Stats Etc Flashcards
What is the case K-series
Report on series of patients with an outcome of interest.
No control group
Cohort study
Identification of two groups
One received the exposure
One did not
Follow-up cohorts for outcome
What is the confidence interval a measure of
Quantifies the uncertainty in measurement.
Reported as 95% = range of values within which we can be 95% sure that the true value for the whole population lies
What is crossover design study
Administration of two or more experimental therapies one after the other in a specified or random order to the same group of patients
what is a cross-sectional study
Okay sedation of a defined population at a single point of time.
Exposure and Outcome determined simultaneously
What are the control event rate (CER) and experimental event rate (EER)
Proportion of patients in the group in whim the event is observed
E.g. 27/100 = 0.27
What is incidence
The proportion of new cases of the target disorder in the population at risk during a specified time interval
What is intention-to-treat analysis
Analysis for RCT where all patients randomly assigned to one treatment or analyse together regardless of whether they completed all receive the treatment
Preserves randomisation
What is the likelihood ratio
Likelihood that a given test result would be expected in a patient with the target disorder compare to the likelihood of the same result in a patient without the target disorder
What is a meta-analysis
Systematic review using quantitative methods to synthesise and summarise results
What is negative predictive value
Proportion of people with a negative test you are free from the target disorder
What is number needed to treat
Inverse of the absolute risk reduction
Number of patients needed to treat to prevent one bad outcome
What does odds mean
Ratio of people incurring outcome compare to a number of people who don’t
What is an odds ratio
Ratio of the odds of people having a target to sort it in the experimental group relatives the odds of having the target disorder in the control group
What is positive predictive value
Proportion of people with a positive test result who have the target disorder
What is posttest odds
Odds the patient has target disorder after test completed
Pre-test odds x likelihood ratio
What is prevalence
Proportion of people with The target disorder in population at risk at a specific time
What is risk ratio
Ratio of the risk of the outcome event in the treated group to the risk of the event in the control group
RR = EER/CER
What is sensitivity
Proportion of people with target disorder who have a positive test result
What is specificity
Proportion of people without the target disorder who have a negative test result
What is relative risk reduction
Proportional reduction in rates of the bad outcome between experimental and control groups
(EER-CER)/CER
What is absolute risk reduction
Absolute arithmetic difference in rates of bad outcome between experimental and control groups
(EER-CER)
Equation for number needed to treat
1/ARR
What is the case control study
Study involves identifying patients with the outcome of interest and control patients without the same outcome.
Look back to see if they had exposure of interest
