |
|
Definition
calculate incidence rate where denominator consists of sum of the units of time that each individual was at risk and was observed
*person-time
ex. person-years |
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Term
|
Definition
number of people exposed to a suspect food who became ill/ number of people who were exposed to that food
*actually a proportion more than a rate |
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Term
|
Definition
(# of affected persons present in population at a specified time/ # of persons in population at that time) x 1,000
*numerator includes a mix of people with different durations of disease ---> do not have a measure of risk |
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Term
|
Definition
| cases are limited to those who share a common exposure ex. foodborne, water |
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Term
|
Definition
| disease often passed from one individual to another ex. measles, STDs |
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Term
|
Definition
| prevalence of disease at a certain point in time |
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Term
|
Definition
| how many people have had the disease at any point during a certain time period |
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Term
|
Definition
1) point prevalence 'do you currently have x'
2) period prevalence 'have you had x during the last n years'
3) cumulative incidence 'have you ever had x' |
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Term
|
Definition
1) defining who has disease
2) ascertaining which persons should be included in numerator |
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Term
| problem with denominators |
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Definition
1) selective undercounting of certain groups in population
2) everyone in denom group must have potential to enter the group that is represented by numerator |
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Term
| problems with hospital data |
|
Definition
-admissions are selective
-records not designed for research
-problem defining denom because hospital do not have catchment areas |
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Term
| relationship between incidence and prevalence |
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Definition
| prevalence= incidence x duration of disease |
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Term
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Definition
| may be carried out to monitor changes in diseases in frequency or to monitor changes in prevalence of risk factors |
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Term
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Definition
| either available data on reportable diseases are sued or reporting is mandated or requested with the responsibility for the reporten often falling on health care provider |
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Term
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Definition
| project staff make periodic field visits to health care facilities such as clinics and hospitals to identify new cases of a disease or diseases of deaths from disease that have occurred |
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Term
|
Definition
| measured to establish priorities for scarce health resources |
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Term
| steps in an outbreak investigation |
|
Definition
1) define problem: signs and symptoms that characterize illness
2) examine distribution of case- person, place, time (look at shape/length of plot to determine incubation time and propagated source, look at ARs and RR)
3) form hypothesis- RR
4) test hypothesis and explain outliers
5) draw conclusions/formulate practical applications
***see slides chapter 2 |
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|
Term
|
Definition
simplest and most frequently performed quantitative measure in epi
-refers to the # of cases of a disease or other health phenomenon being studied
-significant for rare diseases or symptom presentations (case of ebola virus) |
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Term
|
Definition
value obtained by dividing one quantity by another
-most general form has no specified relationship between numerator and denominator
-proportions, rates, and percentages are also ratios |
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Term
|
Definition
| ratio that consists of a numerator and a denominator in which time forms part of a denominator |
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|
Term
| interpretation of prevalence |
|
Definition
provides indication of the extent of a health problem
*proportion, not rate
*estimates frequency of exposure
*determines allocation of health resources |
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Term
| if duration of disease is short and incidence is high.... |
|
Definition
prevalence becomes similar to incidence
*short duration-- cases recover rapidly or are fatal |
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Term
| if duration of disease is long and incidence is low... |
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Definition
prevalence increases greatly relative to incidence
ex- many chronic diseases |
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Term
|
Definition
| (total # of deaths from all causes in 1 year/ # of persons in population at midyear) x 1,000 |
|
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Term
| measure disease occurrence |
|
Definition
| a quantitative measure to look at differences in the risk of dying from a disease |
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Term
|
Definition
(# of individuals dying during a specified time period after disease onset or diagnosis/ # of individuals with this specified disease) x 1,000
*denominator limited to those who already have a disease |
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Term
|
Definition
| (# of deaths among X age/ # of people X age) x 100,000 |
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Term
|
Definition
| (mortality of given disease/ population size at midyear) x 100,000 |
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Term
|
Definition
*not a rate
*indicates relative importance of a specific cause of death; not a measure of the risk of dying of a particular cause
(# of deaths from X disease in 2000/ total # of deaths in US in 2000) x 100 |
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Term
|
Definition
| index of severity of a disease, can also be used as an index of risk of disease |
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Term
| years of potential life lost (YPLL) |
|
Definition
measure of premature mortality--early death
3 public health functions:
1) establish research priority
2) surveillance of time trends in premature death
3) evaluate effectiveness of interventions
*YPLL for each person to yield total YPLL for a specific cause of death |
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Term
| problems with mortality data |
|
