Childhood Overweight Prevalence in the United States: The Impact of Parent‐reported Height and Weight

Parent‐reported height and weight are often used to estimate BMI and overweight status among children. The quality of parent‐reported data has not been compared to measured data on a national scale for all race/ethnic groups in the United States. Parent‐reported height and weight for 2–17‐year‐old children in two national health interview surveys—the 1999–2004 National Health Interview Survey (NHIS) and the 2003–2004 National Survey of Children's Health (NSCH)—were compared to measured values from a national examination survey—the 1999–2004 National Health and Nutrition Examination Survey (NHANES). Compared to measured data, parent‐reported data overestimated childhood overweight in both interview surveys. For example, overweight prevalence among 2–17‐year‐olds was 25% (s.e. 0.2) using parent‐reported NHIS data vs. 16% (s.e. 0.6) using measured NHANES data. Parent‐reported data overestimated overweight among younger children, but underestimated overweight among older children. The discrepancy between reported and measured estimates arose mainly from reported height among very young children. For children aged 2–11 years, the mean reported height from NHIS was 3–6 cm less than mean measured height from NHANES (P < 0.001) vs. no difference among children aged 16–17 years. Measured data remains the gold standard for surveillance of childhood overweight. Although this analysis compared mean values from survey populations rather than parent‐reported and measured data for individuals, the results from nationally representative data reinforce previous recommendations based on small samples that parent‐reported data should not be used to estimate overweight prevalence among preschool and elementary school–aged children.     

The obesity epidemic and changes in self‐report biases in BMI

Objective:

To assess time trends in measurement error of BMI and the sensitivity/specificity of classifying weight status in the United States by analyzing the difference in BMI between self‐reported and measured height and weight.

Design and Methods:

Data from 18,394 respondents aged 20‐89 years from the National Health and Nutrition Examination Survey (NHANES) from 1999 through 2008 were analyzed. Multiple linear regression and logistic regression models estimated trends in reporting bias and misclassification of weight status by BMI categories, sex, age, and racial/ethnic groups, adjusting for the sampling design.

Results:

We find no evidence that there are time trends in the accuracy of self‐report by BMI categories, sex, age, or racial/ethnic groups. The well‐known downward bias in self‐report has remained stable over the last decade; approximately one in six to seven obese individuals were misclassified as nonobese due to underestimation of BMI.

Conclusion:

Increases in obesity rates based on self‐reported height and weight are likely to reflect actual weight increases and are not inflated by changes in reporting accuracy.     

High Rates of Obesity and Chronic Disease Among United Methodist Clergy

We used self‐reported data from United Methodist clergy to assess the prevalence of obesity and having ever been told certain chronic disease diagnoses. Of all actively serving United Methodist clergy in North Carolina (NC) 95% (n = 1726) completed self‐report height and weight items and diagnosis questions from the Behavioral Risk Factor Surveillance Survey (BRFSS). We calculated BMI categories and diagnosis prevalence rates for the clergy and compared them to the NC population using BRFSS data. The obesity rate among clergy aged 35–64 years was 39.7%, 10.3% (95% CI = 8.5%, 12.1%) higher than their NC counterparts. Clergy also reported significantly higher rates of having ever been given diagnoses of diabetes, arthritis, high blood pressure, angina, and asthma compared to their NC peers. Health interventions that address obesity and chronic disease among clergy are urgently needed.     

The geographic distribution of obesity in the US and the potential regional differences in misreporting of obesity

Objective: State‐level estimates of obesity based on self‐reported height and weight suggest a geographic pattern of greater obesity in the Southeastern US; however, the reliability of the ranking among these estimates assumes errors in self‐reporting of height and weight are unrelated to geographic region. Design and Methods: Regional and state‐level prevalence of obesity (body mass index ≥ 30 kg m^?2) for non‐Hispanic black and white participants aged 45 and over were estimated from multiple sources: ( 1 ) self‐reported from the behavioral risk factor surveillance system (BRFSS 2003‐2006) (n = 677,425), ( 2 ) self‐reported and direct measures from the National Health and Nutrition Examination Study (NHANES 2003‐2008) (n = 6,615 and 6,138, respectively), and ( 3 ) direct measures from the REasons for Geographic and Racial Differences in Stroke (REGARDS 2003‐2007) study (n = 30,239). Results: Data from BRFSS suggest that the highest prevalence of obesity is in the East South Central Census division; however, direct measures suggest higher prevalence in the West North Central and East North Central Census divisions. The regions relative ranking of obesity prevalence differs substantially between self‐reported and directly measured height and weight. Conclusions: Geographic patterns in the prevalence of obesity based on self‐reported height and weight may be misleading, and have implications for current policy proposals.     

