Clinical Investigation Exam 2

0.0(0)
studied byStudied by 0 people
GameKnowt Play
learnLearn
examPractice Test
spaced repetitionSpaced Repetition
heart puzzleMatch
flashcardsFlashcards
Card Sorting

1/38

encourage image

There's no tags or description

Looks like no tags are added yet.

Study Analytics
Name
Mastery
Learn
Test
Matching
Spaced

No study sessions yet.

39 Terms

1
New cards

These studies compare subjects who have the condition (case) with patients who do not have the condition (controls)

Case control studies

2
New cards

Case control studies are often used for…

studying rare diseases or outcomes and long latency periods (cancer)

3
New cards

The purpose of case control studies are…

to determine whether an exposure is associated with an outcome (disease of condition)

4
New cards

These are advantages of which type of study?

efficient for rare diseases

quick and inexpensive (compared to others)

study multiple exposures or risk factors

requires fewer subjects

Case-controls study

5
New cards

There are challenges for which type of study?

recall bias - participants may not remember past exposures accurately

selection bias - poorly choses controls can skew results

cannot establish causation - only associations

temporal ambiguity - difficult to be certain exposure preceded disease

Case-control study

6
New cards

What type of case control study is:

Each case is paired with one or more controls based on specific characteristics (age, sex)

Matched case control study

7
New cards

Which type of case-control study is:

Conducted within a defined cohort, cases and matched controls are selected from the same cohort

Nested Case control study

8
New cards

Which type of case control study is:

A variation where controls are randomly selected from the cohort, not matched

Case-cohort study

9
New cards

What are best practices for case-control studies?

Clear case definitions

appropriate controls

blind interviewers or standardized data collection tools

matching and statistical adjustment

10
New cards

These studies are observational and longitudinal that follows a group over time to examine the association between exposures and outcomes

Cohort studies

11
New cards

What is the purpose of cohort studies?

to determine whether an exposure is associated with the risk of developing a particular outcome

helps establish relationship between exposure and outcome

12
New cards

This type of cohort study:

starts before any outcomes occur and move forward in time

participants are followed to observe outcomes

Prospective cohort study

13
New cards

This type of cohort study:

both exposure and outcome have already occurred at the start of the study

investigators look back in time in records or databases to classify exposure and outcomes

Retrospective cohort study

14
New cards

Using medical records from the past 20 years to compare disease rates in people exposed vs unexposed to a chemical. Is an example of what type of study?

Retrospective cohort study

15
New cards

Following smokers and nonsmokers for 10 years to see who develops lung cancer. Is an example of what type of study?

Prospective Cohort Study

16
New cards

What is the odds ratio?

What do the following represent?

>1

< 1

= 1

odds ratio estimates the association between exposure and outcome

> 1: exposure might be a risk factor

< 1: exposure might be protective

= 1: no association

17
New cards

What is the relative risk ratio/incidence rate ratio?

What do the following represent?

>1

<1

=1

compares the risk of developing the outcome in exposed vs unexposed individuals

>1: may increase risk

<1: may be protective

=1: no association

18
New cards

There are advantages of what type of study?

establish temporal relationships

incidence and relative risk calculations

study multiple outcomes from a single exposure

less recall bias

Cohort study design

19
New cards

These are challenges of which study design?

time consuming

expensive

loss to follow-up (attrition bias)

not efficient for rare diseases

may involve confounding variables if not properly controlled

Cohort study design

20
New cards

What type of cohort study is a fixed group, no new participants added

closed cohort study

21
New cards

What type of cohort study has participants that can enter or leave over time

open cohort studies

22
New cards

what type of cohort study is a case controlled study conducted within a cohort, an efficient way to analyze expensive or rare exposures

nested case control study

23
New cards

What are best practices for cohort studies?

well-defined inclusion/exclusion criteria

accurate exposure measurment at baseline

minimize attrition bias

control confounding variables - via stratification, regression, or matching

ensure sufficient follow-up time to capture outcomes

24
New cards

What are some major differences between cohort and case-control studies?

Time direction, outcome status at start, best for, measures, cost/time, temporality

Time

  • Cohort - prospective or retrospective

  • Case-control - retrospective

Outcome

  • cohort - outcome free

  • case control - cases already have outcome

Best for

  • cohort - rare exposures, common outcomes

  • case control - rare outcomes, long latency

Cost

  • cohort - higher

  • case control - lower

Temporality

  • cohort - strong

  • case control - weak

25
New cards

these aim to summarize the best available evidence

Systematic review

26
New cards

true or false.

all meta-analyses should be based on systematic reviews, but not all systematic reviews include a meta analysis

true

27
New cards

this is a quantitative technique that combines the statistical results of multiple studies. ex. an overall risk ration, odds ratio, or mean difference

Meta-analysis

28
New cards

what is the fixed effect model?

assumes one true effect size, used when studies are very similar

29
New cards

what is a random effects model

assumes effect sizes vary across studies, accounts for heterogeneity

30
New cards

These are advantages of what?

reduces bias through transparent methodology

provides a comprehensive summary of evidence

systematic review

31
New cards

There are advantages of what?

increases statistical power

provides precise estimates of effect

can identify subtle effects missed in individual studies

Meta-analysis

32
New cards

What is the equation for prevalence

number of existing cases / total population at time

33
New cards

What is the equation for incidence

#new cases / (total population - those with the disease)

34
New cards

What is the EER equation?

Number of events in experimental group / total number in experimental group

35
New cards

What is the equation for CER?

number of events in control group / total number in control group

36
New cards

What is the equation for absolute risk reduction?

CER - EER

37
New cards

What is the equation for relative risk?

EER/CER

38
New cards

What is the equation for Relative risk reduction?

(CER - EER) / CER

39
New cards

What is the number needed to treat equation?

1/(CER-EER)