RCTPRES2.pptx

 Overview Common Epidemiology Study Types Definition of a RCT Prototype design of an RCT How to evaluate an RCT Summary  Descriptive vs. Analytic Descriptive Analytic Designed to describe Designed to examine the distribution of associations o...

 Overview Common Epidemiology Study Types Definition of a RCT Prototype design of an RCT How to evaluate an RCT Summary  Descriptive vs. Analytic Descriptive Analytic Designed to describe Designed to examine the distribution of associations or various characteristics without regard to causal hypothesized causal or other hypotheses. relationships. Hypothesis generating. Often used to identify or measure risk factors or No control group. the health effects of certain exposures. Has a control group. Common Epidemiologic Study Types Study Type Methodologic Strength Descriptive Weakest Case Report Case Series Cross-Sectional Analytic Observational: Case-Control Cohort Experimental: Randomized Control Trial Strongest  RCT : Definition A comparative study of the effect of two or more interventions on a given outcome, in which exposure to a particular intervention is determined by random chance. One of the interventions may be no intervention Various Names For RCTs Clinical Trial Experimental Study Controlled Trial Gold Standard Trial Intervention Trial  Situations Favoring RCTs Legitimate uncertainty about the effect of alternative interventions on the outcome (“Equipoise”) Exposure of interest is a modifiable factor over which individuals are willing to relinquish control. Treatment not already accepted Outcome of interest is reasonably common. Effects are of moderate size  Prototype Design For An RCT Source EXPERIMENTAL Population INTERVENTION OUTCOME Eligible YES NO Consent to SAMPLE RANDOMIZATION participate YES NO COMPARISON INTERVENTION RCT Components Assignment Assessment Analysis Interpretation Extrapolation  Subject Selection Selection of subjects for the study is not random. The study should have well defined inclusion and exclusion criteria. High risk individuals often necessary Exclusions should be reasonable, e.g., No expected benefit Require the treatment Inability to participate Selection may affect generalizability (external validity)  Assignment of Subjects Reference Population Nonparticipants Potential Participants Participants Exclusions (Study Population) Tx Allocation Tx Group Comparison Group