From “Overweight” to “About Right”: Evidence of a Generational Shift in Body Weight Norms

In this article, we describe differences in the self‐perception of weight status in the United States between the two most recent National Health and Nutrition Examination Survey (NHANES) periods (1988–1994 and 1999–2004), and test the hypothesis that secular increases in adult mean BMI, adult obesity, and childhood obesity contributed to changes over time in weight perceptions. We find that the probability of self‐classifying as overweight is significantly lower on average in the more recent survey, for both women and men, controlling for objective weight status and other factors. Among women, the decline in the tendency to self‐classify as overweight is concentrated in the 17–35 age range, and is more pronounced among women with normal BMI than those with overweight BMI. Among men, the shift away from feeling overweight is roughly equal across age groups. Overweight men exhibit a sharper decline in feeling overweight than normal weight men. Despite the declines in feeling overweight between surveys, weight misperception did not increase significantly for men and decreased by a sizable margin among women. We interpret the findings as evidence of a generational shift in social norms related to body weight. As a result, people may be less likely to desire weight loss than previously, limiting the effectiveness of public health campaigns aimed at weight reduction. On the other hand, there may be health benefits associated with improved body image.     

The validity of obesity based on self-reported weight and height: Implications for population studies

Objective: To validate self‐reported information on weight and height in an adult population and to find a useful algorithm to assess the prevalence of obesity based on self‐reported information. Research Methods and Procedures: This was a cross‐sectional survey consisting of 1703 participants (860 men and 843 women, 30 to 75 years old) conducted in the community of Vara, Sweden, from 2001 to 2003. Self‐reported weight, height, and corresponding BMI were compared with measured data. Obesity was defined as measured BMI ≥ 30 kg/m². Information on education, self‐rated health, smoking habits, and physical activity during leisure time was collected by a self‐administered questionnaire. Results: Mean differences between measured and self‐reported weight were 1.6 kg (95% confidence interval, 1.4; 1.8) in men and 1.8 kg (1.6; 2.0) in women (measured higher), whereas corresponding differences in height were ?0.3 cm (?0.5; ?0.2) in men and ?0.4 cm (?0.5; ?0.2) in women (measured lower). Age and body size were important factors for misreporting height, weight, and BMI in both men and women. Obesity (measured) was found in 156 men (19%) and 184 women (25%) and with self‐reported data in 114 men (14%) and 153 women (20%). For self‐reported data, the sensitivity of obesity was 70% in men and 82% in women, and when adjusted for corrected self‐reported data and age, it increased to 81% and 90%, whereas the specificity decreased from 99% in both sexes to 97% in men and 98% in women. Discussion: The prevalence of obesity based on self‐reported BMI can be estimated more accurately when using an algorithm adjusted for variables that are predictive for misreporting.     

