title: The Reproducibility and Relative Validity of a Mexican Diet Quality Index (ICDMx) for the Assessment of the Habitual Diet of Adults.
abstract: The study of diet quality in a population provides information for the development of programs to improve nutritional status through better directed actions. The aim of this study was to assess the reproducibility and relative validity of a Mexican Diet Quality Index (ICDMx) for the assessment of the habitual diet of adults. The ICDMx was designed to assess the characteristics of a healthy diet using a validated semi-quantitative food frequency questionnaire (FFQ-Mx). Reproducibility was determined by comparing 2 ICDMx based on FFQs (one-year interval). Relative validity was assessed by comparing the ICDMx (2nd FFQ) with that estimated based on the intake averages from dietary records (nine days). The questionnaires were answered by 97 adults (mean age in years = 27.5, SD = 12.6). Pearson (r) and intraclass correlations (ICC) were calculated; Bland-Altman plots, Cohen's κ coefficients and blood lipid determinations complemented the analysis. Additional analysis compared ICDMx scores with nutrients derived from dietary records, using a Pearson correlation. These nutrient intakes were transformed logarithmically to improve normality (log10) and adjusted according to energy, prior to analyses. The ICDMx obtained ICC reproducibility values ranged from 0.33 to 0.87 (23/24 items with significant correlations; mean = 0.63), while relative validity ranged from 0.26 to 0.79 (mean = 0.45). Bland-Altman plots showed a high level of agreement between methods. ICDMx scores were inversely correlated (p < 0.05) with total blood cholesterol (r = -0.33) and triglycerides (r = -0.22). ICDMx (as calculated from FFQs and DRs) obtained positive correlations with fiber, magnesium, potassium, retinol, thiamin, riboflavin, pyridoxine, and folate. The ICDMx obtained acceptable levels of reproducibility and relative validity in this population. It can be useful for population nutritional surveillance and to assess the changes resulting from the implementation of nutritional interventions.
authors: Academic group "Food and nutrition in health-disease process", Department of Human Reproduction, Growth and Child Development, Center of Health Sciences (CUCS), University of Guadalajara (UdG), Guadalajara, Jalisco 44100, Mexico. gaby_macedo@yahoo.com.mx.|Department of Public Health, Center of Health Sciences (CUCS), University of Guadalajara (UdG), Guadalajara, Jalisco 44100, Mexico. gaby_macedo@yahoo.com.mx.
authors: Gabriela
authors: G
authors: Macedo-Ojeda
authors: Academic group "Food and nutrition in health-disease process", Department of Human Reproduction, Growth and Child Development, Center of Health Sciences (CUCS), University of Guadalajara (UdG), Guadalajara, Jalisco 44100, Mexico. fabiola_msandoval@yahoo.com.mx.|Department of Public Health, Center of Health Sciences (CUCS), University of Guadalajara (UdG), Guadalajara, Jalisco 44100, Mexico. fabiola_msandoval@yahoo.com.mx.
authors: Fabiola
authors: F
authors: Márquez-Sandoval
authors: Preventive Medicine and Public Health, IISPV, Universitat Rovira i Virgili, Reus 43201, Spain. joan.fernandez-ballart@urv.cat.|CIBER Pathophysiology of Obesity and Nutrition (CB06/03) Instituto Carlos III, Madrid 28029, Spain. joan.fernandez-ballart@urv.cat.
authors: Joan
authors: J
authors: Fernández-Ballart
authors: Academic group "Food and nutrition in health-disease process", Department of Human Reproduction, Growth and Child Development, Center of Health Sciences (CUCS), University of Guadalajara (UdG), Guadalajara, Jalisco 44100, Mexico. bvizmanos@cucs.udg.mx.|Department of Public Health, Center of Health Sciences (CUCS), University of Guadalajara (UdG), Guadalajara, Jalisco 44100, Mexico. bvizmanos@cucs.udg.mx.
authors: Barbara
authors: B
authors: Vizmanos
mesh_terms: D000328:Adult; D004032:Diet / Q000592:standards; D015930:Diet Records; D004034:Diet Surveys / Q000592:standards*; D002149:Energy Intake; D005247:Feeding Behavior; D005260:Female; D005502:Food / Q000145:classification*; D006801:Humans; D008297:Male; D008800:Mexico; D015596:Nutrition Assessment; D015203:Reproducibility of Results
keywords: diet index; diet questionnaire; healthy diet; reproducibility; validity