An improved growth chart would use horizontal lines rather than curves, and would have no oblique lines to skew visual perception. Z-score growth charts accomplish this. Z-score growth charts are created using the same standardized data used to create the Fenton Growth Chart. Z-scores represent standard deviation scores. Rather than using a set of standard curves to represent average healthy growth, the z-score chart uses a single horizontal line. This allows for easier comparison when plotting a patient's weights over time. Such charts may lead to more accurate interpretation of overall growth patterns.