Objective: The objective of this study was to analyze the secular trend of growth in height of military recruits enlisted in Blumenau and correlate it with the HDI index.
Methods: This was a cross-sectional study of recruits aged 18 to 20 enlisted to the 23rd Infantry Battalion in Blumenau between 1963 to 2007. The sample comprised 600 out of a total of 3000 recruits enlisted over the period. Data were collected from individual enlistment files on recruits which had been archived by year. Three years were analyzed from each decade (x3, x5, and x7) and the first forty files were selected systematically from each recruitment year for analysis. Statistical analysis was with descriptive statistics, Student's t test and simple linear regression.
Results: There was an increase of the order of 7 cm in the height of recruits in Blumenau over the last 47 years (from 1.7 meters in the 1960s to 1.77 meters in the 2000s) and the increase was most evident between the 1970s and 1980s. The mean heights in years in different decades exhibited a strong and positive correlation with the HDI in Blumenau and Brazil, which both increased progressively during the study period.
Conclusion: The secular tendency in growth in height was positive in Blumenau and had a positive correlation with HDI.