HSPH Flashcards
How do you calculate relative risk?
Incidence of disease in exposed divided by incidence of disease in unexposed
What are the three ways to adjust for confounders?
Stratify (taking a weighted av of the two relative risks), log-binomial regression, poisson regression
What do Kaplan-Meier curves plot?
The proportion of people surviving without an event over time
What is absolute excess risk?
Risk in exposed - risk in unexposed
What is formula for attributable proportion?
p(relative risk -1) divided by 1+p(relative risk -1) where p is the population of the study that smoke etc
What type of study is matching important?
Case control
When is the odds ratio a good estimate of relative risk?
If the disease is rare
When would you do parallel group vs cross over?
Parallel = when effect of treatment is not reversible
Cross-over = when effect of treatment is reversible
How do you calculate number needed to treat?
= 1/absolute difference in risk
What is the two sided Z score for 90% confidence?
1.64
What is the two sided Z score for 95% confidence?
1.96
How would you calculate the 95% reference range?
Mean +- 1.96xSD
How do you calculate standard error of the mean?
= standard deviation divided by the square root of sample size
What is Steele’s self affirmation theory?
That people are motivated to protect their sense of self integrity so when this is threatened they can act defensively or seek affirmation in other areas of life
What does NICE count as lower intellectual ability in terms of learning disability?
IQ less than 70