Ethnic Differences in Self‐reported and Measured Obesit

As use of self‐reported data to classify obesity continues, ethnic differences in reporting errors remain unclear. The objective of this study is to elucidate misreporting disparities between African Americans (AAs) and European Americans (EAs). The Pennington Center Longitudinal Study (PCLS) is an ongoing investigation of environmental, behavioral, and biological factors associated with obesity, diabetes, and other common diseases. Self‐reported and measured height and weight were collected during initial screening for eligibility in various studies by telephone and clinic visits. All ethnicity‐sex groups (15,656 adults aged 18–65 years, 53% obese, 34% AA, 37% men) misreported heights and weights increasingly as measured values increased (P < 0.0001). More AA vs. EA women (P < 0.001) misreported height and weight, but more EA vs. AA men misreported their weight (P < 0.02). Obesity was underestimated more in AA vs. EA women (self‐reported ? measured prevalence = ?4.0% (AA) vs. ?2.6% (EA), P < 0.0001), but less in AA vs. EA men (?3.2% (AA) vs. ?4.2% (EA), P < 0.0001)). With measured obesity prevalence equalized at 53% in all groups, the self‐reported obesity prevalence in women was 50.4% (AA) vs. 49.6% (EA), and in men 49.8% (AA) vs. 47.3 (EA). Underestimation in women was ?2.6% (AA) vs. ?3.4% (EA); in men it was ?3.2% (AA) vs. ?5.7% (EA), P < 0.003. Self‐reported height and weight portend underestimation of obesity prevalence and the effect varies by ethnicity and gender. However, comparisons depend on the true prevalence within ethnicity‐gender groups. After controlling for obesity prevalence, disparity in underestimation was greater in EA than in AA men (P < 0.003) but not women.     

Changes in perceived weight discrimination among Americans, 1995-1996 through 2004-2006

Objective: Little is known about the prevalence and patterns of weight discrimination in the United States. This study examined the trends in perceived weight/height discrimination among a nationally representative sample of adults aged 35–74 years, comparing experiences of discrimination based on race, age, and gender. Methods and Procedures: Data were from the two waves of the National Survey of Midlife Developmentin the United States (MIDUS), a survey of community‐based English‐speaking adults initially in 1995–1996 and a follow‐up in 2004– 2006. Reported experiences of weight/height discrimination included a variety of settings in major lifetime events and interpersonal relationships. Results: The prevalence of weight/height discrimination increased from 7% in 1995–1996 to 12% in 2004–2006, affecting all population groups but the elderly. This growth is unlikely to be explained by changes in obesity rates. Discussion: Weight/height discrimination is highly prevalent in American society and increasing at disturbing rates. Its prevalence is relatively close to reported rates of race and age discrimination, but virtually no legal or social sanctions against weight discrimination exist.     

Correlates of BMI misreporting among apparently healthy individuals: the ATTICA study

Objective: The aim of this study was to investigate correlates of misreporting in BMI, based on self‐reported weight and height, in a randomly selected population sample of Greek adults and to evaluate the effect of obesity status misclassification on the associations between obesity and disease. Research Methods and Procedures: During 2001 to 2002, we randomly enrolled 1514 men (18 to 87 years old) and 1528 women (18 to 89 years old) from the Attica area, Greece; the sampling was stratified by the age‐sex distribution of the region. Various sociodemographic, clinical, and psychological characteristics were self‐reported, and weight and height were measured and recorded in all participants. Results: The proportions of true positives and true negatives for correct obesity status identification were 62% and 97%, respectively. Women were 9 times more likely to be under‐reporters than men, whereas men were 7.5 times more likely to be over‐reporters. A 10‐year increase in age was associated with a 48% higher likelihood of being an under‐reporter and 26% lower likelihood of being an over‐reporter, irrespective of sex and other characteristics of the participants. Clinical status, such as the presence of hypertension and diabetes, was associated with under‐reporting of body weight. Furthermore, the use of self‐reported data may substantially exaggerate associations between obesity and obesity‐related diseases, such as diabetes, hypercholesterolemia, and hypertension. Discussion: The study indicates that, apart from age and sex, disease status may be another factor that influences misreporting of obesity status, with diabetic and hypertensive people to be more likely to under‐report their overweight. Use of self‐reported data may bias obesity—disease associations.     

Geographic Variation in the Prevalence of Obesity,Diabetes, and Obesity‐Related Behaviors**