Definition
most info comes from death certificates
*countries vary in quality of data provided
*changes in disease definition can have effect |
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Term
|
Definition
allow for comparison of mortality data in 2 or more populations or one population over different time points
*population may differ by characteristics that affect mortality |
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Term
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Definition
| not adjusted for age, gender, etc |
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Term
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Definition
| death rates by age per 1,000 population |
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Term
|
Definition
stand population used in order to eliminate the effects of any differences in age between 2 or more populations being compared
*hypothetical because they involve applying actual age-specific rates to hypothetical/standard population |
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Term
|
Definition
often used when number of deaths for each age-specific stratum are not available
*used to study mortality in an occupationally exposed population
*presented as SMR |
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|
Term
| standardized mortality ratio (SMR) |
|
Definition
observed # of deaths per year/ expected # of deaths per year
*requires age structure of study population
*total # of outcomes in study population
*age-specific rates for a standard pop
= 100 --> no difference in outcomes
> 100 --> increase risk in study pop
< 100 --> decrease risk in study pop |
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Term
| standardization for indirect adjustment |
|
Definition
not appropriate to compare SMRs between studies- only to the standard pop
-direct standardization is preferred over indirect
-indirect: 1) used traditionally in PH 2) used to compare general pop 2) intuitive and easy to understand |
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Term
|
Definition
estimate economic burden of disease
-plan health services
advantage: actual summary rates
dis: difficult to interpret because of differences in population structures |
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Term
|
Definition
compare rates among subpopulations or for various causes
advantage: homogenous subgroups, detailed info
dis: cumbersome if many subgroups, no summary figure |
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Term
|
Definition
compare health of entire population because allow for comparison of populations with different demographic structures
advantage: provide a summary figure, control confounders, permits group comparison
dis: fictional rate, magnitude depends on population standard, hides subgroup difference |
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Term
|
Definition
| testing asymptomatic individuals who are at high risk due to demographic profile, occupation, etc |
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Term
|
Definition
| physical exam, evaluation of lab test applied to high risk but asymptomatic people to reveal presence or absence of an early form of disease (Detectable, Pre-Clinical, Phase, or DPCP of disease) |
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Term
|
Definition
| test applied to people having signs or symptoms and therefore presumed to have disease but confirmation is needed |
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Term
|
Definition
| column 1 calculation of those people in DPCP, proportion who test positive as they should be (a/a+c) |
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Term
|
Definition
| column 2 calculation of those people not in the DPCP, the proportion test-negative as they should (d/b+d) |
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Term
|
Definition
row 1 calculation of those people who test positive, proportion diagnosed with disease on follow up exam (a/a+b)
(disease/total positive) |
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Term
|
Definition
| row 3, proportion of screenees in the DPCP at time of screening (a+c/n) |
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Term
|
Definition
| group of people who have the same experience |
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Term
| possible explanations of trends or differences in mortality |
|
Definition
-change in survivorship without change in incidence
-change in incidence
-change in age composition of the populations
-combo of above |
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Term
|
Definition
| its ability to distinguish between who has a disease and who does not |
|
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Term
|
Definition
| ability of a test to identify correctly those who have disease |
|
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Term
|
Definition
| ability of a test to identify correctly those who do have the disease |
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Term
| negative predictive value |
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Definition
|
|
Term
| relationship between PPV and specificity |
|
Definition
| disease/total--> includes specificity |
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Term
|
Definition
| incidence of a disease in a population |
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Term
| design of a randomized clinical trial |
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Definition
| study pop--> random assigment---> 1) current treatment 2) new treatment---> 1) improve/did not improve 2) improve/did not improve |
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Term
|
Definition
| defined population --> nonrandomized--> 1) exposed 2) not exposed---> 1) disease/no disease 2) disease/no disease |
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Term
|
Definition
| disease risk in exposed/disease risk in unexposed |
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Term
|
Definition
| disease risk in exposed- disease risk in nonexposed |
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Term
|
Definition
risk in exposed/risk in unexposed
= 1 --> no evidence for increased risk
<1 --> negative association ex. vaccine
>1 --> positive association *may be causal |
|
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Term
| relative risk in cohort studies |
|
Definition
can be calculated directly
(a/a+b)/(c/c+d) |
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Term
|
Definition
ratio of the odds of development of disease in exposed persons to the odds of development of disease in nonexposed
ad/bc |
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Term
| odds ratio in case control study |
|
Definition
ad/bc
= 1 --> no association
> 1--> positive
<1--> negative |
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|
Term
| when is OR a good estimate of RR? |
|
Definition
1. when cases are representative of people with disease
2. when controls are representative with regard to exposure for people without disease
3. when disease does not occur frequently |
