Within the national sample, a 10% subsample of the children included in it was randomly selected for an X-ray of the left hand. In total, a minimum of 100 X-rays was obtained for each sex and each year of age, reaching an approximate total of 5,000. A single observer evaluated them using the Tanner-Whitehouse system. Bone maturation standards are now available, together with their corresponding percentile curves.
Cuban growth and development curves and tables have been progressively introduced into pediatric practice at different levels of the national health system. All children below the 10th percentile and above the 90th percentile according to the standards of weight for height and height for age must be carefully examined by a pediatrician. This requirement is based on the fact that they are atypical for the population norm, although not necessarily abnormal, and the risk criterion is applied to them. Similarly, when an unexpected deviation within a child’s growth channel is observed during periodic follow-up, the causes must be investigated.
Growth standards or patterns are often used as if they represented optimal biomedical reference data. It is therefore necessary to draw the attention of pediatricians, general practitioners and nurses to the fact that growth curves should be used only as a case-finding test, and that a careful clinical examination is required in order to make a definitive diagnosis of the child’s health status.
The evaluation of each case must be based not only on growth charts, but also on additional information: the course of growth in repeated examinations, the height of both parents, whether the child was small at birth, and other factors. An isolated observation is often insufficient for a definitive diagnosis.
Moreover, during adolescence, an individual’s growth does not follow the curve based on a cross-sectional study. Adolescents who mature early sexually rise sharply in height above the percentile they had been following, while those who mature late descend and gradually move to a lower channel before later rising and returning to their original or a higher channel.
These biological facts, with their normal variations, must be known by the patients themselves, their parents, classmates and teachers, and should not cause unnecessary concern. It is in these circumstances that standards of sexual development and bone maturation are very useful, because they make it possible to affirm that this situation is actually temporary and only a variant of normal development.
This information is highly useful for application in the school system and in collective sports practice, where children should perhaps be separated into categories that take into account not only chronological age, but also biological age or maturation age.
After careful evaluation and testing in different areas of the country, Cuba’s growth and development standards have been incorporated into the national health system for application in primary care, and have become one of the factors that define the concept of risk in pediatric care.
Since it has been found that approximately 50% of the Cuban population is of African ancestry, it is likely that the data presented may be useful for populations with similar genetic traits.
Studies of population growth and development have shown their value not only as health indicators for the individuals who make up that population, but also as important information regarding environmental factors that may have an unfavorable impact on different population groups with similar genetic material.
It should also be noted that they have applications in different branches of the economy, such as industrial design and the production of goods including furniture, clothing, footwear and others.
In 1982, the survey was repeated, exactly 10 years after the first one. In this second study, the same anthropometric dimensions were recorded in order to compare them with the previous study, along with additional measurements to be applied to body composition and somatotype.
In addition, children under six years of age were given the Denver test; in those older than 3.5 years, motor performance was studied through different tests, such as running, long jump and high jump, and functional capacity was assessed using the step test and the bicycle ergometer.
This information is currently being processed. The comparison of data from the two surveys, with an interval of 10 years, will provide information of extraordinary value on health and development. We will stop measuring only disease and mortality in order to also devote ourselves to measuring health.
