Accuracy of self-reported height, weight and waist circumference in a Japanese sample

Moderators and mediators of the association between the obesogenicity of neighbourhoods and weight status in Dutch adults

This study aimed to assess sociodemographic, personality, and psychological moderators, and lifestyle behavioural mediators, of the association between obesogenicity of neighbourhoods and weight status in Dutch adults. This cross-sectional study used baseline data of 150,506 adult participants of the Lifelines study. To quantify obesogenicity of Dutch neighbourhoods, the Obesogenic Built Environment CharacterisTics (OBCT) index was used, calculated for 1000 m circular buffers around participant's residencies. Z-scores of components across food and physical activity (PA) environments were averaged, and rescaled from 0 to 100. Weight status was operationalised as objectively measured waist circumference. Stratified linear regression analyses by (self-reported) sociodemographic factors, perceived stress, impulsivity, self-discipline, and deliberation were conducted when interaction terms were significant (P < .01). Mediation by adherence to the Dutch PA guidelines and dietary behaviour was examined using the difference-in-coefficients approach. Every 10% increase in OBCT index was associated with a 0.65 (P < .001, 95%CI [0.59, 0.71]) centimetre larger waist circumference. The association was largest for respondents who were younger, had the lowest income, the highest educational level, the least self-discipline, the highest impulsivity scores and the most perceived stress. Adherence to PA guidelines and dietary behaviour mediated 13.3% of this association; however, the difference in coefficients was not statistically significant. Our findings enable to better target lifestyle interventions to individuals most vulnerable to obesogenic environments. Furthermore, they provide guidance for policymakers and urban planners in promoting health-enhancing environments.

Breaking Academic Silos: Pedagogical Recommendations for Equitable Obesity Prevention Training and Research During an Age of Nutrition Polarization

Introduction

Obesity is a preventable chronic condition and a risk factor for poor health and early mortality. Weight stigma and weight-neutral medicine are popular topics in social media that are often at odds with current medical guidelines on obesity treatment and prevention. This conflict may erode the public's trust in science, impede research progress on preventing obesity in marginalized groups, and uphold the ongoing and historical lack of diversity among nutrition trainees.

Methods

The authors conducted a series of student-led dialogue sessions with nutrition graduate students in Boston, Massachusetts, from March to May 2023 to understand perceptions of obesity research, health equity, and racism and discrimination. This article summarizes the lessons learned and provides pedagogical recommendations for jointly addressing obesity at the population level and the recruitment, training, and retention of diverse scholars, clinicians, and public health practitioners.

Results

Dialogue sessions revealed that students perceive a disproportionate focus on the harms of obesity as a chronic disease, highlighting that inadequate attention is given to weight stigma and discrimination. Some participants believed that weight-based discrimination is equally detrimental to individual health and wellbeing as having obesity. Discussions also emphasized the need to pinpoint the multidimensional and cultural manifestations of weight stigma, which necessitates collaboration across social sectors and academic disciplines. Students recognized the urgent need to apply an equity lens to obesity research and teaching but felt limited in their access to experts within nutrition science who specialize in racism, discrimination, eating disorders, and weight stigma.

Conclusions

This study identified concrete opportunities for urgently needed new training and research in population-level obesity prevention, emphasizing antiracism, harm reduction, and elimination of stigma and bias across multiple levels of science and society. Overall, the decision to use the BMI within pedagogy and training must be explicitly stated-research, population surveillance, decision-making, or treatment pedagogy and training-while acknowledging its strengths and limitations across diverse settings. Finally, the social determinants of obesity should incorporate not only weight stigma but also racism and multiple forms of discrimination.

Reliability and validity of the Japanese version of the Pregnancy and Weight Gain Attitude Scale

This study aimed to develop the Japanese version of the Pregnancy and Weight Gain Attitude Scale (J-PWGAS) as a measurement of body image regarding body weight and shape during pregnancy. This cross-sectional study was conducted at a perinatal medical center in Osaka, Japan, between March and November 2020. We recruited pregnant women in their second or third trimester, who were 20 years old or older and without pregnancy complications. This study evaluated the criterion validity, construct validity, internal consistency, and test-retest reliability. Of the participants, 218 and 102 women participated in the validation and test-retest reliability studies, respectively. An exploratory factor analysis revealed a 17-item, five-factor structure. The J-PWGAS indicated acceptable criterion validity, internal consistency, and test-retest reliability. The J-PWGAS can measure attitudes toward gestational weight gain in Japanese pregnant women and would be useful in examining the association of body image with weight gain and psychological status during pregnancy.