|
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Term
| odds ration in a matched pairs case control |
|
Definition
ratio of discordant pairs
*ratio of # of pairs in which case was exposed and control was not, to the # of pairs in which control was exposed and case was not
= b/c |
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Term
|
Definition
| incidence in exposed group- incidence in unexposed |
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Term
| proportion of total incidence in exposed group (attributable risk) |
|
Definition
| incidence of exposed-incidence of unexposed/incidence of exposed |
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|
Term
| population attributable risk |
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Definition
incidence in total population- incidence in nonexposed group
proportion: incidence total pop-incidence in nonexposed/incidence total pop |
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|
Term
| 3 core functions of public health |
|
Definition
1. assessment
2. policy development
3. assurance |
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Term
|
Definition
-monitor health status to identify community health problems
-diagnose and investigate health problems and health hazards in community
-evaluate effectiveness, accessibility, and quality of personal and population-based health services |
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Term
|
Definition
-develop policies and plans that support individual and community health efforts
-enforce laws and regulations that protect health and ensure safety
-research for new insights and innovative solutions to health problems |
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Term
|
Definition
-link people to needed personal health services and assure the provision of health care when otherwise unavailable
-assure a competent public health and personal healthcare workforce
-inform, educate, and empower people about health issues
-mobilize community partnerships to identify and solve health problems |
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Term
|
Definition
maintain greatest control
ex. RCT ex. clinical trial
-test efficacy of exposure
-test etiologic hypotheses and estimate long-term effects
-test effects of intervention to alter health status |
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Term
| community intervention (experimental) |
|
Definition
-potential to greatly impact population's health
-typically oriented towards education and behavior change at population level
ex. smoking cessation
weight gain prevention |
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Term
| quasi-experimental studies |
|
Definition
-manipulation of exposure but no randomization
-natural experiments
-used to evaluate impact of PH programs and policies
ex. compare traffic fatalities in states with and without seat belt laws |
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Term
|
Definition
-some cases experiments may be impractical or unethical
-no manipulation or exposure or randomization
-careful measurement of patterns of exposure and disease |
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Term
|
Definition
| driven by hypothesis determined in advance to justify study approach |
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Term
|
Definition
-no advance hypotheses
-available data to exposure existing patterns of disease |
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Term
|
Definition
-case reports
-case series
-cross sectional surveys
-accepts associations may not be causal
-hypothesis can be further tests
-employes preexisting data
used to:
-depict individual's health characteristics with respect to person, place, time
-estimate disease frequency and time trends
-health planning and resource allocation |
|
|
Term
|
Definition
-ecological studies
-case control
-cohort
-hypotheses proposes causal link
-requires new data collection of the exposure of interest
used to:
-test specific hypothesis
-generate new hypothesis
-suggest mechanism of causation |
|
|
Term
| common sequence of studies |
|
Definition
1. case reports
2. descriptive studies
3. analytic studies
-recognize a problem
-hypothesis generating
-testing hypothesis E---> D |
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|
Term
| cross sectional approach 2x2 |
|
Definition
disease
A B A+B-->exposure
C D C+D
A+C B+D N |
|
|
Term
|
Definition
disease
A B A+B
C D C+D-->exposure
A+C B+D |
|
|
Term
|
Definition
disease
A B A+B
C D C+D-->exposure
A+C B+D |
|
|
Term
|
Definition
disease
A B A+B
C D C+D---> exposure
A+C B+D |
|
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Term
|
Definition
-individual cases of unusual disease or symptoms are described in terms of personal characteristics
*recognizing new diseases or sudden change in disease patterns |
|
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Term
|
Definition
-examines a group as a unit of analysis
used to: generate hypothesis in analytic studies |
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Term
|
Definition
-potential study participants are sampled according to current outcome status
-questionnaire used to ascertain exposure in the past
-comparison made between cases and controls (free of disease)
-retrospective |
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Term
|
Definition
potential study participants are sampled based on exposure status (free of disease at baseline)
ex. smoker vs nonsmoker
-observed for a period of follow up
-prospective, retrospective |
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Term
|
Definition
-intervention study-investigators dictate which participants are exposed
-random assignment
-prospective
-superior control over confounds
-estimates incidence
-study several outcomes |
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Term
|
Definition
|
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Term
|
Definition
risk probability of an event occurring
-questions of etiology--cohort studies, case control |
|
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Term
|
Definition
risk ratio
-determine whether a certain disease is associated with a certain exposure |
|
|
Term
|
Definition
| probability of an event occurring among exposed/ probability of event occurring among unexposed |
|
|
Term
|
Definition
odds that case was exposed/odds control was exposed
ad/bc |
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Term
|
Definition
cohort: RR or OR can be used
case control: OR is used to approximate RR
-valid when case and controls are representative
-disease is rare |
|
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Term
|
Definition
RR-etiology
AR- potential for prevention |
|
|
Term
|
Definition
| incidence rate in unexposed |
|
|
Term
|
Definition
| incidence rate in exposed |
|
|
Term
|
Definition
population attributable risk proportion
[(p(r-1))/(p(r-1))+1)] |
|
|
Term
| things to consider when evaluating a screening program |
|
Definition
-can disease be detected early?
-what are SN and SP of test?
-PPV of test?
-how serious is false-positive test result?
