1
(VERIFIED CPH)
CPH EXAM DEFINATIONS SET OF QUESTIONS AND
CORRECT ANSWERS ALREADY GRADED A+
GUARANTEED SUCCESS
Ecological Fallacy
Bias that may occur because an association observed between variables or an
aggregate level does not represent the association that exists at an individual level
MRSA
bacterial strains. resistent to antibiotics. benign colonizers of the skin. may cause
severe infections.
Morbidity
rate of disease, incidence. HOW MANY PEOPLE ARE SICK
Mortality
death rate. PEOPLE WHO HAVE DIED.
Metabolism
conversion or breakdown of a substance from one form to another by a living
organism
Mutagen
agent that causes a permanent genetic change outside of normal growth.
mutagenicity
capacity to cause permanent genetic change
metabolites
substance produced by biological processes
metabolomics
, 2
(VERIFIED CPH)
use of genomic information to facilitate studies of metabolic processes.
Latency
time from 1st exposure until the appearence of a toxic effect.
IRIS (integrated risk information system)
descriptive, quantitative regulatory information on chemicals. health professionals
not experts.
Incidence
# of new cases in a defined population over a specific time period.
hydrophilic
strong affinity for water
hydrophobic
strong aversion for water
Confidence Interval
95% confident that the true value of a variable is contained within the interval.
-used to account for sampling variability
-it is a point estimate +_ margin of error, where the point estimate is the best estimate
of teh unknown parameter and the margin of error is the product of the confidence
level and the standard error.
Clinical Trial Phases
1. Safety and Pharmacologic profiles
2. pilot efficacy studies
3. extensive clinical trials
4. after the FDA approves, look at specific effects to establish incidence of adverse
reactions, etc. longterm use effects.
interpretation of studies
temporality: cause precedes effect
Specificity: important in assessing the possibility of biases.
, 3
(VERIFIED CPH)
Consistency: several studies showing similar results. homogeneity statistically.
Confounders
-non-causal association between exposure and outcome as a result of a third variable.
-distortion of effect by other factors
-must be related to exposure AND outcome
-not an intermediate variable on causal pathway
Controlling for confounders
before data collection: random collection, individual matching, frequency matching
After data collection: direct adjustment, indirect adjustment, mantel-haenszel,
regression techniques
Quality Assurance vs. Quality Control
QA: ensure quality before data collection
QC: monitor and maintain quality during study
reliability vs. validity
R: precision, reproducibility
V: accuracy, absence of bias
systematic error
(lack of validity) if there's a difference between what is actually being estimated and
what is intended to be measured. Increasing sample size doesn't help.
Random Error
(lack of precision) occurs, but increasing sample size helps.
RCT studies
Tests efficacy or effectiveness of healthcare services. random allocation of
participants to different treatments. Includes blinding, placebo. gold standard for
evidence.
Community Intervention/cluster RCT
community-wide basis or groupwide
, 4
(VERIFIED CPH)
Case-Crossover RCT design
-cases serve as their own control
-exposure has transient effect
Cross Sectional Studies
SNAPSHOT! at a single point in time. tells the prevalence and association. causation
cannot be implied. a study that examines the relationship between diseases and other
variables as they exist in a defined population at one particular time.
Matching
used to make cases and controls as similar as possible to avoid confounding. ex:
race, gender, age. +Maybe the only way to control confounding. increases statistical
power, straightforward. -requires use of special analytical techniques, residual
confounding can occur if you match continuous variables by category.
types of matching
individual matching: case and control matched individually
frequency matching: a group of controls
Minimum Euclidean Distance measure: match to closest person.
Cohort Studies
RISK RATIO, RELATIVE RISK, INCIDENCE RATE, RATE RATIO
-rare exposures
-group of subjects who shared experiences during a particular time. Determines if
incidence is related to exposure.
Concurrent/longitudinal cohort studies
starts now (with a baseline exam) and goes into future. expensive and time intensive.
non-concurrent/retrospective cohort studies
assembled in past based on existing records. faster and quicker, but records can be
limited or biased. follow up can be hard.
