Revista Brasileira de Epidemiologia (Mar 2013)
Validade de peso, altura e índice de massa corporal autorreferidos na população adulta de Brasília Validity of self-reported height, weight and body mass index in the adult population of Brasilia, Brazil
Abstract
OBJETIVO: Avaliar a validade do peso, altura e índice de massa corporal (IMC) autorreferidos em adultos de Brasília e identificar os fatores associados às diferenças entre os valores medidos e autorreferidos. MÉTODOS: Em amostra por conglomerados de 250 domicílios foram aferidos peso e altura de todos os adultos residentes, após entrevista. A concordância entre os parâmetros medidos e autorreferidos foi feita por Bland & Altman (B&A). Utilizou-se análise de variância múltipla e estimou-se a sensibilidade e especificidade para o excesso de peso (IMC ? 25 kg/m2), estratificado por anos de estudo e faixa etária. RESULTADOS: As entrevistas e mensurações foram feitas em 469 indivíduos. Os resultados de B&A mostram viés (diferença dos valores medidos e autorreferidos) não significativo para o peso (-0,17 kg, p = 0,1) e significativo para a altura (-1 cm, p OBJECTIVE: To assess the validity of self-reported weight, height and body mass index (BMI) estimates from adults in Brasilia and to identify factors associated to differences between measured and self-reported values. METHODS: In a cluster sampling 250 household´s were selected and weight and height were measured in all adults after an interview. Bland & Altman (B&A) was used to determined agreement between measured and self-reported parameters. The multiple analysis of variance was used to determine the associated factors. Sensitivity and specificity were used for excess weight (BMI ≥ 25 kg/m2). RESULTS: Interviews and measurements were done in 469 individuals. B&A showed bias (difference between measured and self-reported values) was not significant for weight (- 0.17 kg, p = 0.1) and significant for height (- 1 cm, p < 0.001). The limits of agreement (LA) were wide: from ± 4 kg for weight and - 6 cm to 4 cm for height. BMI presented a non significant bias of - 0.06 kg/m2 (p = 0.08) and LA of - 1.5 to + 1.4 kg/m2. Men with a BMI < 25 kg/m2 overestimated weight, while overweight or obese men underestimated it (p < 0.01). Men older than 60y of age (p = 0.037) and women with less than 12y of study (p < 0.01) overestimated height. The sensitivity and specificity to detect excess weight were for men and women, respectively: 94%, 88% and 90%, 98%. Sensitivity to detect excess weight was 77% for 60 or over years old women and 75% for women between 9 to 11 years of study, while. specificity was 78% for men between 30 e 39 years old. CONCLUSION: In Brasilia, self-reported height can be used for subgroups of women with more than 12y of study and men under 60y of age. Men with adequate BMI over estimate their weight when compared to overweight and obese men. Self-reported measures can be used for excess weight population follow-up.