Objective: To examine the variation in the prevalences of obesity and type 2 diabetes in weight loss counseling by health providers and in other potential obesity‐related determinants in 100 metropolitan statistical areas in the United States. Research Methods and Procedures: We performed a cross‐sectional study using data from the 2000 Behavioral Risk Factor Surveillance System, the largest telephone survey of health behaviors in the United States, of age‐adjusted prevalence of obesity, type 2 diabetes, intake of ≥five servings of fruits and vegetables per day, participation in 150 minutes of leisure‐time physical activity per week, receipt of weight management advice, and reports of trying to lose or maintain weight among men and women more than 18 years old. Results: The age‐adjusted prevalence of obesity ranged from 13.1% to 30.0% and that of type 2 diabetes from 3.3% to 9.2%. Among participants who had visited a physician for a routine checkup in the previous 12 months, 13.1% to 27.1% of all participants recalled receiving advice from a health professional about their weight, and 11.7% to 34.6% of overweight or obese participants recalled receiving advice to maintain or lose weight. Discussion: Significant differences in the prevalence of obesity and self‐reported type 2 diabetes and in medical practice patterns regarding weight management advice exist among metropolitan statistical areas. These results suggest important opportunities to investigate reasons for these variations that could potentially be used to mitigate the current epidemic of obesity and to identify areas where obesity and diabetes prevention efforts may need to be targeted.     

Comparison of self-reported and measured BMI as correlates of disease markers in US adults

Objective: The purpose of this study is to evaluate the validity of BMI based on self‐reported data by comparison with technician‐measured BMI and biomarkers of adiposity. Research Methods and Procedures: We analyzed data from 10,639 National Health and Nutrition Education Study III participants ≥20 years of age to compare BMI calculated from self‐reported weight and height with BMI from technician‐measured values and body fatness estimated from bioelectrical impedance analysis in relation to systolic blood pressure, fasting blood levels of glucose, high‐density lipoprotein‐cholesterol, triglycerides, C‐reactive protein, and leptin. Results: BMI based on self‐reported data (25.07 kg/m²) was lower than BMI based on technician measurements (25.52 kg/m²) because of underreporting weight (?0.56 kg; 95% confidence interval, ?0.71, ?0.41) and overreporting height (0.76 cm; 95% confidence interval, 0.64, 0.88). However, the correlations between self‐reported and measured BMI values were very high (0.95 for whites, 0.93 for blacks, and 0.90 for Mexican Americans). In terms of biomarkers, self‐reported and measured BMI values were equally correlated with fasting blood glucose (r = 0.43), high‐density lipoprotein‐cholesterol (r = ?0.53), and systolic blood pressure (r = 0.54). Similar correlations were observed for both measures of BMI with plasma concentrations of triglycerides and leptin. These correlations did not differ appreciably by age, sex, ethnicity, or obesity status. Correlations for percentage body fat estimated through bioelectrical impedance analysis with these biomarkers were similar to those for BMI. Discussion: The accuracy of self‐reported BMI is sufficient for epidemiological studies using disease biomarkers, although inappropriate for precise measures of obesity prevalence.     

Racial/Ethnic Differences in Weight Perception

The objective of this research was to estimate the prevalence of weight misperception among adults using the most recent nationally representative data, according to measured weight category and to assess the relationship between weight misperception and race/ethnicity. Height and weight were measured as part of the 1999–2006 National Health and Nutrition Examination Survey. The study sample consisted of 17,270 adults aged ≥20 years. BMI was categorized as underweight (BMI < 18.5), healthy weight (18.5 ≤ BMI < 25), overweight (25 ≤ BMI < 30), and obese (BMI ≥ 30). Subjects reported self‐perception of weight status. Among study subjects, 31.7% of healthy weight adults, 38.1% of overweight adults, and 8.1% of obese adults incorrectly perceived their weight category. Among obese men, the odds of weight misperception were higher for non‐Hispanic blacks (odds ratio (OR) = 3.0; 95% confidence interval (CI) = 2.0–4.5) compared to non‐Hispanic whites and for persons with less than a high school education (OR = 2.1; 95% CI = 1.3–2.1), compared to those with some college education. Among obese women, the odds of weight misperception were higher for non‐Hispanic blacks (OR = 3.4; 95% CI = 1.4, 3.1) and Mexican Americans (OR = 1.9; 95% CI = 1.2, 3.2) compared to non‐Hispanic whites and for persons with less than high school education compared to those with some college education (OR = 5.5; 95% CI = 3.3–9.3). Weight misperception is highly prevalent in the US population, and more frequent in racial/ethnic minorities, males, and in persons with lower educational levels. Addressing the issue of weight misperception may help address the problem of obesity in the United States by increasing awareness of healthy weight levels, which may subsequently have an impact on weight‐related behavior change.     

