v4.2.0

Update

• Trisomy 21 (AAP) reference added
• reorganisation of create_chart function - previously this would create centile lines by calculating a measurement for a given reference, measurement method, sex and z score at fixed decimal age intervals. This generated often uneven lines, particularly when growth velocity is quite steady. This update generates measurement for each interval in the data set meaning no interpolation between ages is necessary, making it quicker. It applies the default_youngest_reference flag more clearly, so that where references overlap and two values exist for a given age (eg at 2 y where infant are measured both lying and standing), a measurement for each is returned, allowing lines with clean breaks to be plotted with no gap. It also reduces the number of decimal places in the return object, again speeding things up.

NOTE: It is likely this latter change will break the tests for chart-coordinates in the server, so for the moment that is pinned to v4.1.1

NOTE: that although the T21 AAP reference has been added, there are no tests for this as there is currently no published gold standard - if anyone knows of one do please get in touch. The accuracy of results relating to this reference for the moment therefore cannot be guaranteed.