Intention to treat analysis
Intention to treat (ITT) analysis means all patients who were enrolled and randomly allocated to treatment are included in the analysis and are analysed in the groups to which they were randomized
Category Clinical Research
Meta-analysis and Systematic Review
Meta-analysis is a tool for quantitative systematic review of observational studies and controlled trials that weights available evidence based on the numbers of patients included, the effect size, and often statistical tests of agreement with other trials
Measures of Variability
Measures if variability describe the average dispersion of data around a mean; most common = range, standard deviation and the standard error of the mean
Phases of Clinical Research
Phases of clinical research are the steps taken to gather evidence to determine whether a novel intervention or treatment is safe and effective for clinical use
Propensity Score Analysis
Propensity analysis refers to statistical methods used to control for treatment selection bias in observational studies
How to analyse a clinical trial
Clinicians must be able to critically appraise clinical trials to determine their internal validity. Trials should adhere to the CONSORT statement (CONsolidated Standards of Reporting Trials)
Fragility Index
OVERVIEW The Fragility Index is the minimum number of patients whose status would have to change from a nonevent to an event that is required to turn a statistically significant result to a non-significant result The smaller the Fragility Index,…
Confounding and Confounders
Confounding involves error in the interpretation of what may be an accurate measurement by attributing it to the wrong cause. A confounder is a factor that is prognostically linked to the outcome of interest and is unevenly distributed between the study groups
Incidence and prevalence
Incidence = number of individuals who develop a disease in a given period of time. Prevalence = the current number of cases in a given population
Measures of Central Tendency
Measures of Central Tendency; these indices allow a sample or population to be summarised using a single value.
Odds ratio
An odds ratio (OR) is a measure of association between an exposure and an outcome. The OR represents the odds that an outcome will occur given a particular exposure, compared to the odds of the outcome occurring in the absence of that exposure.
Power and Sample Size
It is unethical and a waste of time and resources to embark on a study when there is a high chance of a false negative result (Type II error). The commonest cause of this is having a sample size that is too small