Waist Circumference is an Independent Correlate of Errors in Self‐Reported BMI

Although there are issues of reporting bias surrounding the use of self‐reported BMI, it is frequently the method employed to establish the prevalence of obesity. The goal of this study was to assess whether, independently of measured BMI, waist circumference (WC) was associated with the magnitude of the difference between self‐reported and measured BMI within a large sample of European‐American (EA) and African‐American (AA) adults. Self‐reported height and weight, and measured height, weight, and WC were collected on 12,809 adults (61% women, 66% EA) aged 18–65 years. Mean negative BMI differences (self‐reported minus measured BMI) were identified in all race‐by‐sex groups (AA men: ?0.55; EA men: ?0.63; AA women: ?0.91; EA women: ?0.67). WC was negatively associated with the BMI difference such that a higher WC was associated with greater under‐reporting of BMI. However, after adjusting for age and measured BMI, WC was positively associated with the BMI difference in all race‐by‐sex groups. These results suggest that WC could be useful in gaining an insight into people's awareness of their own body size and fatness.     

Adult Obesity and Office‐based Quality of Care in the United States

Nationally representative data on the quality of care for obese patients in US‐ambulatory care settings are limited. We conducted a cross‐sectional analysis of the 2005 and 2006 National Ambulatory Medical Care Survey (NAMCS). We examined obesity screening, diagnosis, and counseling during adult visits and associations with patient and provider characteristics. We also assessed performance on 15 previously published ambulatory quality indicators for obese vs. normal/overweight patients. Nearly 50% (95% confidence interval (CI): 46–54%) of visits lacked complete height and weight data needed to screen for obesity using BMI. Of visits by patients with clinical obesity (BMI ≥30.0 kg/m²), 70% (66–74%) were not diagnosed and 63% (59–68%) received no counseling for diet, exercise, or weight reduction. The percentage of visits not being screened (48%), diagnosed (66%), or counseled (54%) for obesity was also notably higher than expected even for patients with known obesity comorbidities. Performance (defined as the percentage of applicable visits receiving appropriate care) on the quality indicators was suboptimal overall. In particular, performance was no better than 50% for eight quality indicators, which are all related to the prevention and treatment of obesity comorbidities, e.g., coronary artery disease, hypertension, hyperlipidemia, asthma, and depression. Performance did not differ by weight status for any of the 15 quality indicators; however, poorer performance was consistently associated with lack of height and weight measurements. In conclusion, many opportunities are missed for obesity screening and diagnosis, as well as for the prevention and treatment of obesity comorbidities, in office‐based practices across the United States, regardless of patient and provider characteristics.     

The validity of self-reported weight change among adolescents and young adults

Objective: To assess the association of weight change based on serial self‐reported vs. measured weights. Research Methods and Procedures: Two thousand two hundred eighty‐four male and 2476 female participants in the National Longitudinal Study of Adolescent Health who provided information on weight at Waves II and III and were at least 16 years of age were studied. Linear regression was used to assess predictors of the discrepancy between weight change based on self‐reported vs. measured weights. Logistic regression was used to identify predictors of self‐report correctly classifying participants in terms of weight change category. Results: Self‐reported weight was slightly lower than measured weight at Waves II and III, but weight change based on self‐reported weights underestimated true weight change by only 2.1 (female participants) to 2.8 (male participants) pounds. Overweight and obese female participants were consistent in their under‐reporting of their weight more than their leaner peers; thus, the discrepancy between weight change from Wave II to Wave III based on serial self‐reports vs. measured weights was significantly smaller among the obese female vs. healthy‐weight female participants (0.3‐ vs. 2.3‐pound underestimation, p < 0.05). Among the male participants, the same pattern was evident. African‐American ethnicity, Hispanic ethnicity, the level of physical activity, the hours per week watching television, and weight change efforts were not related to the discrepancy between weight change based on self‐reported vs. measured weights. Discussion: The discrepancy between weight change based on self‐report vs. measured weights was minor and not related to race, weight change efforts, activity, or inactivity, thus suggesting that much of the error is random.     

