Chapter 1- Introduction to Medical
Research exam with complete solutions
Biostatistics/Biometrics - ANSWER- refer
s to the application of statistics in the health-related fields
Clinical Epidemiology/Evidence-Based Medicine - ANSWER- the application of
population-based information to decision making about individual patients
Observational Studies - ANSWER- studies in which the subjects are observed
- case report
-case-series (descriptive)
- case-control (retrospective)
- cross-sectional, surveys (prevalence)
- cohort
Experimental Studies - ANSWER- studies in which some INTERVENTION is performed
- controlled trials
- studies with no controls
Intervention - ANSWER- an investigator-controlled maneuver, such as a drug, a
procedure, or a treatment
Case Report - ANSWER- usually describe an individual patient
- often used to describe an adverse event, rare disease, or uncommon presentation of a
disease
- an interesting patient -- leads to desire to know more
Case-Series Studies (Descriptive) - ANSWER- simple descriptive account of interesting
characteristics observed in a group of patients
- descriptive study -- records of events
- often derived by reviewing charts
Limitations of Case-Series Studies - ANSWER- - cause of the event may not be identified
- sample may not be indicative of the general population
Advantages of Case-Series Studies - ANSWER- - provide a basis for future research
, - qualitative measure of success and may identify unknown areas of concern
- low cost
Longitudinal Studies - ANSWER- a study that takes place over an extended period of time
Control Subjects - ANSWER- - clinical trial -- subjects assigned to the placebo or control
condition
- case-control study -- subjects without the disease or outcome
Case-Control Studies (Retrospective) - ANSWER- begin with the absence or presence of
an outcome and then look backward in time to try to detect possible causes or risk
factors that may have been suggested in a case-series report
- the CASES are individuals selected on the basis of some disease or outcome
- the CONTROLS are individuals without the disease or outcome
- the history or previous events of both cases and controls are analyzed in an attempt to
identify a characteristic or risk factor present in the cases' histories but not in the
controls' histories
- outcome --> possible cause or risk factor
Retrospective Studies - ANSWER- study undertaken in a post hoc manner, ie, after the
observations have been made
Matching - ANSWER- - process of making two groups homogenous on possible
confounding factors
Limitations of Case-Control Studies - ANSWER- - recall bias
- cannot show contributory cause -- cannot show that altering the cause will alter the
effect
Advantages of Case-Control Studies - ANSWER- - good for screening for potential risk
factors -- can look at multiple at once, suggest new hypothesis
- helpful for rare diseases
- inexpensive, easy, fast
Cross-Sectional Studies, Surveys (Prevalence) - ANSWER- - analyze data collected on a
group of subjects at one time rather than over a period of time
- designed to determine "what is happening?" right now
Prevalence - ANSWER- proportion of people who have a given disease or condition at a
specified point in time
Blind Studies - ANSWER- - experimental study in which subjects do not know the
treatment they are receiving
- investigators may also be blind to the treatment subjects they are receiving
Research exam with complete solutions
Biostatistics/Biometrics - ANSWER- refer
s to the application of statistics in the health-related fields
Clinical Epidemiology/Evidence-Based Medicine - ANSWER- the application of
population-based information to decision making about individual patients
Observational Studies - ANSWER- studies in which the subjects are observed
- case report
-case-series (descriptive)
- case-control (retrospective)
- cross-sectional, surveys (prevalence)
- cohort
Experimental Studies - ANSWER- studies in which some INTERVENTION is performed
- controlled trials
- studies with no controls
Intervention - ANSWER- an investigator-controlled maneuver, such as a drug, a
procedure, or a treatment
Case Report - ANSWER- usually describe an individual patient
- often used to describe an adverse event, rare disease, or uncommon presentation of a
disease
- an interesting patient -- leads to desire to know more
Case-Series Studies (Descriptive) - ANSWER- simple descriptive account of interesting
characteristics observed in a group of patients
- descriptive study -- records of events
- often derived by reviewing charts
Limitations of Case-Series Studies - ANSWER- - cause of the event may not be identified
- sample may not be indicative of the general population
Advantages of Case-Series Studies - ANSWER- - provide a basis for future research
, - qualitative measure of success and may identify unknown areas of concern
- low cost
Longitudinal Studies - ANSWER- a study that takes place over an extended period of time
Control Subjects - ANSWER- - clinical trial -- subjects assigned to the placebo or control
condition
- case-control study -- subjects without the disease or outcome
Case-Control Studies (Retrospective) - ANSWER- begin with the absence or presence of
an outcome and then look backward in time to try to detect possible causes or risk
factors that may have been suggested in a case-series report
- the CASES are individuals selected on the basis of some disease or outcome
- the CONTROLS are individuals without the disease or outcome
- the history or previous events of both cases and controls are analyzed in an attempt to
identify a characteristic or risk factor present in the cases' histories but not in the
controls' histories
- outcome --> possible cause or risk factor
Retrospective Studies - ANSWER- study undertaken in a post hoc manner, ie, after the
observations have been made
Matching - ANSWER- - process of making two groups homogenous on possible
confounding factors
Limitations of Case-Control Studies - ANSWER- - recall bias
- cannot show contributory cause -- cannot show that altering the cause will alter the
effect
Advantages of Case-Control Studies - ANSWER- - good for screening for potential risk
factors -- can look at multiple at once, suggest new hypothesis
- helpful for rare diseases
- inexpensive, easy, fast
Cross-Sectional Studies, Surveys (Prevalence) - ANSWER- - analyze data collected on a
group of subjects at one time rather than over a period of time
- designed to determine "what is happening?" right now
Prevalence - ANSWER- proportion of people who have a given disease or condition at a
specified point in time
Blind Studies - ANSWER- - experimental study in which subjects do not know the
treatment they are receiving
- investigators may also be blind to the treatment subjects they are receiving
