Don’t Let Your Likert Scales Grow up to be Visual Analog Scales: Understanding the Relationship between Number of Response Categories and Measurement Error

We investigated the optimal number of response categories for Likert and Visual Analog Scales (VAS) using simulations. Reliability plateaus after 4–10 categories; however, when measurement error increases with more response options, reliability declines, and converting Likert items to VAS can drastically decrease reliability.