Adult-Gerontology Clinical Nurse Specialist (CNS) Practice Exam

In statistical analysis, which statement about skewness is inaccurate?

1. Any curve that is not symmetrical is referred to as skewed

2. A curve may be positively skewed or negatively skewed

3. Skewness interferes with the validity of many statistical analyses

4. In a skewed distribution, the mean, median, and mode are equal

The correct answer is: In a skewed distribution, the mean, median, and mode are equal

The assertion that in a skewed distribution, the mean, median, and mode are equal is inaccurate. In fact, one of the defining characteristics of skewed distributions is that these three measures of central tendency do not coincide. In a positively skewed distribution, for instance, the tail on the right side is longer than that on the left. This results in the mean being greater than both the median and the mode. Conversely, in a negatively skewed distribution, where the tail is longer on the left, the mean is less than both the median and the mode. This distinctive relationship among the mean, median, and mode in skewed distributions serves as an essential tool for understanding the nature of the data. Recognizing that skewness leads to different positional relationships between these measures is fundamental in statistical analysis, especially when choosing appropriate methods for data interpretation and analysis. This reinforcement of understanding the nature of distributions plays a critical role in ensuring the accuracy and validity of any statistical conclusions drawn from the data.