statistics in public health Flashcards
National Center for Health Statistics
part of the CDC
Federal Agency
states report to NCHS
surveys health, lifestyle, etc
Birth Certificate
Issued by local gov’t
reported to state & NCHS
has family and medical information
Death Certificates
Cause of death
Marriages & Divorces
yes
Infant
Deaths before their 1st birthday
Spontaneous fetal deaths & abortions
Census
Measures the population
happens every 10 years
geographic distribution
collects information on sex, age, race
helps track trends in immigration
completed by the US Census Bureau
Age adjusted mortality rates
Age-adjusted mortality rate is a statistical measure that is used to compare the mortality rates between two populations or across different time periods, while accounting for the differences in the age distribution of those populations.
Age specific mortality rate
Age-specific mortality rate is a measure that reflects the number of deaths in a particular age group of a population, usually expressed as the number of deaths per 1,000 or 100,000 people in that age group.
Infant mortality rate
The infant mortality rate is a measure of the number of deaths of infants under one year of age per 1,000 live births in a given population in a specific time period.
Life expectancy
Life expectancy is the average number of years that a person can expect to live, based on current mortality rates and other demographic factors such as sex, race, and socioeconomic status
Years Potential Life Lost
is a measure that estimates the number of years of potential life lost when a person dies prematurely before reaching the age of 75.
National Health Interview Survey
involves 50,000 households and provides information on a range of health topics.
National Health and Nutrition Examination Survey (NHANES)
The National Health and Nutrition Examination Survey (NHANES) involves 15 counties and 5,000 people and provides a comprehensive health assessment.
The Behavioral Risk Factor Survey (BRFS)
conducted by states and territories, reported to the Centers for Disease Control and Prevention (CDC). It is an ongoing surveillance system that collects information on risk factors and preventive health practices related to the leading causes of death and disability in the United States.
What is this data being used for?
Detect health issues
develop public health policy
plan the allocation of resources to address the need of the community
evaluate how efficient the public health interventions have been
Confidentiality
removal of identifying information: names, etc
only having restricted access to databases
& the IRB Institutional Review Board. reviews all requests for access to data by researchers
Uncertainty & Probability
These studies measure probability
p < 0.05 is not significant
P = or < 0.05 is significant
confidence intervals
margins of error
+ or - 3
small confidence interval
low likelihood of random error
Statistical Power
refers to the probability of detecting a true effect or relationship between variables, given that it exists in the population.
A study with high statistical power has a greater chance of detecting a true effect or relationship, whereas a study with low statistical power is more likely to miss a true effect or relationship
false positive
False positives can occur due to various factors such as small sample size, flaws in the study design or data analysis, or by chance.
false negatives
false negatives can occur when the sample size is too small, or the test used is not sensitive enough to detect the effect or relationship being studied.
Screening tests
May yield false positives or negatives
Sensitive screening tests
few false negatives
specific screening tests
few false positives
Population screening tests
Want to avoid missing any positives
Sacrifice specificity for sensitivity
Follow-up with more specific test
High number of false positives may render test ineffective or too costly
COVID screening
both virus and antibodies
testing exposure by testing for antibodies
FDA had pressure to get the kits out there
begs the question if these kits are 100% accurate or effective
Rapid Tests: Abbot Test
screens for virus
NYU Study
says that there are false negatives in 1/3-1/2 of cases but Abbott disputes this but this study is supported by Stanford and Cleveland clinic
having a rate like this: 50,000 will test negative if positive out of 1million people
big #
analytical sensitivity
refers to the ability of a test to detect even very low concentrations of a particular substance
clinical test performance
refers to the accuracy and reliability of a medical test in diagnosing or detecting a particular disease or condition.
clinical sensitivity
Clinical sensitivity measures the percentage of positive test results among patients with confirmed disease. This requires an independent confirmation of the disease by symptoms or another test
Challenges with COVID
tests must be highly sensitive
able to detect the disease even in asymptomatic patients
FDA must ensure sensitivity and specificity before sending tests to market
cost-benefit analysis
The estimated cost of implementing a policy or healthcare intervention should be weighed against the estimated benefits it would provide.
For example, the cost of implementing an immunization program should be compared to the cost of treating the disease that the immunization aims to prevent.
