T-scores are special scores that help us understand results from psychological tests. They show how a person’s performance compares to a larger group of people. This helps make sense of what the test results mean.

Important Points About T-Scores:

1. Standard Score: T-scores are created from regular scores using a specific method. This method takes into account the average score and the variation in the normative group. The formula to change raw scores into T-scores looks like this: $T = 10 \left( \frac{X - M}{SD} \right) + 50$ Here, ( X ) is the raw score, ( M ) is the average (mean) score of the group, and ( SD ) is how spread out the scores are (standard deviation).

2. Understanding Scores: The average T-score is 50, and the standard deviation is 10. This means:

   • A T-score above 50 shows better than average performance.
   • A T-score below 50 shows below-average performance.
   • For example, a T-score of 60 means someone did better than most, while a score of 40 means they did worse than most.

3. Percentile Comparison: T-scores can also tell us how someone compares to others in percentiles. For example:

   • A T-score of 60 usually means a person did better than about 84% of people in the group.
   • A T-score of 40 may mean they did better than about 16% of people.

Real-Life Uses:

• T-scores are very important in medical settings. Doctors use them for diagnosing issues, planning treatments, and checking how well someone is doing over time.
• T-scores help therapists explain test results clearly to their clients and others involved.

In simple terms, T-scores are a helpful way to understand and explain psychological test results. They allow professionals to see how someone stands out from the group in a clear and precise way.