Key Concepts in Randomized Trials

Flashcards focusing on key terms and concepts related to randomized trials in clinical research.

Randomized Trials

Study designs considered the gold standard for evaluating preventive and therapeutic interventions.

Purpose of Randomization

To eliminate bias in treatment assignment and ensure comparability between treatment groups.

Masking (Blinding)

A method used to prevent participants and/or investigators from knowing which treatment participants receive.

Efficacy

The ability of an intervention to produce the desired outcome under controlled circumstances, such as in randomized trials.

Effectiveness

The degree to which an intervention works in real-world settings.

Intention to Treat Analysis

A strategy for analyzing randomized trial data by including all participants as randomized, regardless of whether they completed the assigned intervention.

Stratified Randomization

A method of randomizing participants within subgroups to ensure comparability across key characteristics.

Type I Error (α)

The probability of concluding that there is a difference when there is none.

Type II Error (β)

The probability of concluding that there is no difference when there is a difference.

Power of a Study

The probability of correctly rejecting the null hypothesis when it is false; calculated as 1 - β.

Noncompliance

When participants do not adhere to the assigned treatment in a randomized trial.

Number Needed to Treat (NNT)

The number of patients who need to be treated to prevent one adverse outcome.

Publication Bias

The tendency for journals to publish positive results more than negative or inconclusive results.

Phase I Trials

Early trials focusing on safety and dosage in a small number of participants.

Phase II Trials

Trials designed to evaluate the efficacy and safety of a new drug in a larger group of patients.

Phase III Trials

Large-scale studies comparing a new treatment against a placebo or existing treatments to confirm efficacy.

Postmarketing Surveillance (Phase IV)

Monitoring of a drug after it has been approved for use to identify long-term effects.

Comparative Effectiveness Research (CER)

Research comparing existing interventions to determine which works best under specific circumstances.

Crossover Design

A study design where participants switch from one treatment to another, allowing each participant to serve as their own control.

Factorial Design

A design that allows simultaneous testing of multiple interventions and their interactions.

Generalizability (External Validity)

The extent to which the findings from a study can be applied to settings and populations outside the study.

Internal Validity

The degree to which the results of a study accurately reflect the true relationship between treatment and outcome within the study population.