CAT (Computer Adaptive Testing)

Definition

Computer Adaptive Testing (CAT) is the psychometric algorithm used by the NCLEX that adjusts the difficulty of each question based on the candidate's responses. The test ends when the algorithm can determine pass/fail with 95% statistical confidence.

How It Works

• Starts with a medium-difficulty item
• Correct answer → slightly harder next item
• Incorrect answer → slightly easier next item
• Test ends when ability measurement is consistently above or below the passing standard

Implications for Test-Takers

Receiving harder questions does NOT mean you are failing. It often means you are performing well. The goal is to maintain consistent accuracy on items near your ability level. The exam ranges from 85 to 150 items for the NCLEX-RN.

Stopping Rules

• 95% Confidence Interval Rule
• Maximum Items Rule (150)
• Run-Out-Of-Time (ROOT) Rule at 5 hours

NCLEX Relevance

Explains the variable length of the exam. Focus on answering each item thoughtfully rather than rushing.