What is the significance of a confidence interval in test scores?

• A. It provides a definitive score with no error
• B. It provides a range of scores that likely includes the true score
• C. It eliminates measurement error entirely
• D. It indicates the minimum score required for passing

Answer: (B)

The significance of a confidence interval in test scores lies in its ability to provide a range of scores within which the true score is expected to lie. This concept is essential in measurement because it acknowledges the presence of variability and uncertainty in test results. Instead of providing a single score, a confidence interval takes into account potential errors in measurement, allowing interpreters to understand that the actual ability or trait being measured may fluctuate within a specified range.

For example, if a test score yields a confidence interval of 85 to 90, it suggests that there is a high likelihood that the individual's true score falls somewhere within this range, offering a more nuanced understanding of their performance. This is particularly useful in educational and psychological assessments, where stakes can be high, and the implications of a single number may be misleading.

In contrast, the other choices imply an unrealistic view of measurement. A definitive score without error, the complete elimination of measurement error, or a rigid passing score do not reflect the inherent complexities and uncertainties involved in testing. Thus, recognizing the confidence interval’s role emphasizes the importance of considering error margins when interpreting test scores.