Measuring Risk Flashcards
The risk of breast and prostate cancer, heart disease and stroke, Alzheimer disease, autism, and osteoporosis are examples of topics in which the public has developed a strong
Interest
Characteristics associated with an increased risk of disease are called
-Some are inherited, some are part of the physical environment, some are part of the social environment
Risk factors
Some of the most powerful risk factors are
Behavioral (i.e. smoking, unprotected sex, etc.)
The affordable care act mandates that insurance now covers
Preventative services (i.e. screening tests, “routine visits”)
Means that a person, before becoming ill, has come in contact with or has manifested the factor in question
-can take place at a single point in time or over a period of time (i.e. cigarette smoking)
Risk factor exposure
Cigarette smoking, hypertension, sexual promiscuity, and sun exposure are examples of risk factors that have the risk of disease being more likely to occur with
Prolonged exposure
A genetic/familial risk factor could be the susceptibility to sickness and
Disease genes
Drug or chemical exposures in the home, community, or workplace environment are
Environmental risk factors
Radioactivity, Noise, and vibration are all
Physical agents of risk
What are two biological agents?
Infectious agents (bacteria, viruses, etc.) and allergens
Blood born pathogens, MRSA, and multiple drug resistant tuberculosis are examples of
Infectious agents
Stress, Life-threatening trauma, PTSD, and depression are all
Psychosocial agents
Repetitive motion jobs or hobbies, heavy lifting, and blast injuries (explosions) are all examples of
Mechanical agents
What are four life-style risk factors?
- ) Controlled substances
- ) Uncontrolled substances (i.e. alcohol, cigarettes)
- ) Unsafe sex
- ) Excessive sun exposure
Most morbidity or mortality is caused by chronic diseases, for which it is nearly impossible for a physician to use their own experiences to recognize the
Risk factors
The time between exposure and event
Latency
What causes SARS?
Coronavirus
Factors related to education, such as poor nutrition, less prenatal care, and cigarette smoking are remote causes of
Low birth weight
It is now clear that about half of lifetime users of tobacco will die because of
Tobacco use
Even though we have certain “common” diseases, the incidence of disease is actually
Low
The most common cause of cancer deaths in the US and people who smoke are as much as 20 times more likely to develop t than those who do not smoke
Lung cancer
Even still, the yearly incidence of lung cancer in people who have smoked heavily for 30 years is
2 to 3 per 1,000
The effects of individual risk factors for chronic disease are
Small
Just because risk factors predict disease, it does not necessarily mean that they actually cause the disease, meaning the risk factor may be
Confounded to another variable
A risk factor that is not a cause of disease is called a
Marker
Removing a marker may not remove the
excess risk associated with it
People with schizophrenia have higher rates of lung cancer. Schizophrenia itself does not cause lung cancer, however, as much as 80% of population with schizophrenia smoke cigarettes. Therefore, schizophrenia could be thought of as a
Marker for lung cancer
What percentage of deaths in asbestos workers is due to asbestos exposure?
45%
Multiple risk factors can increase the overall risk, meaning multiple risk factors have a
Multiplicative effect
Statistically combining risk factors produces a risk prediction model or a risk prediction
Tool
What is a risk prediction model for predicting cardiovascular events?
Framingham Risk score
Short term hospital risk prediction tools include the
Patient At Risk of Re-admission Scores (PARR)
Prediction tools have also combined diagnostic test results, for example, diagnosing the occurrence of pulmonary embolism (Wells score) or predicting stroke risk in atrial fibrillation, which is the
CHADS score
Mapped cholera cases in London and based his inferences on the analysis of spatial patterns
John Snow
The probability of an event in a population under study. It’s value is the same as that for incidence, and the terms are often used interchangeably
Absolute Risk
The best way for individual patients and clinicians to understand how risk factors may affect their lives
Absolute risk
Asks the question, what is the incidence of disease in a group initially free of the condition?
Absolute risk
Asks the question, what is the additional risk (incidence) of disease following exposure, over and above that experienced by people who are not exposed?
Attributable risk
Asks the question, how many times more likely are exposed persons to become diseased, relative to non-exposed persons?
Relative risk (risk ratio)
The absolute risk of disease in exposed persons minus the absolute risk in non-exposed persons
Attributable risk
The additional incidence of disease related to exposure, taking into account the background incidence of disease from other causes
Attributable risk (risk difference)
The ratio of percentage of exposed persons with disease, divided by the percentage of non-exposed persons with the disease
Relative Risk (RR)
The risk of a bad outcome is increased when the RR is
Greater than 1
The risk of a bad outcome is decreased when the RR is
Less than 1
Tells us by how much the treatment reduced the risk of bad outcomes relative to the control group who did not have the treatment
Relative Risk Reduction (RRR)
Used when we are talking about exposure/disease incidence studies
Risk Difference
Used when we are talking about treatment/disease prevention studies
Risk Reduction
The most useful way of presenting research results to help your decision-making
Absolute Risk Reduction (ARR) also called risk difference
If the ARR for a treatment was 8 percent, then if you treated 100 children
8 would be prevented from bad outcomes
What is the number needed to treat (NNT)?
100% / ARR
Absolute risk makes the risks or benefits look
Smaller
Relative risk makes the risks or benefits look
Bigger
A measure of effect size
Relative risk
What is the equation for the relative risk reduction (RRR)
1-RR
You want to be very careful when dealing with
Risk reduction language
What is the most straight forward way to classify risk?
ARR (because you can also convert it to NNT)
NNT is best expressed in a
Sentence
If you are comparing two treatments, what is the Relative Risk (RR)
Rsk of treatment 1 / Risk of treatment 2