Association Between Body Image Before and During Pregnancy and Gestational Weight Gain in Japanese Women: A Prospective Cohort Study

OBJECTIVES

More than half of women do not achieve appropriate gestational weight gain. Maternal body image may be an important factor associated with gestational weight gain. However, this association has not been thoroughly evaluated. We aimed to elucidate whether body image parameters before and during pregnancy are associated with gestational weight gain in Japanese women.

METHODS

This prospective cohort study was conducted at a hospital in Osaka, Japan from March 2020 to March 2021. We recruited women with singleton pregnancies in their second and third trimesters. Body image was assessed using the Pregnancy and Weight Gain Attitude Scale and additional questions. Gestational weight gain was classified as insufficient, appropriate, or excessive based on recommended ranges in Japan. One-way analysis of variance, chi-square tests, and multinomial logistic regression analyses were performed to identify factors associated with insufficient or excessive weight gain.

RESULTS

Of 266 enrolled women, 47 had insufficient weight gain and 100 had excessive weight gain during pregnancy. Risk factors for excessive gestational weight gain included a history of dietary restriction before pregnancy, negative attitudes toward gestational weight gain, and perception of body shape as fat and body shape dissatisfaction during pregnancy. Perception of body shape as thin during pregnancy was identified as a risk factor for insufficient gestational weight gain.

CONCLUSIONS

Body image before and during pregnancy may be an important factor in preventing insufficient or excessive gestational weight gain in Japanese women. Healthcare professionals should consider body image when providing health guidance on weight management to pregnant women.

Selecting, optimizing and externally validating a preexisting machine-learning regression algorithm for estimating waist circumference

Obesity, typically defined by the body mass index (BMI), has well known negative health effects. However, the BMI has serious deficiencies in predicting the adverse risks associated to obesity. Waist circumference (WC) is an alternative to define obesity and a better disease predictor according to the literature. However, old databases often lack this information, it is inaccurate (collected via self-report) or it is incomplete. Thus, this study accurately assesses WC using machine learning. The novel approaches are: 1) predictor variables (weight, height, age and sex) likely to appear in most data sets are used. 2) Publicly available data (including non-adults) and algorithms are used. 3) Systematic methods for data cleanup, model selection, hyperparameter optimization and external validation are performed. DATA ARE CLEANED: one variable per column, no special codes, missing values or outliers. Preexisting regression algorithms are gaged by cross-validation, using one data set. The hyperparameters of the best performing algorithm are optimized. The tuned algorithm is externally validated with other data sets by cross-validation. In spite of the limited number of features, the tuned algorithm outperforms prior WC approximations, using the same or similar predictor variables. The tuned algorithm enables using data where WC is not measured, is incomplete or is unreliable. A similar approach would be useful to estimate other variables of interest.

Mindfulness, mental health, and motives for eating tasty foods when not in metabolic need

Habitual consumption of highly palatable foods when not in metabolic need (HPF eating) is linked to obesity. High HPF consumption is also linked to mental health disorder (MHD) symptoms. Mindfulness-based interventions are popular treatments for obesity and MHDs, but little is known about the relationship between trait mindfulness and motive-based HPF eating. Therefore, a total of 927 young adults completed a survey that included the Palatable Eating Motives Scale-7 (which identifies Coping-, Reward enhancement-, Social-, and Conformity-eating), the Mindful Attention Awareness Scale, the Perceived Stress Scale, and demographic and body mass index (BMI) questions. An MHD questionnaire allowed a comparison of HPF eating between participants with and without various MHDs. Regressions revealed that Coping-eating was independently associated with lower mindfulness and also greater perceived stress, higher BMI, and female sex. Of these variables, only lower mindfulness was independently associated with Reward-, Social-, and Conformity-eating. Coping- and Reward-eating were more frequent in participants with versus without an anxiety disorder, depression, ADD/ADHD, and PTSD. Coping-eating was also more frequent in participants with body dysmorphic disorder. These findings warrant investigations in participants with clinically validated diagnoses for DSM-specific MHDs. Results from such investigations and the uncovered nature of associations between motive-specific HPF eating and trait mindfulness could provide novel targets to improve mindfulness-based interventions for obesity and MHDs.

