measuring and describing disease Flashcards
what is epidemiology?
the study of the distribution and determinants of health related states or events in specified populations and the application of this study to the control of health problems
i.e. how often diseases occur in different groups of people and why
what is an endemic disease?
resides within a population
what is an epidemic disease?
disease that befalls a population
what is primary prevention?
prevention of disease through the control of exposure to risk factors
e.g. reduce salt intake to reduce risk of hypertension
what is secondary prevention?
application of available measures to detect early departures from health to introduce appropriate treatment and intervention (i.e. early intervention)
e.g. prescribing antihypertensive drugs for a patient newly diagnosed with hypertension
what is tertiary prevention?
application of measure to reduce or eliminate long term impairments and disabilities, minimising suffering caused by existing departures from good health and to promote the patient’s adjustments to their condition (i.e. prevent impact of disease from taking hold)
e.g. rehabilitating someone who had a stroke so that they can return to pre-morbid activities
what are the features of qualitative research?
explores underlying ideas and themes to inform research questions and possible future hypothesis
expresses findings in words
relies on smaller number of participants, but has a substantial amount of detail
often used earlier in research process (starting point)
how are epidemiological findings interpreted?
association, causation, validity, bias
confounding and effect modification
what are “odds”?
ratio of probability of an event to its complement
i.e. ratio of number of people that have the disease to number of people that don’t have the disease
what is prevalence?
proportion of individuals in a population who have the disease or attribute of interest at a specific timepoint
reflects both occurrence and duration of a disease
what is the disadvantage of using prevalence?
no information on new cases of disease
not helpful if disease has short duration
how can prevalence be used?
assess health of a population
plan health services/allocate resources
monitor disease over time
what is cumulative incidence (incidence proportion/risk)?
proportion of the population with a new event during a given time period
number of new cases during period of interest over number of disease free individuals at start of time period (individuals who already had the disease when the time period started should be excluded from numerator and denominator)
what is a disadvantage of cumulative incidence?
can only be calculated if there is follow up of participants
competing risks (e.g. cancer diagnosis - if someone dies of other causes, it is unknown whether they would hypothetically have developed cancer)
what is incidence rate?
number of new cases per unit of person-time
number of new cases during follow up period over total person-time by disease free individuals
