CITI Research Study Design Practice Test 2026 - Free Practice Questions and Study Guide

A Type I error occurs when researchers incorrectly reject the null hypothesis when it is actually true. This means that they find statistically significant results when in reality, there is no actual effect or difference present – it is simply a result of random chance. This can mislead researchers into believing they have discovered an effect when, in fact, their findings are not reliable.

This concept is crucial in statistical hypothesis testing, where the probability of making a Type I error is denoted by the significance level (commonly set at 0.05). Understanding the implications of Type I errors is essential for maintaining the integrity of research findings and ensuring that conclusions drawn are genuinely reflective of reality.