Analysis & Expressing Resultd in Clinical Trials Dr. Khalili

Type of Comparisons Dr. Khalili Trials to Show Superiority Trials to Show Eqivalance or Non-inferiority Trials to Show Dose-Response Relationship (Dose Finding Trials)

 Baseline Data Analysis  Outcome Data Analysis – Continious Data – Binary Data – Survival Data Analysis of results Dr. Khalili

Baseline Data Analysis To: – Check generalizability – Check comparability of treatment groups The variables should be considered: – The characteristics of the disease (type, severity, duration, …) – Prognostic variables – Other coincidence diseases – Previous treatments Use of statistical tests! Dr. Khalili

Outcom Analysis Continious Data:  Outcome analysis  Change score analysis  Analysis of Covariance (ANCOVA) Binary Data  Absolute Risk Difference (ARD)  Number needed to Treatment (NNT)  Risk Ratio (RR) or Odds Ratio (OR)  Adjusting for baseline covariates using logistic models Dr. Khalili

Protocol Deviation Patient ineligible Wrong treatment Competing events Noncompliance Loss to follow up Missing data Dr. Khalili

Protocol Deviation Approaches for analysis:  Intention to Treat  Per Protocol Adheres only As treated Dr. Khalili

Per-protocol Analysis A ‘per-protocol’ analysis excludes all patients who are known not to have completed the trial as planned.  Drop-outs  Non-compliers  Poor compliers  Falsely included Dr. Khalili

Intention to Treat An ‘intention to treat’ analysis actually analyses patients according to the treatment the trialist intended for them. Thus, a patient assigned to the active treatment, but who confessed to not taking it, would nevertheless be analyzed as if she had received the active treatment. Sometimes this is described as, ‘if randomized then analyzed’ Dr. Khalili

Intention to Treat (ITT) To keep randomization effective To evaluate effectiveness not efficacy Considered for pragmatic RCT Should be checked with the “Best” case and “worst” case analyses Decreases the power of study Dr. Khalili

Intention To Treat Vs Per-Protocol AA ABBBBA 1&2 Vs 3&4 Intention to Treat 1 Vs 2 Adheres only 1&4 Vs 2&3 As Treated Dr. Khalili

Some issues in multiple comparisons Multiple treatments Multiple outcomes Repeated measures Interim analyses Subgroups analyses Dr. Khalili

So much difficulty in research but we can do that. Dr. Khalili