Modules 1 and 2 Flashcards
Lectures 1 & 2, book chapters 1-3, Rothman Module 2
What are the characteristics of an effective surveillance system?
Simplicity, flexibility, data quality, acceptability, sensitivity, positive predictive value, representativeness, timeliness, stability
What are the differences between public health and clinical medicine?
Public health focuses on the population at large
It is interested in prevention and aligns with epidemiology, environmental science, biostatistics, social science, etc. and uses a systematic approach
Medicine focuses on the individual and curing individual conditions
It aligns with biological sciences & pathology and uses nonsystematic approaches
What is epidemiology?
Epi (on or upon) Demos (the common people) Logy (study)
The study of that which falls upon the common people
The study of the distribution and determinants of disease frequency in human populations and the application of this study to control health problems (Aschengrau)
What is an epidemiologist?
A professional who strives to study and control the factors that influence the occurrence of disease or health-related conditions and events in specified populations and societies, has an experience in population thinking and epidemiologic methods, and is knowledgeable about public health and causal inference in health
What areas should epidemiologists have knowledge of?
Public health, clinical medicine (numerators), pathophysiology, biostatistics (denominators, testing hypotheses), social sciences
What are the objectives of epidemiology?
Identify etiology or cause of a disease
Determine extent of disease in a community
Study natural history and prognosis of disease
Evaluate preventative and therapeutic measures and modes of healthcare delivery
Provide foundation for policy development
What is a population?
Group of people with a common characteristic
What is disease frequency?
Quantifying how often disease arises in a population
Involves: developing disease definition, instituting mechanism for counting cases of disease within a specific population, and determining the size of a population
What are disease determinants?
factors that bring about change in a person’s health (demographics, environmental, social)
What is disease distribution?
analysis of disease patterns according to characteristics of person, place, and time
How is disease control achieved?
Through research and surveillance
What is the principal goal of epidemiology?
to produce information that will prove useful in improving health on a population level
What are the 3 major components of applying epidemiology?
Design (analytic, descriptive, exploratory), methods (sampling, data collection, data analysis), and methodology (quantitative versus qualitative).
How have the goals of epidemiology changed over the years?
19th century: focus on infectious disease
20th century: high income countries shifted towards non-communicable diseases
Mid 20th Century (1970s): methods formalized
Late 20th Century: formalized central disciplinary principles (180s)
What graphic format is typically used to measure time?
Y axis for frequency
X axis for time
What is public health?
A multidisciplinary field whose goal is to promote the health of the population through organized community efforts
Key activities: assessing health status of the population and diagnosing its problems, searching for causes of problems and designing solutions for them
What is secular change (Temporal variation)?
Changes which occur slowly over long periods of time (over a year)
What are point epidemics?
short term changes over limited time frames; used for short term exposures or diseases with short incubations and/or illness durations
What is seasonal variation?
a method that can be used to suggest possible etiology
What is time clustering?
Data that can be used to trace the “beginning” / intro of a specific causal agent
E.g. thalidomide causing birth defects (linked back to sleeping pill used for morning sickness)
What are epidemiological variations relating to place?
International
Variation within countries (urban-rural, local)
Building maps
What is prognosis?
Predicting the progress or outcome of the disease (expressed in terms of deaths or survivors from the disease)
What measures are used to quantify prognosis?
Cased based numbers; the denominator is the number of people with the specific disease
What are common measures of expressing prognosis?
Case Fatality Rate (CFR)
Five year survival rate
Observed survival rate
Median survival time
Relative survival rate
What is the Case Fatality Rate (CFR) specifically?
Numbers of individuals dying during a specific period of time after disease onset or diagnosis / number of individuals with specified disease
It does not include any explicit statement of time, and so is best used for short term / acute conditions
How does CFR differ from mortality?
Mortality rates include anyone at risk of dying from a disease in the denominator - both those with a disease and those who do not (yet) have a disease
What is a study design?
the program that directs the researcher along the path of systematically collecting, analyzing, and interpreting data