This was one of the first of many articles publishing research demonstrating the severe limitations of using commercially available child language tests when assessing children for speech and language disability.
This study presented the findings and implications for clinicians, educators, and policy makers after recording all interactions between caregivers and children, from age 7 months to 3 years old, in different socioeconomic classes for 1 hour per week.
A normal distribution, also called a bell curve, occurs when variables (i.e., test scores) plotted on a graph fall into a regular distribution around a single mean. In a normal distribution, about 96% of the scores will fall within 2 standard deviations of the mean.
Linguistic bias can be bias towards speakers of other languages or dialects, or towards bilingual speakers and results in inaccurate assessment of children from linguistic backgrounds other than Standard American English.
A standard deviation (SD) is a quantity derived from the distribution of scores from a normative sample and can be defined as the average distance (or deviation) from the mean.
The percentile rank of a score is percentage of total scores from the normative sample that were equal or lesser than the value of the score and can be plotted on the bell curve of a normal distribution.
The terms normative sample and standardization sample refer to the same concept and are often used interchangeably. A norm referenced test uses a normative or standardization sample from the general population to determine what is “typical” or “normal” in that population.
The standard error of measure indicates the amount of uncertainty that a sample (such as a normative sample) is truly representative of the general population. In the case of administering standardized tests, it conveys the level of uncertainty that a single test performance observed by the evaluator represents how the child would do if it were administered multiple times.
