Week 4 Flashcards
Difference between screening and diagnostics?
- Diagnostics = use of tests to ascertain if indiv WITH a symptom has the condition
- Screening = testing for indiv who do NOT have symptoms (ex: routine colonoscopy)
Surveillance =
constant watching or monitoring of disesases to assess patterns and quickly identify events that do not fin in the pattern. (who is getting the disease and where?)
What might a spike incidence (detected through surveillance) indicate?
beg of epidemic
How might surveillance techniques be applied to individuals with infectious diseases? Genetically based?
o For infectious disease, this may include monitoring of individuals who already have the disease + their contacts, as well as general pop
o If genetically based, may track through extended family relationships
What is association?
• = reasonable evidence that a connection exists between a stress or environmental factor + disease.
o May be first noticed through observation, them CHN or epidemiologist examine the data to see if the relationship is weak or strong. If strong, do more extensive examination.
What is a causal relationship?
• = when a relationship or association has been confirmed beyond doubt. There is a definitie, statistical, cause-and-effect relationship
T/F It was harder to find causal relationships when most diseases were infectious
F - is harder now with chronic disease as are multifactorial
What is necessary + what is sufficient r/t causation:
o If cause is “necessary” = that stressor must be present before given effect can occur
o If case is “sufficient” = the amount of exposure required to result in the disease (*this sounds a little different than research class?)
What is a web of causation?
diagram illustrating how various relationships among the many causes or influences intersect in a particular health outcomes
What are the criteria for causation? (7)
1) Temporal relationship = person does not get the disease until after exposure
2) Strength of assoc – exposure to specific stress or cause is most likely to bring about the disease
3) Dose-response: person who are most exposed get the most ill
4) Specificity: cause is linked to a specific disease (one bacteria leads to the specified disease)
5) Consistency: everyone who eats the contaminated food gets ill
6) Biologic plausibility: consistent with biologic/medical knowledge that is known
7) Experimental replication – several studies show same results
Two measures of morbidity?
incidence or prevalence
Why are morbidity rates important?
give a picture of the pop and a disease or health challenge over time, suggesting questions about the susceptibility of the pop + the effectiveness of either HP or treatment strategies
Prevalence =
• number of people in a w disease in given pop at a point in time / # of total pop in that same time
If a diseae is short-lived, is prevalence very useful?
When might it be useful in thsi regard?
• If disease is short lived, prev doesn’t reveal much, but may use this in epidemic situations to plan for exta staff (ex: H1N1)
How does the inc + prev compare if the disease is short lived and results in few deaths
the incidence and prev are very similar
• If chronic + long term, the incidence rate _____, while the prev _____
stays fairly static, while the prev rises
When calculating incidence, what is used as the denominator?
• When calculating incidence, it is the population AT RISK as the denominator (not going to include females when looking at incidence for prostate CA)
What is relative risk?
• divides the incidence of a given problems in a pop exposed to a given risk factor by the incidence of the same problem in a pop not exposed to that risk
How to interpret relative risk?
o If close to 1.0, both groups have same risk + risk factor in question likely not the cause
• If >1.0, risk factor in questions is at lest one significant risk facrors for the problem
• If <1.0, not a significant risk factor and may have protective qualities
Point prevalence?
• = describes the situation only for that particular point in time (do you currently smoke?)
Period prevalence vs cumulative/lifetime incidence - what questions would each of these ask in r/t smoking?
Period prevalence = have you smoked in the last 6 months?
• Cumulative or lifetime incidence statistics = have you ever smoked?
What is a main source of epidemiological data?
• Government is one of largest sources (Public Health Agency, Health Canada, Stats Canada, provincial gov ministries)
Also, Required birth and death stats
What are reportable disease?
= disease that are required to be reported by law (ex: TB, STIs, AIDS)
• PHAC developed a population health template with 8 key elements. What are they? (this is from p 256, which is not in the req’d readings but this page is on her list)
1) Focus on health of populations
2) Address the determinates of health and their interactions
3) Base decisions on evidence
4) Increase upstream investments
5) Apply multiple strategies
6) Collaborate across sectors + levels
7) Employ mechanisms for public involvement
8) Demonstrate accountability
Are also international indicators that measure quantifiable info on the health of the pop and the healthcare system. What are they? (p. 256)
: 1) health status, 2) non-medical determinants of health, 3) health system performance, 4) community and health system characteristics, 5) Equity
How and why do CHNs work with risk assessments?
- Impossible for CHNs to work with every member in the community so assess risk of whole population and provide services in accordance with that
- When doing risk assessment, CHNs ID and target clients who are most likely to contract a particular disease + assess attributes that affect or potentially affect their health
Define risk
probability that healthy persons exposed to a specific factor with acquire a specific disease
Are mortality rates usually easily accessible? Why?
• HCPs are legally required to complete death certificates for all deaths + file with government – so usually complete and easily obtainable
What is a crude mortality rate? How to calculate?
• compare number of deaths from a specific cause within the entire population (ex: totally MVAs in entire population)
o = total deaths from any cause in a given year in a population / ave total pop of the same year
What is a specific mortality rate? How to calculate?
• compare # of deaths from a specific cause in a particular subgroup (MVA deaths of teenage boys, compared with number of male teens driving at that time)
o = total deaths from a specific cause in a given year in a population (subgroup) / average number of pop (subgroup) for the same year
Proportional mortality
• can be sued to stratify crude mortality rates. The number of deaths from a specific cause in a given pop for a particular time period is compared with total number of deaths in that same pop in time period (state x% of deaths in a given year were due to _____)
What kind of mortality rates are often used to gauge health of population
Maternal + infant mortality rates
Maternal deaths =
Perinatal deaths =
o Maternal deaths = any deaths of the mother resulting from preg-related causes
o Perinatal death rate = fetal deaths occurring during the last few months of preg or during the first 7 dys of life
Neonatal deaths =
Infant death rates =
o Neonatal death rates = death of infant in first 28 days of life
o Infant death rates = death in first year of life
What is an odd’s ratio?
- OR describes the likelihood of a participant in in the experimental group having an event (ex: preg), divided by the by likelihood of a participant in the control group having the event
- = exposed persons with the disease/unexposed persons with the disease DIVIDED BY exposed persons without the disease/unexposed persons without the disease
- Is a summary statistic, like relative risk
- Provides epidemiologists with an estimate of the relative risk facor
See page 213 on how to calculate OR
…
What is a “target population”
refers to the pop for whom a nursing intervention is intended (p. 251)
