What is a Stanine Score?

What is a Stanine Score?

Lead consultant at Test Partnership, Ben Schwencke, explains what is a stanine score.

Stanine scores (short for “Standard Nine”) are standardized 1-9 scores commonly used in psychometric testing. Stanine scores allow psychometricians to convert rather abstract standardized scores into more interpretable numbers for a lay audience. As with other standardized scores, they are based on the average and distribution of scores for a specific population.

When using Stanine scores, scores between 1-3 are typically considered to be “low” scores, scores between 4-6 are often considered the “average” range, and scores 7-9 are considered “high” scores. Technically, Stanine scores theoretically can range from negative infinity to positive infinity, but the vast majority of data points in a normally distributed dataset will fall between 1-9. Traditionally, Stanine scores are reported as whole numbers rather than decimals.

Stanine scores are similar to percentiles, which are also used to report scores in a standardized way. Percentiles divide the distribution of scores into 100 parts, while Stanine scores divide the distribution of scores into 9 parts. By definition, the average Stanine score is 5, which is analogous to a percentile rank of 50. Stanine scores can be useful for setting broad pass marks or cut-scores, and are commonly used in educational and psychological testing.