[1] Frequency Flashcards Preview

[IDC 212] 1st Lecture Exam > [1] Frequency > Flashcards

Flashcards in [1] Frequency Deck (19)
1

In a Fraction of Proportions, What is the Numerator and What is the Denominator?

Numerator: Cases/Outcomes of Interest

Denominator: Population Examined or at Risk

2

Define: Prevalence

Proportion of a group of people possessing a condition at a particular time/period

3

Define: Point Prevalence

Proportion of cases (both old and new) at a single point in time

4

Define: Period Prevalence

Proportion of cases (both old and new) present during the given time interval

5

Define: Incidence

Proportion of the population at risk who develop the condition during a given time period

6

[Incidence vs. Prevalence]

Numerator
Denominator
Time
Design
Purpose

Incidence:
New Cases
Population at risk at the beginning of period
Time interval
Cohort study
Causality

Prevalence:
All cases
Whole population
Single point/Period
Cross-sectional
Association; Good for Diagnostic Test

7

What is the Relationship Between Prevalence and Incidence

Prevalence = Incidence x Average Disease Duration

8

Characteristic of Diseases with Long Duration with regards to Prevalence and Incidence

High Prevalence
Low Incidence

9

Characteristic of Highly Virulent Diseases with regards to Prevalence and Incidence

High Incidence
Short Duration (Kills fast)

10

[Formula]

Average Disease Duration

Prevalence/Incidence

11

[Formula]

Case Fatality Rate

# People who died within a period / # People with disease at start of the period

12

[Formula]

Complication Rate

# People who develop complications / # People with disease at start of the period

13

[Formula]

Infant Mortality Rate

# Deaths in a year of children <1 year old / # Live births in same year

14

[Formula]

Perinatal Mortality Rate

Fetal Deaths (>28 weeks AOG) + Neonatal Deaths (<7 days) / Fetal Deaths + Live Births

15

Define: Prevalence Study

Certain population is examined for the presence of the condition of interest at a certain cross-section in time

16

In a prevalence study of TB among 160 students, with a random sample size of 60 students 12 had TB.

What is the prevalence rate?

20%

17

Differentiate: Dynamic vs. Fixed Population

Fixed: No influx/efflux of subjects

Dynamic: With influx/efflux of subjects

18

[Formula]

Incidence Density

# of New Cases / Summation of Person-Time

19

[Formula]

Cumulative Incidence

# of New Cases / Population at Risk