In nutrition studies, you will often see z-scores used as a way to compare the data from the study to “normal” data (e.g., comparing anthropometric measures against a standard growth chart). The mean of the normal data is always represented as zero and the distance from the mean is represented as positive or negative numbers, beginning with “1.” Nearly all infants (95%) in a population will be within -2.0 and +2.0 z-scores. These values are generally used to evaluate anthropometric measures.
Z-scores are important to your HCPs because they allow them to see how the data in your study compares to or deviates from a reference standard (such as a growth chart). These scores will also help HCPs to interpret and assess the results of your study in the context of information they currently use in their clinical practice.