Association between prepregnancy weight change and risk of gestational diabetes mellitus in Chinese pregnant women

BACKGROUND

Evidence regarding prepregnancy weight change and gestational diabetes mellitus (GDM) is lacking among East Asian women.

OBJECTIVE

Our study aimed to investigate the association between weight change from age 18 years to pregnancy and GDM in Chinese pregnant women.

METHODS

Our analyses included 6972 pregnant women from the Tongji-Shuangliu Birth Cohort. Body weights were recalled for age 18 years and the time point immediately before pregnancy, while height was measured during early pregnancy. Prepregnancy weight change was calculated as the difference between weight immediately before pregnancy and weight at age 18 years. GDM outcomes were ascertained by 75-g oral glucose tolerance test. Multivariable logistic regression models were used to estimate the association between prepregnancy weight change and risk of GDM.

RESULTS

501 (7.2%) developed GDM in the cohort. After multivariable adjustments, prepregnancy weight change was linearly associated with a higher risk of incident GDM (P < 0.001). Compared with participants with stable weight (weight change within 5.0 kg) before pregnancy, multivariable-adjusted odds ratios and 95% confidence intervals were 1.55 (1.22, 1.98) and 2.24 (1.78, 2.83) for participants with moderate (weight gain of 5-9.9 kg) and high (weight gain ≥ 10 kg) weight gain, respectively. In addition, overweight/obesity immediately before pregnancy mediated 17.6% and 31.7% of the associations of moderate and high weight gain with GDM risk, while weekly weight gain during pregnancy mediated 21.1% and 22.7% of the associations.

CONCLUSIONS

Weight gain from age 18 years to pregnancy was significantly associated with a higher risk of GDM. Maintaining weight stability, especially prevention of excessive weight gain from early adulthood to pregnancy could be a potential strategy to reduce GDM risk.

Association between maternal multimorbidity and preterm birth, low birth weight and small for gestational age: a prospective birth cohort study from the Japan Environment and Children's Study

OBJECTIVES

Multimorbidity is defined as the coexistence of two or more chronic physical or psychological conditions within an individual. The association between maternal multimorbidity and adverse perinatal outcomes such as preterm delivery and low birth weight has not been well studied. Therefore, this study aimed to investigate this association.

METHODS

We conducted a prospective cohort study using data from the Japan Environment and Children's Study of pregnant women between 2011 and 2014. Those with data on chronic maternal conditions were included in the study and categorised as having no chronic condition, one chronic condition or multimorbidities. The primary outcomes were the incidence of preterm birth (PTB), low birth weight (LBW) and small for gestational age (SGA). Adjusted logistic regression was performed to estimate ORs (aORs) and 95% CIs.

RESULTS

Of the 104 062 fetal records, 86 885 singleton pregnant women were analysed. The median maternal age and body mass index were 31 years and 20.5 kg/m², respectively. The prevalence of pregnant women with one or more chronic conditions was 40.2%. The prevalence of maternal multimorbidity was 6.3%, and that of PTB, LBW, and SGA were 4.6%, 8.1%, and 7.5%, respectively. Pre-pregnancy underweight women were the most common, observed in 15.6% of multimorbidity cases, followed by domestic violence from intimate partner in 13.0%. Maternal multimorbidity was significantly associated with PTB (aOR 1.50; 95% CI 1.33-1.69), LBW (aOR 1.49; 95% CI 1.35-1.63) and SGA (aOR 1.33; 95% CI 1.20-1.46).

CONCLUSION

Maternal multimorbidity was associated with adverse perinatal outcomes, including PTB, LBW and SGA. The risk of adverse perinatal outcomes tends to increase with a rise in the number of chronic maternal conditions. Multimorbidity becomes more prevalent among pregnant women, making our findings important for preconception counselling.

