Wondering how long you have for test day? Or how each NBEO is scored?

How Long Are the NBEO Part 1, Part 2, and Part 3 Exams? Understanding Exam Length and Scoring

One of the most common questions optometry students ask before board exams is, "How long are the NBEO exams?" Closely behind that is "How are the exams graded?"

Understanding the format, timing, and scoring of each examination can help you prepare more effectively and reduce test-day anxiety. This guide provides an overview of the current NBEO examination structure for Part 1 (Applied Basic Science), Part 2 (Patient Assessment & Management), and Part 3 (Patient Encounters and Performance Skills).

Note: The NBEO periodically updates its examination format and policies. Always verify the latest information on the official NBEO website before your exam. OD on the GO is not affiliated with NBEO. 

NBEO Part 1 (Applied Basic Science)

How Long Is the NBEO Part 1 Exam?

The NBEO Part 1 (ABS) examination is administered at Pearson VUE testing centers.

Candidates are scheduled for approximately 9 hours at the testing center, which includes:

  • Security check-in

  • Tutorial

  • Optional breaks

  • The computer-based examination

The examination itself contains 350 multiple-choice questions divided into multiple testing blocks.

Although it is a long day, the scheduled time includes more than just answering questions, so don't be surprised by the length of your appointment.

How Is NBEO Part 1 Graded?

Each question contributes to your overall examination performance.

Contrary to popular belief:

  • There is no penalty for guessing.

  • Questions are statistically analyzed after each administration to ensure fairness.

  • Your raw score is converted to a scaled score ranging from 100 to 900.

A scaled score of 300 or higher is considered passing.

Because scores are scaled, the number of questions needed to pass may vary slightly between administrations.

NBEO Part 2 (Patient Assessment & Management)

How Long Is the NBEO Part 2 Exam?

Part 2 is also administered by computer at Pearson VUE testing centers.

Candidates should plan to spend most of the day at the testing center. The examination consists of numerous clinical cases requiring diagnosis, interpretation of findings, and patient management decisions.

Questions frequently include:

  • Slit lamp photographs

  • Fundus photographs

  • OCT images

  • Visual fields

  • Laboratory data

  • Clinical history

The emphasis is on applying clinical knowledge rather than recalling isolated facts.

How Is NBEO Part 2 Graded?

Part 2 evaluates two related competencies.

Patient Assessment & Management (PAM)

This portion evaluates your ability to:

  • Interpret patient findings

  • Formulate diagnoses

  • Develop treatment plans

  • Select appropriate follow-up care

Treatment and Management of Ocular Disease (TMOD)

Candidates also receive a separate TMOD score evaluating management decisions related to ocular disease.

Like Part 1, Part 2 scores are converted to a scaled score from 100 to 900, with 300 representing the passing standard.

NBEO Part 3 (Patient Encounters and Performance Skills)

How Long Is the NBEO Part 3 Exam?

Unlike Parts 1 and 2, Part 3 is not simply a multiple-choice examination.

Candidates travel to the National Center for Clinical Testing in Optometry (NCCTO) to complete standardized patient encounters and clinical performance stations.

Throughout the examination, candidates are evaluated on their ability to:

  • Obtain an appropriate patient history

  • Communicate professionally

  • Perform clinical procedures

  • Interpret examination findings

  • Develop appropriate diagnoses

  • Recommend evidence-based management

Each station is carefully timed, requiring efficient organization and communication.

How Is NBEO Part 3 Graded?

Part 3 is scored differently than Parts 1 and 2.

Instead of receiving a numerical scaled score, candidates receive a simple:

  • Pass

  • Fail

Candidates who do not pass receive performance feedback indicating areas requiring improvement.

Examiners evaluate much more than simply arriving at the correct diagnosis. Professionalism, communication, clinical reasoning, examination technique, and patient management all contribute to overall performance.

Frequently Asked Questions

Is there a penalty for incorrect answers?

No. There is no penalty for guessing on the computer-based multiple-choice examinations, so every question should be answered.

What is a passing score?

  • Part 1: 300 (scaled score)

  • Part 2: 300 (scaled score)

  • Part 3: Pass/Fail

Does everyone need the same number of correct answers to pass?

Not necessarily.

Because NBEO uses scaled scoring and statistical equating, the exact number of correct answers required may vary slightly from one examination administration to another while maintaining the same passing standard.

Final Thoughts

Knowing the format of each NBEO examination allows you to prepare more strategically. Part 1 emphasizes mastery of foundational science, Part 2 focuses on clinical reasoning and patient management, and Part 3 evaluates your ability to apply those skills during realistic patient encounters.

No matter which examination you're preparing for, the most successful students combine active learning, repeated practice questions, and consistent review over several months rather than relying on last-minute cramming.

At OD on the GO, our board review programs are designed to mirror the way the NBEO tests—helping you build confidence through high-yield lectures, thousands of flashcards, comprehensive practice questions, clinical cases, and realistic patient encounter simulations.

Looking for a complete board review? See our NBEO Part 1 course.