Public health deck 2 Flashcards
Name 3 types of study design:
- Ecological
- Cross-sectional
- Case-control
- Cohort
- RCT
How is an ecological study carried out?
Routinely collected population level data to show trends and generate hypotheses
What type of study looks at the population at a point in time?
Cross-sectional or prevalence study
What type of retrospective study compares people with a disease to those without a disease for age, sex, habits, class etc?
Case-control study
What type of study follows a population over time to see if they’re exposed to agent in question and if they develop a disease?
Cohort or incidence study: prospective
What is a RCT?
Population is randomized to either interventional or control group: blind or double-blind trials.
What type of study is also known as an incidence study?
Cohort study - follows population over time to see if they’re exposed to the agent in question and develop the disease
What type of study is known as a prevalence study?
Cross-sectional study - looks at population at a point in time
Define primary prevention:
Preventing disease/condition occurring in the first place
What prevention method are immunisations?
Primary prevention
Define secondary prevention:
Detecting a disease as soon as possible to alter its course and improve health outcomes
Give an example of secondary prevention?
Screening e.g. cervical smear, breast screening programmes
Define tertiary prevention:
Slowing down disease progression whilst avoiding complications and helping people to manage their disease effectively to reduce mortality
Give an example of tertiary prevention:
Diabetes management e.g. diet advice, exercise programmes, self-monitoring.
Give an example of a population approach to prevention:
Dietary salt reduction (preventative measures delivered on population level)
What is high risk approach to prevention?
Identify individuals above a chosen cut-off and treat them (e.g. treat those with high cholesterol to avoid heart disease)
Prevention paradox?
Preventative measure that brings much benefit to the population will offer little to each participating individual.
Define screening:
Identifying seemingly health individuals at risk of disease
4 different types of screening:
- Population based
- Opportunistic
- Screen for communicable disease
- Pre-employment and occupational
Wilson and Jungar criteria for screening (x10):
- Condition screened for must be IMPORTANT HEALTH PROBLEM
- Understanding of NATURAL HISTORY of disease
- Detectable at an EARLY STAGE
- Treatment should be AVAILABLE
- FACILITIES for diagnosis and treatment need to be available
- SUITABLE TEST available
- Test suitable for POPULATION
- AGREED POLICY on who to treat
- COST balanced against benefits
- Screening is a CONTINUOUS PROCESS
Define sensitivity:
Proportion of people WITH the disease correctly identified
Define specificity:
Proportion of people WITHOUT disease correctly identified and excluded from screening test
Define positive predictive value (PPV):
Proportion of people with a positive test result who actually have the disease
Define negative predictive value:
Proportion of people with a negative test result who do not have the disease