How prepartum appearance-related attitudes influence body image and weight-control behaviors of pregnant Japanese women across pregnancy: Latent growth curve modeling analyses

A thin female physique is idealized in modernized societies, leading many pregnant women to experience body dissatisfaction and avoid weight gain, as pregnancy directs their body away from the sociocultural ideal of thinness. However, not all pregnant women report body dissatisfaction and/or weight-control behavior. We aimed to discern how prepartum weight-related attitudes-thin-ideal internalization, drive for thinness, and appearance comparison tendency-influence changes in negative attitudes toward a pregnant body, body image, and weight-control behavior across pregnancy. Data were longitudinally collected from 208 Japanese pregnant women (Mage = 27.0, SD = 1.74) across three pregnancy periods. Results indicated that overall, negative attitudes toward appearance change during pregnancy, weight-control behaviors, and restrained eating significantly changed across pregnancy. Moreover, those with higher prepartum thin-ideal internalization showed greater decreases in negative attitudes toward appearance change during pregnancy and greater increases in body dissatisfaction, whereas those with higher prepartum drive for thinness and appearance comparison tendency showed greater decreases in restrained eating across pregnancy. Our findings suggest that pregnant women with certain prepartum weight-related attitudes may experience an aggravation of body dissatisfaction while following dietary regimen during pregnancy. Thus, prevention programs may selectively help them reduce their negative body image during pregnancy.

The Association Between Adult Height and Stroke Incidence in Japanese Men and Women: A Population-based Case-Control Study

BACKGROUND

No studies have examined the associations between adult height and ischemic stroke subtypes.

METHODS

We conducted a population-based case-control study that included 2,451 thrombotic and 687 embolic stroke cases, as well as 1,623 intracerebral and 768 subarachnoid hemorrhage cases without history of stroke aged 40-79 years, and the same number of sex- and age-matched controls. Cases and controls were grouped according to the quintile cut-off values of height in controls, and the third quintile, which was approximately the average height group, was used as the reference group. Height divided by one standard deviation of height in controls was also examined as a continuous variable. The analyses were carried out separately for participants aged 40-59 years and 60-79 years.

RESULTS

In both younger and older men, height was linearly inversely associated with total and thrombotic strokes, and the shortest quintile compared to the reference group was associated with increased risks of these strokes. Although height was linearly inversely associated with embolic stroke and intracerebral hemorrhage in younger men, the shortest quintile did not show increased risks of these strokes. Height did not seem to be associated with total stroke and any stroke subtypes in younger women. In contrast, the tallest quintile was significantly associated with increased risks of total stroke and intracerebral hemorrhage, and height tended to be positively associated with these strokes in older women.

CONCLUSION

We reported the associations between adult height and ischemic stroke subtypes for the first time, which differed according to sex and age group.

Measurement accuracy and reliability of self-reported versus measured weight and height among adults in Malaysia: Findings from a nationwide blood pressure screening programme

Most studies reporting prevalence of obesity use actual weight and height measurements. Self-reported weight and height have been used in epidemiological studies as they have been shown to be reliable, convenient, and inexpensive alternatives to actual measurements. However, the accuracy of self-reported weight and height might vary in different regions because of the difference in health awareness and social influences. This study aims to determine the accuracy and reliability of self-reported weight and height compared to actual measured weight and height among adults in Malaysia. This was a cross-sectional study conducted at the community level during blood pressure screening campaigns. Participants self-reported their weight and height in a questionnaire survey. Their weight and height were validated using measurements by researchers on the same setting. Body mass index (BMI) was defined as underweight (<18.5kg/m2), normal (18.5-22.9 kg/m2), overweight (23-27.4 kg/m2) and obesity (≥27.5 kg/m2). Bland-Altman analysis, intraclass correlation coefficients and weighted Kappa statistics were used to assess the degree of agreement between self-reported and measured weight and height. A total of 2781 participants were recruited in this study. The difference between the mean self-reported and measured weight and height were 0.4 kg and 0.4 cm respectively. Weighted Kappa statistics analysis showed that there was a substantial agreement between the BMI classifications derived from self-reported and actual measurement (ҡ = 0.920, p<0.001). There was no marked difference in the sensitivity and specificity of self-reported BMI among Malaysian adults by gender. We observed substantial agreement between self-reported and measured body weight and height within a sample of Malaysian adults. While self-reported body weight showed weaker agreement with actual measurements particularly for obese and overweight individuals, BMI values derived from self-reported weight and height were accurate for 88.53% of the participants. We thus conclude that self-reported height and weight measures may be useful for tracking and estimating population trends amongst Malaysian adults.

