{"id":7510,"date":"2024-08-27T15:43:36","date_gmt":"2024-08-27T15:43:36","guid":{"rendered":"https:\/\/neuropediatoolkit.org\/?p=7510"},"modified":"2024-11-04T17:23:37","modified_gmt":"2024-11-04T17:23:37","slug":"evaluacion-global-del-neurodesarrollo","status":"publish","type":"post","link":"https:\/\/neuropediatoolkit.org\/en\/evaluacion-global-del-neurodesarrollo\/","title":{"rendered":"Mathematics applied to the evaluation of neurodevelopment."},"content":{"rendered":"

(How to overcome dyscalculia from the neuropediatrician). <\/p>\n\n\n\n

Introduction.<\/h2>\n\n\n\n

Pediatric neurology is a discipline rooted within developmental medicine. As such, one of its main differential characteristics is that its subject of study is in flux, and any variable that wants to be studied is subject to this circumstance. The change variables<\/strong> continuous<\/strong> can be studied mathematically through derivatives, one of the branches of infinitesimal calculus<\/a>, mathematical concept historically attributed to Newton and Leibnitz. <\/p>\n\n\n\n

There are multiple developmental variables that can be interpreted as derivatives. Somatic growth (weight, height, head circumference), neurodevelopment (as a global measure, as well as as a measure of each of its domains, or even as a measure of certain cognitive modules), developmental biomarkers obtained by neuroimaging (development of cortical thickness, myelination, etc.).<\/p>\n\n\n\n

However, it is surprising how little familiarity we pediatric neurologists have with the use of developmental derivatives, such as the speed of development and the acceleration of development, and how little diffusion these concepts have in the literature, even though their use is widespread in other areas of pediatrics, such as in the assessment of the speed and acceleration of growth.<\/p>\n\n\n\n

In the information and \u201cbig data\u201d era, the assessment of neurodevelopment continues to use a classic clinical methodology based mainly on the subjective clinical impression of the professionals obtained during the consultation, even when we have quantification tools that would allow the application of much more powerful mathematical tools for its study.<\/p>\n\n\n\n

Not all tools provide us with the same information, and it is important that we choose those that best suit our objective. We do not intend to carry out a review of the tools available in this article, but it is necessary to point out several methodological reflections when selecting the optimal tool for use.<\/p>\n\n\n\n

In the present theoretical review we propose a systematization of the development terminology applicable to variables in change, through the study of their basic mathematical bases.<\/p>\n\n\n\n

Neurodevelopment and how to measure it.<\/h2>\n\n\n\n

The developmental scales divide neurodevelopment into different domains<\/strong>, which may differ from one assessment scale to another, so it is advisable to carry out the repeated measurements with the same tool<\/strong> in each subject, whenever possible.<\/p>\n\n\n\n

Neurodevelopment is a process hierarchical and synchronized<\/strong>, but not linear, but rather presents a pattern in \u201cwaves of development<\/strong>\u201d, with moments in which accelerations and decelerations occur. <\/p>\n\n\n\n

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Another phenomenon that we must take into account is that the variance of each of the developmental milestones is greater the older the child is, as can be seen (see below, the problem of heteroskedasticity).<\/p>\n\n\n\n

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The different development domains are interdependent between them<\/strong>. Thus, gross motor development chronologically precedes the development of language, as well as the development of fine motor skills and personal-social development, given that the development of some domains is a prerequisite<\/strong> for the development of others, or influences their appearance times significantly. <\/p>\n\n\n\n

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Developmental assessment tools are psychometric tests based on a normative population sample <\/strong>with which we are going to compare the individual who is the object of study. This means that we will use measurement tools to compare our study individual with the measurements obtained in said population at each moment of development, and to do so we will use standardized or standardized scores. There are different types of standardized scores, which can be transformed between them if we know the mean and standard deviation<\/strong>. <\/p>\n\n\n\n

After applying a development scale, we usually obtain a quantification of development in terms of equivalent developmental age<\/strong>. Knowing the chronological age of the subject evaluated, we can mainly perform 2 calculations: the difference in ages of development or chronological lag<\/strong> (resulting from the subtraction of the chronological age minus the developmental age) and the developmental quotient<\/strong> (resulting from the division of chronological age by developmental age, multiplied by one hundred). We will therefore be able to identify atypical neurodevelopment based on the degree of deviation observed with respect to their own chronological age (intra-individual matching<\/strong>).<\/p>\n\n\n\n

Some developmental scales (Battelle, Bayley III) also allow us to calculate the statistical position of our subject's results in relation to a healthy population sample previously evaluated with the same tool, through a standardized score, whether composite (mean 100 and SD 15), a z score (mean 0 and SD 1) or another type. Using a statistical definition of normality, we will be able to identify individuals who present atypical neurodevelopment in a much more precise and adequate way than with previous methods (inter-individual matching<\/strong>).<\/p>\n\n\n\n

As can be seen in the following graph, we can use these statistical data to calculate the relative position (z-score) of the individual under study at each moment of development.<\/p>\n\n\n\n

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