Which of the following is an example of a percentile rank used in the context of SSD assessment?

• A. A z-score of -2.0
• B. A standard score of 100
• C. A percentile rank of 12
• D. A raw score of 23

Answer: (C)

Percentile ranks express where a score sits relative to a normative group, showing the percentage of peers scoring below that point. In SSD assessment, clinicians often use them to interpret how a child’s performance compares to typical development. A percentile rank of 12 means the child performed better than only 12 percent of children in the reference sample, placing them in the lower portion of the distribution. This direct percentile-based interpretation is what percentile ranks provide.

The other options reflect different kinds of reporting: a z-score of -2.0 indicates how far the score is from the mean in standard deviation units, not a percentile; a standard score of 100 is a normalized score with a fixed mean and SD, not a percentile; and a raw score of 23 is just the raw count of correct items, without reference to how it ranks among peers.