PH Flashcards
HSMRs
(No. Deaths / expected deaths) x 100
those who died within 30 days of discharge
Absolute risk
Risk of disease over time period
No events in group / No people in group
ARR
P(risk in exposed) - P(risk unexposed)
RRR
1 - RR
Relative risk
Used to compare risk of two groups
1 = +ve correlation
0 = no association
-1 = -ve correlation
PPV
Chance +ve result is correct
TP / TP + FP
NPV
Chance -ve result is correct
TN / TN + FN
Sensitivity
Test +ve when disease is present
TP / TP + FN
Specificity
Tests -ve when no disease is present
Data governance
Establishes processes that ensure quality & security of data used in an organisation
RCTs
- Design
- Recruitment ——> give info & gain consent
- Allocation
- Follow-up
- Analysis
- Reporting results—-> uses CONSORT
+ves for RCTs
Suitable for large samples
Clear, measurable impacts
-ves for RCTs
Not suitable for small samples
Hard to measure results
Takes time
NHS Health Check
40-74 y.o
Every 5 years
Diabetes
Heart disease
Kidney disease
Stroke & dementia
Attributable risk
Excessive risk accounted for by an exposure
Health promotion parts
Health education
Health protection
Disease prevention
Study designs hierarchy
RCT
Cohort
Case-control
Cross-sectional
Ecological
Case series
Case report
Cost minimisation
Cheapest option
Cost utility
Assesses benefits using QALYs
Cost effectiveness
Intervention cost compared via common outcome (e.g. years of life saved)
Cost benefit
Compared the costs and benefits
Case control
Disease status known when recruiting
retrospective
Cohort study
Recruitment is independent of disease status
- Fixed: if people leave, they are not replaced
- Dynamic: if people leave, can be replaced if eligible
Selection criteria:
- representative of pop.
- disease free at start
Confounding
Risk factor appears to be associated w/ disease but association is b/c of other unconsidered risk factors
How do you decrease the effect of confounders
Matching design
Stratification
Bowel Ca screening
FIT test
Every 2 yrs
60-74 y.o
Breast screening
Mammogram
50-71 y.o
Cervical screening
HPV test
25-64 y.o
Every 3-5 yrs
Newborn screening
72hrs
Then 6-8 weeks
Incidence
People that BECOME ill
New cases / no. at risk
Prevalence
People who ARE ill
Cases / no. in pop.
Variance
(Xi- mean)^2 / n - 1
Xi = select no.
n = no. Observations
S.D
Square root of Variance
Standard Error
S.D / sq. root of n
1, 2 and 3 S.D.
1 S.D = 68.3%
2 S.D = 95.5%
3 S.D = 99.7%