Weight over-reporting is associated with low muscle mass among community-dwelling Japanese adults aged 40 years and older: a cross sectional study

Background

Weight misperception adversely affects health-related quality of life (HRQol); however, few studies have evaluated the relationship between weight misperception and muscle mass. This study aimed to examine the relationship of weight misperception with low muscle mass using skeletal muscle index (SMI) estimated by multifrequency bioelectrical impedance analysis (MF-BIA) among community-dwelling Japanese.

Methods

Participants were 525 Japanese individuals aged 40–91 years old (male 89, female 436). Misperception was calculated by subtracting measured value from self-reported weight, presented as a percentage and categorized into tertiles based on sex (under-reporters, acceptable reporters, and over-reporters). Appendicular lean mass was estimated using MF-BIA, and low muscle mass was defined using SMI values of 7.0 and 5.7 kg/m2 for males and females, respectively, based on the Asian Working Group for Sarcopenia 2019 consensus. We evaluated the association between prevalence of low muscle mass and weight misperception (under-reporters and over-reporters) using multivariate logistic regression including covariate.

Results

In total, 9.3% (49/525) of participants had low muscle mass. After adjusting for covariates, prevalence of low muscle mass was higher among over-reporters than acceptable-reporters (odds ratio [OR]; 2.37, 95% confidence interval [CI]; 1.03–5.44). Additionally, sensitivity analysis was performed on females, which confirmed that the prevalence of low muscle mass was higher in over-reporters than in acceptable-reporters (OR, 3.27; 95% CI, 1.18–9.12).

Conclusion

Weight misperception was significantly correlated with low muscle mass, especially in over-reporters.

Effects of Individual Dietary Intervention on Nutrient Intake in Postpartum Japanese Women: A Randomized Controlled Trial

No dietary intervention that focuses on the diet quality of postpartum women has been developed in Japan, although most postpartum women experience an insufficient intake of vitamins and minerals. We aimed to examine whether dietary intervention, based on the health belief model, at both 1 and 3 months postpartum affects nutrient intake and food group consumption at 6 months postpartum. A randomized controlled trial was conducted at a university hospital in Tokyo between 2015 and 2016. Healthy women at 1 month postpartum were randomly allocated to either an intervention group (n = 100) or a control group (n = 94). Dietary intervention included dietary assessment, individual feedback, and dietary guidance. The dietary intakes between the two groups were compared using the Mann-Whitney U test. At 6 months postpartum, the energy-adjusted intakes of protein, total dietary fiber, potassium, magnesium, phosphorus, zinc, vitamin B₆, and β-carotene were significantly higher in the intervention group than in the control group. The changes in energy-adjusted intakes of total dietary fiber and iron from 1 month postpartum to 6 months postpartum were significantly different between the two groups. Dietary intervention based on the health belief model improved nutrition at 6 months postpartum, although the impact was limited.

Association of sleep-disordered breathing and alcohol consumption with hypertension among Japanese male bus drivers

There is limited evidence regarding the combined effects of sleep-disordered breathing (SDB) and alcohol consumption on hypertension. The aim of this study was to examine the combined effects of SDB and alcohol consumption on hypertension in Japanese male bus drivers. This cross-sectional study included 2525 Japanese male bus drivers aged 20-65 years. SDB was assessed using a single-channel airflow monitor, which measured the respiratory disturbance index (RDI) during overnight sleep at home. Alcohol consumption (g/day) was assessed by a self-administered questionnaire and calculated per unit of body weight. Hypertension was defined as systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg and/or use of antihypertensive medications. Multiple logistic regression analyses were performed to examine the association of the combined categories of RDI and alcohol consumption with hypertension. The multivariable-adjusted odds ratio (OR) and 95% confidence interval (95% CI) of hypertension for the alcohol consumption ≥1.0 g/day/kg and RDI ≥ 20 events/h group were 2.41 (1.45-4.00) compared with the alcohol consumption <1.0 g/day/kg and RDI < 10 events/h group. Our results suggest that Japanese male bus drivers with both SDB and excessive alcohol consumption are at higher risk of hypertension than those without SDB and excessive alcohol consumption, highlighting the importance of simultaneous management of SDB and excessive alcohol consumption to prevent the development of hypertension among bus drivers.

