Ensuring the Accuracy of Your Assessment Results: A Guide to Validity and Reliability

Validity and reliability are both essential concepts when it comes to assessments. Both are similar in that they are related to the quality of assessment results, but they have distinct meanings and ultimately serve different purposes. Making wise choices regarding student learning and ensuring the outcomes of these assessments can be trusted depends on the validity and reliability of an assessment tool.

Understanding the significance of validity and reliability in assessments is critical, regardless of whether you are a teacher, a student, or someone else who utilizes assessments in their work. This is because when assessments are valid and reliable, the assessing, grading, and reporting practices are much more equitable. Equitable practices are especially important after setbacks in student performance and test scores from the impact remote learning had on learning.

Education is an ever-evolving system. As students and curriculum evolve, so must assessments. When entering into a new year of teaching, the data gathered from the previous year’s assessments is crucial to improving learning. Our EDVIEW360 podcast series discussed this in relation to moving into a new year with previous test results: “It's really crucial because that assessment data is really going to help inform the teacher on what to do with those students so that he or she can really help to move their learning along a path for growth in such a unique year when it comes to education,” said Kristen Biadasz, former senior product marketing manager at Voyager Sopris Learning®. It is this path for growth that all teachers strive for, which can be better paved with valid and reliable assessments. 

Validity in Assessment

Validity, according to Merriam-Webster, is “the quality of being well-grounded, sound, or correct.” When it comes to education and assessments, validity is a measure of how true the outcomes of an assessment are. Assessments themselves must be well-grounded, sound, and correct so the results are sound and correct as well. Ensuring an assessment’s validity guarantees the findings are trustworthy.

Assessments are much more than just a rubric, and therefore internal consistency of content, construction, and criterion must all be taken into account when creating valid assessments.

Test validity is important when it comes to assessing students. Educators should strive to ensure assessments are actually measuring what they claim to measure. Three of the most common types of validity in assessments are content validity, construct validity, and criterion-related validity. 

Content Validity

Content validity measures how well an assessment covers the content it is intended to measure. Content is a huge focus in the classroom when it comes to choosing curriculum, and it is an equally important component to consider in the validity of assessments. If a test does not accurately assess the actual content, then the full range of knowledge, skills, or abilities of a student relating to that content will not be fully reflected in the results.

Construct Validity

Construct validity deals more with measuring complex constructs. If content validity is more of the “what” in assessments, then construct validity is more of the “how.” For example, many achievement tests aim to measure complex constructs like reading comprehension, critical thinking, and problem solving.

Criterion-Related Validity

Lastly, criterion validity evaluates how adequately an assessment measures or predicts the outcome it was intended to measure. This type of validity can be divided further into two types: concurrent validity and predictive validity. Concurrent validity identifies how an assessment tool correlates with criterion in the present, and predictive validity identifies how an assessment tool predicts future performances or behavior.

Reliability in Assessment

While validity refers to the accuracy of assessment, reliability deals more with the consistency of assessment. Reliability, in a sense, falls under the umbrella of validity. Reliability is defined as “the quality of being trustworthy or of performing consistently well.” An assessment must be consistent itself if it is expected to produce consistent, valid results.

There are many different aspects when it comes to ensuring the reliability and accuracy of evaluation outcomes. When we begin discussing reliability, terms like “coefficient” and “correlation coefficient” are often used.

Reliability measures whether or not an assessment tool provides the same results each time it is used with the same surrounding factors. Types of reliability can come down to either internal or external factors. External reliability measures consistency across outside conditions, and internal reliability measures consistency within itself.

Test-Retest Reliability

Test-retest reliability involves measuring the consistency of an assessment over time. This can be found by administering the same assessment to the same group of students at two different times and then correlating the two scores. It can be challenging to administer the same assessment in the same exact conditions and scenario two times in a row, which leaves some room for error. However, if done well, a test-retest assessment can accurately measure true growth in the skill and ability of the test taker.

Inter-Rater Reliability

Inter-rater reliability involves the consistency between those rating or scoring an assessment. Consistency here looks like different raters providing similar scores or ratings when assessing the same skill or behavior. This can be challenging because of the potential subjective nature of scoring. For example, essays are harder to grade consistently than multiple-choice assessments.

Internal Consistency Reliability

While test-retest and inter-rater are both forms of external reliability, internal consistency reliability is, as the name suggests, internal. This type of reliability involves identifying the consistency between multiple questions dealing with the same content or concept within the assessment. This can be calculated using a statistic called Cronbach’s alpha, in which a higher Cronbach’s alpha value indicates greater internal consistency. Internal consistency is important to ensure an assessment is not contradicting itself and subsequently producing inconsistent and contradictory results.

Methods to Ensure Validity and Reliability in Assessment

Assessments are a crucial component in tracking students’ academic progress. However, a test must be both valid and reliable to be useful. Many educational organizations have made a push for more accountability in these areas, forming campaigns and committees dedicated to help. For example, in 2018, the American Educational Research Association commended the National Center for Education Statistics (NCES) for appointing a new commissioner, stating, “Accurate, independent, timely, useful, and reliable statistics and data from pre-K through higher education and the workforce are bedrock nationally and internationally for understanding the conditions of education and the impact of policies.” 

The impact of these assessments and their results go beyond just education. For example, the American Psychological Association discusses the reliability and validity of Spanish language assessment of children’s social-emotional learning skills. The push for reliable and valid assessments in not only academic content but also social-emotional comprehension are areas that continue to grow today. Therefore, the American Educational Research Association (AERA), American Psychological Association (APA), and National Council on Measurement in Education (NCME) all collectively developed a set of “Standards for Educational and Psychological Testing,” which is viewed as the gold standard on testing nationally and internationally. 

To keep this field of study and implementation growing, there are a number of different methods teachers can use to ensure validity and reliability in assessment. Incorporating these methods at all stages of the assessment process—before, during, and after—provides a comprehensive approach to making sure an assessment is dependable and consistent.

Pilot Testing

The process of administering an assessment to a small group before using it on a larger scale is called pilot testing, which allows those creating or providing the test to evaluate the assessment, identify any issues or problems, and make changes to ensure the validity and reliability of the assessment. This is an important step to conduct before an official assessment takes place because it can provide data that helps identify faulty questions, confusing instructions, or administrator biases that might lead to insufficient test results.

Standardized Administration

Once an assessment has been pilot tested with a smaller group of individuals, standardized administration helps ensure the process of assessing is uniform and consistent for all individuals. Standardized test administration creates a test environment in which everything is the same, from the spacing of the desks, to the timing of the assessment, to the questions themselves. The ACT and the SAT are great examples of standardized administration of a test that is the same across the board for all test takers.

Ongoing Monitoring and Review

Even after an assessment is administered, it is not necessarily over and done. Keeping a continuous process of monitoring and evaluating assessments is important to leave room for improving assessment validity and reliability. For example, taking the time to collect and analyze data, accept feedback from people involved in the assessment, and make subsequent changes based on the data and feedback will help ensure the assessment continues to remain a valid and reliable assessment over time.

Conclusion: The Importance of Validity and Reliability in Assessment

Assessment results help shape and guide further education, which is why these results must be dependable. To get dependable results, the assessment tool must be valid and reliable. 

There is a need for validity and reliability in our assessments, and there is a need for aligning assessments to meet schoolwide needs. By bettering our assessments, we are bettering our entire education system. Voyager Sopris Learning offers a suite of valid and reliable assessment solutions for educators to assess their students effectively.