Randomisation
Randomisation is the process of assigning clinical trial participants to treatment groups such that each participation has a known (usually equal) chance of being assigned to any of the groups
Category Clinical Research
Early Stopping of Trials
Reviewed and revised 26 August 2015 OVERVIEW Clinical trials are planned to stop when one of the following is reached sample size event count length of follow up goal scheduled date of closure Unplanned early stopping of trials may occur…
Case-Control Studies
Case-Control Studies: a type of retrospective observational study; control patients are ‘matched’ using some criteria (age, gender), typically should have no history of the disease of interest and should be representative of the general population
Risk and Numbers Needed to Treat
Risk is a nebulous term in evidence-based medicine, as it may refer to either relative or absolute risks. Overall, absolute risks are more meaningful and can be converted in 'numbers need to treat' (NNT), which are useful in the clinical setting
Receiver Operating Characteristic Curve
Receiver Operating Characteristic (ROC) curves plot sensitivity versus false positive rate for several values of a diagnostic test
Adaptive Trial Designs
An adaptive clinical trial involves a study design in which key characteristics are adjusted while enrollment in the trial is ongoing using prospectively defined decision rules and in response to information arising from the data accumulating in the trial
Blinding and Allocation Concealment
Blinding and allocation concealment are used in Randomised control trials (RCTs) to reduce systematic bias
Chi-square Test
Chi-square Test is used to compare categorical data; often displayed in contingency table with rows (x) and columns (y)
How to conduct a clinical trial
Broad overview of the complicated process of conducting a clinical trial. Conducting a clinical trial can be conceptualised as having 14 key steps
Subgroup Analysis
Subgroup analysis involves assessing an association between an intervention (or other factor) and a subset of the patients that were exposed. Subgroup analysis can be decided upon a priori or performed post hoc
Before-and-after studies
Non-experimental observational study design used to assess the effect of an intervention based on comparison of outcomes prior to its use and afterward
Types of Research Studies
Types of study design arranged by level of evidence, from low to high