A comparative study of two different methods of measuring stature and the velocity of growth in children and adults.

The stretched technique of measuring the stature described by Tanner (1962) is claimed to minimize the variation which occurs during the course of the day. This study examines differences in the calculated growth rate for the stretched and the conventional methods. The data for the analysis was drawn from a larger longitudinal growth study (Björk, 1968), where the stature of the individuals was measured both by the conventional unstretched technique according to Hrdlicka (1939) and by the stretched method described by Tanner (1962). A total of 84 individuals (48 boys and 36 girls) representing a total of 805 measurements of stature for each of the methods were included in the study. The individuals were measured annually until adult age, after which the measurements were made at intervals of 2-5 years. This represents a total range of 6-32 years of age, with individual series of observation varying over a period of 4-16 years. In accordance with the definition the stature measured by the stretched technique was significantly higher than measured by the unstretched method. The growth rate, however, at any age level did not differ significantly for the two methods and the variability in growth rate was the same. It was concluded that the unstretched technique gives similar values for estimating growth-velocity curves as does the stretched technique.