Heath and Society Flashcards
Disadvantages of cohort studies
Expensive
attrition (i.e. people may drop out)
Must consider how long for risk factor to cause disease
Disadvantages for case control
Recall bias
Advantages of case control study
observational study
good for rare diseases
Good for tracing source of an outbreak
What should be considered when critiquing systematic reviews
Inclusion of studies:
Publication bias
Studies not in english
Define sensitivity
the likelihood that a test will pick up someone with disease
A highly specific test will…
Correctly identify a high proportion of people free from disease
Define positive predictive valve
Probability that those with a positive result truly have disease
Define negative predictive value
probability that those with a negative result truly are disease free
What is a 95% confidence value
The range in which the population mean is 95% likely to lie
What is a p value
Probability of results being found if there is no difference in treatments (accept null hypothesis)
Risk ratio
Ratio of the risk of an event between two groups
used in cohort studies
Odds ratio
chance that something will happen : compared to chance that something will not
(used in case control studies)
Define relative risk
One population’s risk compared to another population
Define absolute risk
one population’s risk in its own right
What is intention to treat analysis?
Participants in a trial are analysed within the group they were allocated, even if they didn’t complete the trial
Suggest the criteria for a suitable screening test
Simple, safe, precise and validated
Distribution of test values should be known and suitable cut-off agreed
Benefits outweigh risk of screening
There should be effective treatment with evidence of early detection leading to better outcomes
Formula for positive predictive value
Number of those who truly have disease who screened positive/all those who tested positive
Steps in the NHS complaint system
1) Raise matter verbally or written with practitioner or NHS England or local CCG
2) Parliamentary and Health service ombudsman (who is independent of the NHS and government)
Disadvantages of using mortality rate to measure hospital performance
- Most hospital deaths are not preventable
- Adjusting for risk of death is complex and only partially achieved
- Poor correlation with other measures of quality for example specialist centres treat rarer more complex cases and therefore have higher mortality rates
Who inspects for quality in the NHS?
Care quality commission
National audit office
List ways in which quality of care can be measured
CQC inspection rating A&E performance (and wait times) Mortality rate % of patients waiting less than 18 weeks friends and family rating
Three aspects of Donabedian Quality
Structure
Process
Outcome
Formula for NNT
1/(rx difference)