February 3, 2021

Reducing Black and White Thinking: Constructing Partial Credit Multiple Choice Exams

by Lauryn Easley, PharmD, PGY1 Pharmacy Practice Resident, North Mississippi Medical Center

During my many years in school, exams were given primarily in the classic, multiple-choice question format. The form of assessment has been the gold standard for many years.1 While multiple-choice question examinations aren’t perfect, many would argue that “if it’s not broken, don’t fix it”. However, I would argue there is one significant shortcoming for the single best answer, multiple-choice tests —students begin to assume there is only one correct answer. This has led generations of students to view concepts with a “black or white” mentality. You are either right or you are wrong.  This kind of thinking is not helpful. Life is more nuanced. We need to help students understand that the world and our knowledge is actually rather grey.

In a world full of possibilities, leading our students to develop black and white thinking causes them to misunderstand situations. They only see the two extremes and not the in-betweens.1 Traditional multiple-choice examinations potentially stifle students’ creativity, as well as enable them to put forth minimal effort, thus producing lazy learners.1,2 If students were made to explain their reasoning or defend their choices, we could move away from simplistic answers and move towards students better able to stand by their viewpoints and use evidence to support them.1,2 Furthermore, multiple-choice exams inhibit the instructor’s ability to truly know whether the students fully grasp the concepts being taught. With traditional multiple-choice exams, students can guess the answers to most questions and still pass. A savvy test-taker might not actually comprehend the material.

Traditional multiple-choice tests can lead to “over-thinking” because the student assumes there is only one correct answer, even though other answer choices seem appropriate.2 As a type-A, over-thinker, I would find myself reading a question and looking for additional details to help make a complex decision.  But sometimes I was making the question far more complicated than the teacher intended. Because of this, I would sometimes pick an “incorrect” answer simply because I misunderstood what the teacher was asking me. In traditional multiple-choice exams, I had no way of explaining my reasoning.  I was forced to choose one answer over another. For this reason, I rarely reviewed questions I answered incorrectly on a test because I did not like to rehash my errors. Looking back, this was not a healthy mindset. None-the-less, I think it’s an important question. Should we move away from traditional multiple-choice exams, and if so, what are some suitable alternatives?

There are, in fact, a few different options, including awarding partial credit for answers that are okay but less than ideal, utilizing select all that apply questions, and short-answer questions.1,2,3

Partial credit focuses on awarding the most points to students picking the “most correct” or “best” answer but not fully penalizing students for picking an answer that may not have been the best option among the choices offered but is a reasonable option in some circumstances. Scoring questions in this manner can also help instructors move away from factual, straightforward, there is only one “right” answer to questions and move toward conceptual questions that require deeper thinking.1,2  For example, a question might ask about various treatment options for a disease or problem. While the “best” or “preferred” option might be among the choices, the student might be awarded partial credit for an option that is effective and unlikely to cause patient harm. In this case, the answer choice the student picked could be awarded partial credit, rather than full credit. The instills the idea that some answers are better than others but there is a range of “acceptable” choices. Other advantages of awarding partial credit – it may be easier for instructors to create distractors for the question and there may be fewer post-exam arguments from students seeking credit for their selected answers.

 Duckor and Holmberg give the example below to illustrate the benefits of organizing answer choices into bins, where certain bins are worth partial credit and other bins are considered incorrect.3


When the time is taken to organize and categorize each answer choice, instructors will have a better grasp of how well their students understand the topic, where common misconceptions lie, and where clarification with additional instruction may be beneficial. 

Select all that apply questions always discouraged me as a student because they were treated as all-or-nothing questions at my school.  You had to select ONLY the correct options and not select the incorrect options in order to get credit.  If you selected (or didn’t select) 5 out of the 6 options correctly, you go NO points. In other words, a student who got 5 out of 6 options correctly received the same number of points as a student who got 0 out of the 6 options correct.  It seemly likely the two students' understanding of the material is VERY different, but in terms of performance on the exam, they both received the same score. While some national certification examinations score select all that apply questions as all-or-nothing, this is not conducive to learning and doesn’t acknowledge what students DO know about the subject matter. To encourage students, they should be granted partial credit for each correct response option chosen and, conversely, points should be deducted for each incorrect option chosen. So, for example, if a student was correct on 5 out of 6 options, the student would receive +5 – 1 = 4 points.  If a student had 3 out of 6 options correct, the student would receive +3 – 3 = 0.  Awarding partial credit while also subtracting points for incorrect answers prevents students from gaming the system and simply selecting all options just to get some points.

As a student, I’ll admit that I didn’t like short-answer questions. However, in employing this testing format, we allow students to show us how much they understand and we can get a glimpse of each student’s thinking.1 Short-answer essay questions really require students to thoroughly prepare. The student is forced to formulate a response – they can’t rely on recall to select from a list of possible responses.  Short-answer essays can be combined with the multiple-choice format whereby the student must provide a rationale for the response they selected.  In this way, students must know the correct or “best” answers but also must defend their choice.1  Points could be independently awarded for selecting the correct answer and for the rationale.  Or points might be awarded only when the correct rationale is provided.  This would prevent “guessing” the correct answer.

I think these testing formats would encourage more students to review their responses to questions on an exam and encourage them to fully grasp the concepts being tested. It could lead more students to dig deeper into the materials to assess why they missed certain questions and why the best answer was, in fact, better than the other choices.

While a majority of these testing options may require more time and effort for either preparing or grading examinations, they give us a much clearer picture of how our students are doing and how well they grasp the material.1,2 More importantly, rather than reinforcing black and white thinking, these alternative exam formats promote critical thinking, encouraging students to weigh the merits of different options.

References: 

  1. Harrnstadt D. Pivot away from multiple-choice testing [Internet]. Bethesda (MD): Walt Whitman High School, The Black & White; 2019 Mar 23 [cited 2021 Jan 28].
  2. Berwick C. What Does the Research Say About Testing? [Internet]. San Rafael (CA): George Lucas Educational Foundation, Edutopia; 2019 Oct 25 [cited 2021 Jan 28].
  3. Duckor B, Holmberg C. Two Strategies for Assessing for Learning: The Partial Credit Scoring Key and the Scoring Guide [Internet]. Alexandria (VA): Association for Supervision and Curriculum Development, Inservice; 2018 Jul 23 [cited 2021 Jan 28].

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