Statistics Flashcards
1
Q
case-control study
A
- observational study
- investigates the cause of a disease when comparing people with and without that disease
- starts with a disease of interest and selects patients with that disease for study
- then selects group without the disease to compare
- often sample sizes of the two groups are similar
- cases and controls are then compared to discover possible causal factors
- retrospective study
2
Q
cohort study
A
- an observational study that aims to investigate causes of a disease
- longitudinal, starting with an unselected group of subjects who are then followed up for a set period of time
- usually prospective, where risk factor data is collected before the person gets the disease
- aims to discover if there are particular aetiological factors causing a disease in the future
3
Q
cross-sectional study
A
- observational study
- a sample group is chosen and data from an individual is collected at one point in time only
- surveys are observational studies
4
Q
randomised control trial
A
- experimental study
- prospective and longitudinal
- assess efficacy of treatment or intervention
- compares outcomes in a group of patients treated with a new therapy, and those in a comparable group of patients with a control therapy; placebo
- patients in both groups randomised, enrolled, treated and followed over same time period
- gold standard study design; tests between two variables allowing for direct comparison of two groups, and controlling for confounding factors through randomisation. this test also reduces bias as it can be blinded
5
Q
absolute risk
A
.
6
Q
relative risk
A
.
7
Q
absolute risk reduction
A
.
8
Q
relative risk reduction
A
.
9
Q
number needed to treat
A
.
10
Q
number needed to harm
A
.
11
Q
sensitivity
A
.
12
Q
specificity
A
.
13
Q
positive predictive value
A
.
14
Q
negative predictive value
A
.
15
Q
p-value
A
.
