# 2009 John Wiley & Sons A/S Pediatric Diabetes Original Article Validation of capillary glycemia as a strategy for the screening of diabetes mellitus in adolescents Alvarez MM, Vieira ACR, Luiz RR, Veiga GV. Validation of capillary glycemia as a strategy for the screening of diabetes mellitus in adolescents. Objective: To compare the degree of concordance between plasma and capillary glucose for screening of diabetes mellitus in adolescents. Methods: The plasma and capillary glucose of 119 adolescents aged 10–19 yr (36 males and 83 females) from public schools in Nitero ´i, Rio de Janeiro State, Brazil, were verified after a 12-h fast. Agreement was assessed through kappa statistics (k), McNemar’s chi-squared test, and the intraclass correlation coefficient (ICC). The paired Student’s t-test for comparison of means, the approaches by Altman and Bland, and the survival–agreement plot were also applied. Results: Mean values of plasma glucose were 7.9 points higher than the capillary values (91.5 vs. 83.6 mg/dL, p , 0.001; ICC ¼ 0.419). A regular agreement between the methods (k ¼ 0.31, p , 0.001) for assessing proportions of adolescents with glycemia 100 mg/dL is observed. Using the strategy of adding 8 mg/dL to the capillary levels, the agreement improved (k ¼ 0.46, p , 0.001) and a significant difference was not observed between the estimated prevalences (p ¼ 0.815). Conclusions: The results suggest a satisfactory agreement between the two methods when capillary glucose is corrected, and this may be a useful and low-cost tool for the epidemiologic investigation of diabetes mellitus prevalence in adolescents. Marlene Merino Alvarez a,b , Ana Carolina Reiff e Vieira a , Ronir Raggio Luiz c and Glo ´ ria Vale ´ ria da Veiga a a Department of Nutrition, Instituto de Nutric xa ˜o Josue ´ de Castro, CCS, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; b Department of Nutrition, Anto ˆ nio Pedro Hospital, Universidade Federal Fluminense, Nitero ´i, Rio de Janeiro, RJ, Brazil; and c Institute of Public Health Studies, Universidade Federal do Rio de Janeiro, Prac xa Jorge Machado Moreira, Rio de Janeiro, RJ, Brazil Key words: adolescent – capillary glucose – diabetes – validation Corresponding author: Ronir Raggio Luiz Institute of Public Health Studies Federal University of Rio de Janeiro Prac xa Jorge Machado Moreira 100. Cidade Universita ´ ria 21941-598 Rio de Janeiro, RJ Brazil. Tel/fax: 155 21 2598 9278; e-mail: ronir@iesc.ufrj.br Submitted 19 October 2008. Accepted for publication 30 January 2009 Diabetes mellitus is considered one of the main causes of morbidity and mortality in the world. The Interna- tional Diabetes Federation estimated that in 2003, 194 million people have the disease and 65 000 children are affected by type 1 diabetes every year (1). Moreover, the number of cases of type 2 diabetes is growing among young people (2, 3), and this may be associated with the increase in the prevalence of overweight and obesity, which is observed in the developed countries (4) and developing countries as well (5). The obesity in youth was associated with insulin resistance and diabetes in adulthood (6) and in adolescence (7). Mainly in puberty, the decrease in sensitivity to insulin occurs, increasing the risk of an early development of type 2 diabetes (8). The American Diabetes Association (ADA) (3) recommends that the screening for type 2 diabetes in adolescents shall be performed by the measurement of plasma glucose in individuals with obesity and other risk factors, such as those who have a family history of diabetes or who belong to a specific ethnicity or show signs of insulin resistance. However, measurement of plasma glucose is not very practical for field studies as it requires the presence of trained laboratory profes- sionals and all the equipment for collecting and storing the blood. Hence, epidemiologic studies need the Pediatric Diabetes 2009: 10: 449 – 454 doi: 10.1111/j.1399-5448.2009.00508.x All rights reserved Pediatric Diabetes 2009: 10: 449 – 454. 449