Validity of Self-Reported Anthropometric Values Used to Assess Body Mass Index and Estimate Obesity in Greek School Children

Department of Physical Education and Sport Science, Democritus University of Thrace, Komotini, Greece. <>
Journal of Adolescent Health (Impact Factor: 3.61). 05/2007; 40(4):305-10. DOI: 10.1016/j.jadohealth.2006.10.001
Source: PubMed


To examine the validity of self-reported values of body height and weight, used for the estimation of body mass index (BMI), as a diagnostic method for the evaluation of overweight and obesity in Greek school children.
Self-reported height and weight was recorded and then measured in 378 primary (mean age 11.4 +/- .4 years) and 298 high school students (mean age 12.5 +/- .3 years). The BMI cutoff points adopted by the International Obesity Task Force were used to compare prevalence estimates of overweight and obesity obtained from self-reported and actual measures.
Significant differences were found between self-reported and measured anthropometric indices in all subgroups, except for height in elementary school girls. The degree of self-report bias did not differ between genders; however, it was higher for high school students and heavier children, compared to elementary school pupils and lighter children, respectively. Based on self-reports, prevalence estimates were 23.1% for overweight and 4.3% for obesity, but according to measured data the corresponding rates were 28.8% and 9.5%, respectively.
The present findings imply that the observed discrepancy between self-reported and measured anthropometric data in Greek children and adolescents might lead to erroneous estimating rates of overweight and obesity. Although self-reported data are easy to obtain, health surveys of overweight and obesity in youth need valid and accurate procedures.

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    • "On the basis of the HBSC study in Wales, in which measurements were made in parallel with the questionnaire [5], the authors point out that measured data are definitely needed in order to assess the magnitude of misclassification. A study of Greek school students came to the same conclusion [10]. It is recommended that the degree of misclassification in subgroups of children and adolescents be examined more closely by a validation study. "
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    ABSTRACT: Prevalence rates for overweight and obesity based on self-reported height and weight are underestimated, whereas the prevalence rate for underweight is slightly overestimated. Therefore a correction is needed. Aim of this study is to apply correction procedures to the prevalence rates developed on basis of (self-reported and measured) data from the representative German National Health Interview and Examination Survey for Children and Adolescents (KiGGS) to (self-reported) data from the German Health Behaviour in School Aged Children (HBSC) study to determine whether correction leads to higher prevalence estimates of overweight and obesity as well as lower prevalence rates for underweight. BMI classifications based on self-reported and measured height and weight from a subsample of the KiGGS study (2,565 adolescents aged 11-15) were used to estimate two different correction formulas. The first and the second correction function are described. Furthermore, the both formulas were applied to the prevalence rates from the HBSC study (7,274 adolescents aged 11-15) which are based on self-reports collected via self-administered questionnaires. After applying the first correction function to self-reported data of the HBSC study, the prevalence rates of overweight and obesity increased from 5.5% to 7.8% (compared to 10.4% in the KiGGS study) and 2.7% to 3.8% (compared to 7.8% in the KiGGS study), respectively, whereas the corrected prevalence rates of underweight and severe underweight decreased from 8.0% to 6.7% (compared to 5.7% in the KiGGS study) and from 5.5% to 3.3% (compared to 2.4% in the KiGGS study), respectively. Application of the second correction function, which additionally considers body image, led to further slight corrections with an increase of the prevalence rates for overweight to 7.9% and for obese to 3.9%. Subjective BMI can be used to determine the prevalence of overweight and obesity among children and adolescents. Where there is evidence of bias, the prevalence estimates should be corrected using conditional probabilities that link measured and subjectively assessed BMI from a representative validation study. These corrections may be improved further by considering body image as an additional influential factor.
    BMC Research Notes 03/2014; 7(1):181. DOI:10.1186/1756-0500-7-181
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    • "Third, using self-reported height and weight data may result in some inaccuracies. As shown in other studies, the use of self-reported weight and BMI tends to underestimate actual values, particularly in overweight women [48]. In addition, the self-reported weight at age 20 years relied on the mother's and the grandmother's memories, thereby increasing the risk of inaccuracy. "
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    ABSTRACT: Obesity may be the consequence of various environmental or genetic factors, which may be highly correlated with each other. We aimed to examine whether grandmaternal and maternal obesity and environmental risk factors are related to obesity in daughters. Daughters (n = 182) recruited from female students, their mothers (n = 147) and their grandmothers (n = 67) were included in this study. Multivariable logistic regression was used to analyze the association between the daughter's obesity and maternal, grandmaternal, and environmental factors. Maternal heights of 161-175cm (OD: 8.48, 95% CI: 3.61-19.93) and 156-160 cm (2.37, 1.14-4.91) showed positive associations with a higher height of daughter, compared to those of 149-155 cm. Mothers receiving a university or a higher education had a significant OR (3.82, 1.27-11.50) for a higher height of daughter compared to those having a low education (elementary school). Mother having the heaviest weight at current time (59-80 kg, 3.78, 1.73-8.28) and the heaviest weight at 20 years of age (51-65 kg, 3.17, 1.53-6.55) had significant associations with a higher height of daughters, compared to those having the lightest weight at the same times. There was no association between the height, weight, and BMI of daughters and the characteristics and education of her grandmothers. In conclusion, although genetic factors appear to influence the daughter's height more than environmental factors, the daughter's weight appears to be more strongly associated with individual factors than the genetic factors.
    Nutrition research and practice 10/2013; 7(5):400-8. DOI:10.4162/nrp.2013.7.5.400 · 1.44 Impact Factor
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    • "Study populations of adolescents are often characterised by a substantial proportion of missing values on height and weight [2-4]. Further, weight is often under-reported [5-13] while height tends to be over-reported [5,6,8,10,12,13]. Consequently, BMI is frequently underestimated leading to misclassification as some overweight individuals are classified as being normal weight. "
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    ABSTRACT: This study proposes a new approach for investigating bias in self-reported data on height and weight among adolescents by studying the relevance of participants' self-reported response capability. The objectives were 1) to estimate the prevalence of students with high and low self-reported response capability for weight and height in a self-administrated questionnaire survey among 11--15 year old Danish adolescents, 2) to estimate the proportion of missing values on self-reported height and weight in relation to capability for reporting height and weight, and 3) to investigate the extent to which adolescents' response capability is of importance for the accuracy and precision of self-reported height and weight. Also, the study investigated the impact of students' response capability on estimating prevalence rates of overweight. Data was collected by a school-based cross-sectional questionnaire survey among students aged 11--15 years in 13 schools in Aarhus, Denmark, response rate =89%, n = 2100. Response capability was based on students' reports of perceived ability to report weight/height and weighing/height measuring history. Direct measures of height and weight were collected by school health nurses. One third of the students had low response capability for weight and height, respectively, and every second student had low response capability for BMI. The proportion of missing values on self-reported weight and height was significantly higher among students who were not weighed and height measured recently and among students who reported low recall ability. Among both boys and girls the precision of self-reported height and weight tended to be lower than among students with low response capability. Low response capability was related to BMI (z-score) and overweight prevalence among girls. These findings were due to a larger systematic underestimation of weight among girls who were not weighed recently (-1.02 kg, p < 0.0001) and among girls with low recall ability for weight (-0.99 kg, p = 0.0024). This study indicates that response capability may be relevant for the accuracy of girls' self-reported measurements of weight and height. Consequently, by integrating items on response capability in survey instruments, participants with low capability can be identified. Similar analyses based on other and less selected populations are recommended.
    BMC Medical Research Methodology 06/2013; 13(1):85. DOI:10.1186/1471-2288-13-85 · 2.27 Impact Factor
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