How Is the OAT Scored?

If you are considering optometry as a profession, the optometry admission test (OAT) is an important standardized exam you will have to take. The OAT is a 5-hour test required by most optometry schools for admission. Therefore, it plays an important role in optometry schools’ admission decisions and adequate preparation should be completed to increase your chances of being accepted. It is best to figure out how the exam works and what score you should be aiming for. In this article, we will cover how the OAT is scored, what the average OAT score is, and what defines a good OAT score for admission to optometry school.

I. How Is the OAT Scored?

The OAT is made up of 4 general sections: natural sciences, physics, quantitative reasoning, and reading comprehension. The natural sciences portion is made up of 3 subsections: biology, general chemistry, and organic chemistry. Each section is allocated a certain number of multiple-choice questions that must be completed in a specific amount of time before moving onto the next section. The number of questions and time allocated for each section are shown in the table below:

•   Raw Score: You will be given a raw score for each section of the OAT. The raw score is the number of correct answers out of the total number of questions in each section. Each multiple-choice question is worth 1 point and there is no penalty for answering questions wrong. For example, if you get 30 questions correct out of the total 40 questions in the biology section, your raw biology score will be 75%.
• Standard Score: After the raw scores are calculated, they are converted to scaled or standard scores. The standard scores range from 200 to 400, and they are reported in increments of 10. They are the scores that show up on your official report and are sent to optometry schools for your applications. The OAT is not scored on a curve, and these standardized scores allow for accurate comparison between applicants who write the OAT at different times.
  • Total Science (TS) score: On your official results, you will also see a Total Science (TS) score. This is the total number of science questions (Biology, General Chemistry, Organic Chemistry and Physics) answered correctly, converted to a standard score.
  • Academic average (AA) score: You will also see an Academic Average (AA) score. This is the average value of the standard scores of all 6 sections.

Furthermore, the table below shows an example OAT score conversion table from a raw score to a standard score, but please note it can vary depending on the version of the exam you get. For example, 37 questions answered correctly out of 40 on the Biology section may result in a standard score of 400. However, note that there are different versions of the OAT and the conversion chart can vary slightly. This depends on the version’s level of difficulty deemed by the Association of Schools and Colleges of Optometry (ASCO).

• Percentile Ranking: On your score report, you will also be given a percentile ranking. This number is reported in increments of 10 and shows the percentage of other test takers that performed similarly or worse than you on specific sections. For example, if you are in the 90th percentile for the biology section, it means that 90% of other test-takers scored just as well or worse than you on the biology questions, while only 10% performed better. However, the percentile rank is not a standardized value – it can change depending on the number of test-takers each year and how well you performed in comparison.

II. What Is the Average OAT Score?

With your performance on the OAT in mind, you must be thinking: What is the mean OAT score and how can I perform better than the average score?

According to the ASCO, the mean standard score for the OAT is 300, with a standard deviation of 40. This score corresponds with the 50^th  percentile, meaning 50% of other test-takers perform just as well or worse than you, while 50% perform better than you. As shown in the chart below, the mean standard AA and TS scores of the entering class profiles of US optometry schools have stayed relatively consistent, around a score of 320 from 2010 to 2020. Any fluctuations from the ideal mean are closely monitored by the ASCO and if a significant drift occurs, the test will be recalibrated to set the mean back to 300.

Source: Profiles of the 2010-2020 Optometry Entering Classes, published online by the Association of Schools and Colleges of Optometry

However, note that the average OAT score is not always 300. Because the OAT is a large-scale test held across North America, there will always be variations due to different factors. Even more, these factors help define a good OAT score for optometry school admission. To learn more information about exactly what is considered a good score on the OAT, check out our article.

III. Conclusion

Although optometry school applications encompass more than just a test score, the OAT is an important metric for admission. Therefore, it is best to look into the schools you want to apply to and check their admitted class profiles. You want to have an idea of what you are getting into and what score to aim for. This way, you can allocate enough time to find the right resources and properly prepare to excel on the OAT. Good luck!