Prevalence of disease
(VERIFIED CPH)
CPH EXAM DEFINATIONS SET OF QUESTIONS AND
CORRECT ANSWERS ALREADY GRADED A+
GUARANTEED SUCCESS
Ecological Fallacy
Bias that may occur because an association observed between variables or an
aggregate level does not represent the association that exists at an individual level
MRSA
bacterial strains. resistent to antibiotics. benign colonizers of the skin. may cause
severe infections.
Morbidity
rate of disease, incidence. HOW MANY PEOPLE ARE SICK
Mortality
death rate. PEOPLE WHO HAVE DIED.
Metabolism
conversion or breakdown of a substance from one form to another by a living
organism
Mutagen
agent that causes a permanent genetic change outside of normal growth.
mutagenicity
capacity to cause permanent genetic change
metabolites
substance produced by biological processes
metabolomics
, 2
(VERIFIED CPH)
use of genomic information to facilitate studies of metabolic processes.
Latency
time from 1st exposure until the appearence of a toxic effect.
IRIS (integrated risk information system)
descriptive, quantitative regulatory information on chemicals. health professionals
not experts.
Incidence
# of new cases in a defined population over a specific time period.
hydrophilic
strong affinity for water
hydrophobic
strong aversion for water
Confidence Interval
95% confident that the true value of a variable is contained within the interval.
-used to account for sampling variability
-it is a point estimate +_ margin of error, where the point estimate is the best estimate
of teh unknown parameter and the margin of error is the product of the confidence
level and the standard error.
Clinical Trial Phases
1. Safety and Pharmacologic profiles
2. pilot efficacy studies
3. extensive clinical trials
4. after the FDA approves, look at specific effects to establish incidence of adverse
reactions, etc. longterm use effects.
interpretation of studies
temporality: cause precedes effect
Specificity: important in assessing the possibility of biases.
, 3
(VERIFIED CPH)
Consistency: several studies showing similar results. homogeneity statistically.
Confounders
-non-causal association between exposure and outcome as a result of a third variable.
-distortion of effect by other factors
-must be related to exposure AND outcome
-not an intermediate variable on causal pathway
Controlling for confounders
before data collection: random collection, individual matching, frequency matching
After data collection: direct adjustment, indirect adjustment, mantel-haenszel,
regression techniques
Quality Assurance vs. Quality Control
QA: ensure quality before data collection
QC: monitor and maintain quality during study
reliability vs. validity
R: precision, reproducibility
V: accuracy, absence of bias
systematic error
(lack of validity) if there's a difference between what is actually being estimated and
what is intended to be measured. Increasing sample size doesn't help.
Random Error
(lack of precision) occurs, but increasing sample size helps.
RCT studies
Tests efficacy or effectiveness of healthcare services. random allocation of
participants to different treatments. Includes blinding, placebo. gold standard for
evidence.
Community Intervention/cluster RCT
community-wide basis or groupwide
, 4
(VERIFIED CPH)
Case-Crossover RCT design
-cases serve as their own control
-exposure has transient effect
Cross Sectional Studies
SNAPSHOT! at a single point in time. tells the prevalence and association. causation
cannot be implied. a study that examines the relationship between diseases and other
variables as they exist in a defined population at one particular time.
Matching
used to make cases and controls as similar as possible to avoid confounding. ex:
race, gender, age. +Maybe the only way to control confounding. increases statistical
power, straightforward. -requires use of special analytical techniques, residual
confounding can occur if you match continuous variables by category.
types of matching
individual matching: case and control matched individually
frequency matching: a group of controls
Minimum Euclidean Distance measure: match to closest person.
Cohort Studies
RISK RATIO, RELATIVE RISK, INCIDENCE RATE, RATE RATIO
-rare exposures
-group of subjects who shared experiences during a particular time. Determines if
incidence is related to exposure.
Concurrent/longitudinal cohort studies
starts now (with a baseline exam) and goes into future. expensive and time intensive.
non-concurrent/retrospective cohort studies
assembled in past based on existing records. faster and quicker, but records can be
limited or biased. follow up can be hard.
Prevalence of disease
