Population Health Research

Question 1

define epidemiology?

Answer 1

the study of distribution or determinants in health related states or events in specified population

Question 2

what is a health related state?

Answer 2

any state of health that can happen to a population - it is an outcome

Question 3

how can you measure distribution?

Answer 3

as the frequency using count, rate or risk - descriptive epidemiology

Question 4

what is a determinant?

Answer 4

anything that can cause an outcome - chemical, biological, physical, social, behavioural, cultural - analytical epidemiology

Question 5

what is a prospective study?

Answer 5

start with a cohort with or without the exposure and follow up until disease

Question 6

what is science based on?

Answer 6

science is based on evidence and not belief - based on research which allows us to interrogate the evidence

Question 7

what is the point of testing a hypothesis?

Answer 7

to prove the weight of evidence - can never prove, only reject

Question 8

what is the process of hypothesis testing?

Answer 8

observations and then propose a hypothesis. you then test the hypothesis and reject or do not reject, modify and then retest

Question 9

what is humourism?

Answer 9

ill health that is caused by imbalances in four fundamental characteristics - temperament, climate, seasons and alchemic element

Question 10

what is EBM?

Answer 10

evidence based medicine. David Sackett in 1996 said: the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients

Question 11

what is ebm comprised of?

Answer 11

individual clinical expertise, best available external clinical evidence and patient values and expectations

Question 12

what are the five As?

Answer 12

ask, access, appraise, apply, assess

Question 13

what are probabilistic events?

Answer 13

these are events where the exposure does not necessarily lead to the outcome - it is useless to observe individual people with this - work with groups, and use probability to describe, predict and make causal inferences

Question 14

what is a census?

Answer 14

when the sample is the same as the total population, if the study population is the total population then it is a population based study

Question 15

what is a case report?

Answer 15

detailed report of the medical course of an individual patient

Question 16

what is a case series?

Answer 16

advanced case report - sample of cases with same disease - can get description, natural history and prognosis and treatment methods

Question 17

what is a register based study?

Answer 17

special type of case series. Count and collect information on people who are diagnosed and can then infer the occurrence per population

Question 18

what are the divisions of a predictive or inferential study?

Answer 18

from predictive it splits into observational or experimental.Experimental comprises pre-post studies, quasi experiments, RCTs and randomised cross over trials. Observational can be a case control, natural experiment or case-crossover study. It also has a branch for case series, register based, cross-sectional, cohort and ecological

Question 19

other than the observational descriptive studies, what is the other type of descriptive studies?

Answer 19

case reports

Question 20

what is a cross sectional study?

Answer 20

study of a group of people or population at a single point in time.

Question 21

what is a cohort study?

Answer 21

it is a study that examines groups of people over time - longitudinal on cohort with cross section at time intervals

Question 22

what is an ecological study?

Answer 22

studies of risk modifying factors on health or other outcomes on populations - these populations are defined geographically or temporally - factors and outcomes are averaged and compared

Question 23

how can hypotheses be generated?

Answer 23

individual level, temporal characteristics, or area level

Question 24

what are the benefits of ecological studies?

Answer 24

they are cheap and easy to perform with publicly available data, can make large scale comparisons and are useful for generating hypotheses

Question 25

what are the disadvantages of ecological studies?

Answer 25

cannot make causal inference, ecological fallacy if they are applied at an individual level and it is likely that you will miss some members meaning there is a potential for bias

Question 26

what are health outcomes?

Answer 26

they are individually measured outcomes combined to create population level data

Question 27

what does the hypothesis need to be?

Answer 27

valid - does the outcome measure what is intended?
responsive - can the outcome detect changes?
reliable - is the measurement consistent?

Question 28

what does a research question need to be?

Answer 28

plausible - likely link
falsifiable - can be rejected using scientific methods
directional - stating the proposed direction
precise - detailed