Gordis Chapter 14,15,18, 5
Epidemiology Test Questions and
Answers.
Bias - Answer Showing an unfair tendency to believe that some people, ideas are better than
others
Selection Bias - Answer Error due to systematic differences in exposures between those who
are selected and those who are not (deals with exposed/unexposed AND cases/non-cases)
Prevention and control of bias can be accomplished at 3 levels - Answer 1. Ensuring that the
study design is appropriate for addressing the study hypotheses
2. Establishing and carefully monitoring procedures of data collection that are valid and reliable
3.Using appropriate analytic procedures
Unbiased - Answer Free from all prejudice and favoritism; fair
Exclusion bias - Answer When investigators apply different eligibility criteria to the cases and
to the controls in regard to which clinical conditions in the past would permit eligibility in the
study and which would serve as the basis for exclusion.
Misclassification of exposure is non-differential - Answer if the misclassification is unrelated to
the occurrence or presence of disease.
Misclassification of exposure is differential - Answer if the misclassification is different for
those with and without disease.
Misclassification of disease is non-differential - Answer if the misclassification is unrelated to
exposure.
Misclassification of disease is differential - Answer if the misclassification is different for those
with and without exposure.
, Misclassification of outcome - Answer Some people who have the disease (true cases) may be
misclassified as non-cases, and some without disease (true non-cases) may be classified as
cases.
Information bias - Answer Results from a systematic tendency for individuals selected for
inclusion in the study to be erroneously placed in different exposure/outcome categories, thus
leading to misclassification.
Information bias is equally likely in both - Answer prospective and retrospective studies.
What is inference? - Answer The act of passing from statistical sample data to
generalizations (as of the value of population
parameters) usually with calculated degrees of
certainty
The process of passing from observations and
axioms to generalizations
Inductive reasoning - Answer "Any method of logical reasoning that proceeds from the
particular to the general
Deductive reasoning - Answer Reasoned argument proceeding from the general to the specific
What is an Association? - Answer Statisical dependence between two or more events,
charateristics or other variables/ A property of a dataset.
A fault‐free mathematical property of a dataset.
What defines Cause? - Answer An event, condition, or characteristic that preceded the disease
event and w/o which the disease wouldn't have occurred at all, or wouldn't have occurred until
some later time
Categorization of Risk Factors - Answer 1. Non-modifiable - inherent factors in the individual
Ex. Genetics
Epidemiology Test Questions and
Answers.
Bias - Answer Showing an unfair tendency to believe that some people, ideas are better than
others
Selection Bias - Answer Error due to systematic differences in exposures between those who
are selected and those who are not (deals with exposed/unexposed AND cases/non-cases)
Prevention and control of bias can be accomplished at 3 levels - Answer 1. Ensuring that the
study design is appropriate for addressing the study hypotheses
2. Establishing and carefully monitoring procedures of data collection that are valid and reliable
3.Using appropriate analytic procedures
Unbiased - Answer Free from all prejudice and favoritism; fair
Exclusion bias - Answer When investigators apply different eligibility criteria to the cases and
to the controls in regard to which clinical conditions in the past would permit eligibility in the
study and which would serve as the basis for exclusion.
Misclassification of exposure is non-differential - Answer if the misclassification is unrelated to
the occurrence or presence of disease.
Misclassification of exposure is differential - Answer if the misclassification is different for
those with and without disease.
Misclassification of disease is non-differential - Answer if the misclassification is unrelated to
exposure.
Misclassification of disease is differential - Answer if the misclassification is different for those
with and without exposure.
, Misclassification of outcome - Answer Some people who have the disease (true cases) may be
misclassified as non-cases, and some without disease (true non-cases) may be classified as
cases.
Information bias - Answer Results from a systematic tendency for individuals selected for
inclusion in the study to be erroneously placed in different exposure/outcome categories, thus
leading to misclassification.
Information bias is equally likely in both - Answer prospective and retrospective studies.
What is inference? - Answer The act of passing from statistical sample data to
generalizations (as of the value of population
parameters) usually with calculated degrees of
certainty
The process of passing from observations and
axioms to generalizations
Inductive reasoning - Answer "Any method of logical reasoning that proceeds from the
particular to the general
Deductive reasoning - Answer Reasoned argument proceeding from the general to the specific
What is an Association? - Answer Statisical dependence between two or more events,
charateristics or other variables/ A property of a dataset.
A fault‐free mathematical property of a dataset.
What defines Cause? - Answer An event, condition, or characteristic that preceded the disease
event and w/o which the disease wouldn't have occurred at all, or wouldn't have occurred until
some later time
Categorization of Risk Factors - Answer 1. Non-modifiable - inherent factors in the individual
Ex. Genetics