-cost?
-harmful?
-is there an overall benefit? |
|
|
Term
| assessing effectiveness of screening: operational measures |
|
Definition
-number of people screened
-proportion of populated screened/# of times
-detected prevalence of preclinical disease
-total cost
-cost per case found
-cost per previously unknown case found
-proportion + screenees brought to final diagnosis/treatment
-predictive value of positive test in population screened |
|
|
Term
| assessing effectiveness of screening: outcome measures |
|
Definition
-reduction of mortality in population screened
-reduction of CFR in screened individuals
-increase in percent of cases detected early
-reduction in complications
-prevention of or reduction in recurrences or metastases
-improvement of quality of life in screened individuals |
|
|
Term
| natural history of disease |
|
Definition
*see slide diagram
-biological onset of disease is usually undetectable
-later, clinical signs prompt patient to seek care, diagnosis is made, and proper treatment is given |
|
|
Term
| natural history: preclinical phase |
|
Definition
| the period for biological onset of disease to the development of signs and symptoms |
|
|
Term
| natural history: clinical phase |
|
Definition
| the period from when signs and symptoms develop to an ultimate outcome |
|
|
Term
| screenings major challenge |
|
Definition
| identifying people with disease who are asymptomatic (in preclinical phase) |
|
|
Term
| detectable preclinical phase |
|
Definition
| the interval from the point where preclinical phase can be detected to the development of signs and symptoms |
|
|
Term
|
Definition
| interval by which the time of diagnosis is advanced by screening and early detection compared to the usual time diagnosis |
|
|
Term
|
Definition
| point in natural history before treatment is more effective and/or less difficult to administer |
|
|
Term
| referral bias (volunteer bias) |
|
Definition
type of selection bias
-differences between those who participate in screening and those who do not
-scenario 1: people with better prognosis are more likely to be referred for screening
-scenario 2: many people who are at high risk of disease volunteer for screening because they are worried about family history
-best addressed by carrying out randomized experimental study where 2 groups have similar initial prognostic profiles |
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Term
| length-biased sampling (prognostic selection) |
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Definition
type of selection bias
-does not relate to who comes for screening but rather to type of disease that is detected by screening
-do cases found have better natural history regardless of how early therapy is initiated? |
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Term
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Definition
screening tends to selectively identify those cases with longer preclinical phases (better prognosis)
-these people would have better prognosis even if there were no true benefits from screening |
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Term
| possible outcomes of screening program |
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Definition
*lead time bias
A- usual time of diagnosis--> usual time of death
B- earlier diagnosis--> usual time of death
C- earlier diagnosis--> delayed death
D- earlier diagnosis --> no death from disease |
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Term
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Definition
| the illusion of better survival only because of earlier detection |
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Term
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Definition
-when comparing screened and unscreened population, we must estimate lead time
-if early detection is truly associated with improved survival, survival in the screened group should be greater than survival in the unscreened group plus the lead time |
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Term
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Definition
-type of misclassification bias
-occurs were disease free individuals are diagnosed with disease (false positive)
-healthy people have good survival. thus, the more overdiagnosis there is, the better survival appears
-results in an inflated estimate of survival and an incorrect conclusion that screening improves survival |
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Term
| avoiding overdiagnosis bias |
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Definition
| always use a standardized diagnostic process or case definition to minimize potential of misclassifying patients |
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Term
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Definition
| 1) advanced disease--> screened in past/never screened 2) controls---> screened in past/never screened |
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Term
| screening for cervical cancer |
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Definition
-pap smear one of most widely used screening tests
-widely accepted as effective
-direct cost is over $1.7 billion per year
-no conclusive evidence that pap smears are effective (no properly designed RCT of cervical cancer screening) |
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Term
| approaches for evaluating screening for cervical cancer |
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Definition
1. compare incidence and mortality rates with different rates of screening
2. examine changes over time in rates of diagnosis of carcinoma in situ
3. case-control study where frequency of past pap smears is compared between women with invasive cervical cancer and controls
-all subject to the methodologic |
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Term
| neuroblastoma screening: pros and cons |
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Definition
-aspects of illness constitute a strong rationale for screening
-many tumors regress spontaneously, without treatment
-screening more likely to detect slow growing tumors than aggressive ones |
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Term
| cost benefit analysis of screening |
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Definition
cost effectiveness includes not only financial costs, but also nonfinancial costs to patient (anxiety, inconvenience)
-is test invasive?
-if test is positive, is invasive therapy warranted by test result?
-what is false positive rate? |
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Term
| ACS recommendations on cancer related screening |
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Definition
1. must be good evidence that each test or procedure recommended is medically effective in reducing morbidity or mortality
2. medical benefits must outweigh risks
3. cost of each test or procedure must be reasonable compared with its expected benefits
4. recommended actions must be practical and feasible |
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