Varying Body Mass Index Cutoff Points to Describe Overweight Prevalence Among U. S. Adults: NHANES III (1988 to 1994)

KUCZMARSKI, ROBERT J, MARGARET D CARROLL, KATHERINE M FLEGAL, RICHARD P TROIANO. Varying body mass index cutoff points to determine overweight prevalence among U. S. adults: NHANES III (1988 to 1994). Body mass index (BMI; kg/m²) distributions are commonly reported in the scientific literature to describe weight for stature. These data are collected for various groups of subjects in local health and body composition studies, and comparisons with national distributions are often desirable. Tabular data for population prevalence estimates from thethird National Health and Nutrition Examination Survey (NHANES III, 1988 to 1994) at selected gender- and age-specific BMI levels ranging from <18. 0 to >45. 0 are presented and compared with various examples of BMI criteria reported in the scientific literature. NHANE HI was a statistically representative national probability sample of the civilian, noninstitutionalized population of the United States in which height and weight were measured as part of a more comprehensive health examination. The implications of varying population prevalence estimates based on varying BMI cutoff points are briefly discussed for selected examples including World Health Organization overweight/obesity criteria and the U. S. Dietary Guidelines for Americans. The median BMI for U. S. adults aged 20 years and older is 25. 5 kg/m². Median stature and weight for men are 175. 5 cm and 80. 0 kg and for women are 161. 6 cm and 65. 6 kg, respectively. The percentage of the population with BMI <19. 0 is 1. 6% for men, 5. 7% for women; BMI 19. 0 to <25. 0 is 39. 0% for men, 43. 6% for women; BMI 25. 0 is 59. 4% for men, 50. 7% for women. An estimated 97. 1 million adults have a BMI 25. 0. Additional prevalence estimates based on other BMI cutoff points and ages are presented.     

Does Clinical Depression Affect the Accuracy of Self‐reported Height and Weight in Obese Women?

Objective: Recent research from a self‐report survey showed a strong association between obesity and clinical depression in women. The present analysis assessed whether differential bias in self‐reports of height and weight as a function of depression influences the apparent strength of the association. Methods: Accuracy of self‐reported height and weight was assessed in 250 obese (mean BMI=38.7 kg/m²) women, 135 of whom met the American Psychiatric Association DSM‐IV diagnostic criteria for clinical depression. Results: Depressed and non‐depressed women underreported their weight by 1.5 and 1.2 kg, respectively. They underreported their height by 0.002 and 0.003 m, respectively. Discussion: Bias in self‐reports of body weight and height is similar in depressed and non‐depressed obese women. The underreporting of weight in both groups is similar in magnitude to that seen in normal weight women. Thus, using self‐reports of height and weight seems unlikely to bias estimates of the association between obesity and clinical depression in women.     

The Longitudinal Association From Obesity to Depression: Results From the 12‐year National Population Health Survey

Prior observational studies have investigated the association between obesity and depression but evidence remains weak and mixed. There has been a call for high‐quality longitudinal studies to elucidate the etiologic relationship from obesity to depression. The main objective of this study was therefore to investigate whether obesity was a risk factor for depression in a nationally representative sample followed for 12 years. Seven waves of data collection (1994–1995 to 2006–2007) were obtained from the National Population Health Survey (NPHS). Our analyses included 10,545 adults without depression at baseline. Past‐year major depression episode (MDE) was assessed from the Composite International Diagnostic Interview‐Short Form for Major Depression (CIDI‐SFMD). Obesity was estimated using baseline BMI from self‐reported weight and height (obesity: BMI ≥30 kg/m²). Kaplan–Meier survival curves were generated and Cox proportional hazard regression modeling was used to estimate the risk of MDE by obesity status, controlling for sociodemographic and health and lifestyle variables. We found that obesity at baseline did not significantly predict subsequent MDE in women (adjusted hazard ratio (AHR): 1.03, 95% confidence interval (CI) 0.84–1.26) and negatively predicted MDE in men (HR: 0.71, CI 0.51–0.98), after adjusting for important confounders. In summary, our findings suggest that obesity is a significant (negative) predictor of depression in adult men but not in women. These results moderate prior evidence supporting a positive link from obesity to depression.