Waist circumference prediction for epidemiological research using gradient boosted trees

BACKGROUND

Waist circumference is becoming recognized as a useful predictor of health risks in clinical research. However, clinical datasets tend to lack this measurement and self-reported values tend to be inaccurate. Predicting waist circumference from standard physical features could be a viable method for generating this information when it is missing or mitigating the impact of inaccurate self-reports. This study determined the degree to which the XGBoost advanced machine learning algorithm could build models that predict waist circumference from height, weight, calculated Body Mass Index, age, race/ethnicity and sex, whether they perform better than current models based on linear regression, and the relative importance of each feature in this prediction.

METHODS

We trained tree-based models (via XGBoost gradient boosting) and linear models (via regression) to predict waist circumference from height, weight, Body Mass Index, age, race/ethnicity and sex (n = 60,740 participants). We created 10 iterations of each model, each using 90% of the dataset for training and the remaining 10% for testing performance (this group was different for each iteration). We calculated model performance and feature importance as an average across 10 iterations. We then externally validated the ensembled version of the top model.

RESULTS

The XGBoost model predicted waist circumference with a mean bias ± standard deviation of 0.0 ± 0.04 cm and a root mean squared error of 4.7 ± 0.05 cm, with performance varying slightly by sex and race/ethnicity. The XGBoost model showed varying degrees of improvement over linear regression models. The top 3 predictors were Body Mass Index, weight and race (Asian). External validation found that on average this model overestimated waist circumference by 4.65 cm in the United Kingdom population (mainly due to overprediction in females) and underestimated waist circumference by 1.7 cm in the Chinese population. The respective root mean squared errors were 7.7 cm and 7.1 cm.

CONCLUSIONS

XGBoost-based models accurately predict waist circumference from standard physical features. Waist circumference prediction using this approach would be valuable for epidemiological research and beyond.

Association between maternal height and mode of delivery in nulliparous Japanese women

AIM

The primary aim of this study was to examine the association between maternal height and mode of delivery in nulliparous Japanese women. The secondary aim was to examine the association between maternal height and maternal and neonatal morbidities.

METHODS

This retrospective cohort study included women who gave birth at Osaka Women's and Children's Hospital, a tertiary perinatal center in Japan, from January 2015 to December 2017. Nulliparous Japanese women with singleton gestation, who went into labor at term were included in the study. The primary outcome was mode of delivery, and the secondary outcomes were maternal and neonatal morbidities. The relationships between maternal height and the outcomes were evaluated using multivariate logistic regression analysis adjusted for potential confounders. Maternal height was categorized into five groups with 5-cm increments for the analysis.

RESULTS

A total of 1593 women were analyzed in this study. Shorter women had higher rate of cesarean delivery (CD) than taller women. There were no significant differences in the rates of operative vaginal delivery, maternal morbidity and neonatal morbidity among the maternal-height groups. The adjusted odds ratios (95% confidential interval) of maternal heights of <150 cm, 150-154 cm, 160-164 cm and ≥165 cm for CD, compared with a maternal height of 155-159 cm, were 3.56 (1.79-7.09), 1.68 (1.06-2.64), 0.63 (0.40-1.00) and 0.57 (0.30-1.01), respectively.

CONCLUSION

Shorter nulliparous Japanese women were more likely to undergo intrapartum CD. However, the rates of maternal and neonatal morbidities in shorter women were similar to those in taller women.

Body shape and pants size as surrogate measures of obesity among males in epidemiologic studies

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Alternative anthropometric indicators reflect overall and abdominal obesity in males.

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Abdominal obesity is predicted using age, pants size, Stunkard’s silhouette & weight.

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Stunkard’s silhouette scale reflects well body mass index recently and in the past.

This study aimed at characterizing anthropometric indicators that can be used as alternatives to measurements for assessing overall obesity over adulthood and abdominal obesity among men. We used data from a population-based case-control study of prostate cancer conducted in Montreal, Canada in 2005–2012. It included men aged ≤ 75 years, 1872 of which were newly diagnosed with prostate cancer, and 1918 others randomly selected from the electoral list. In-person interviews elicited reports of height as well as of weight, pants size and Stunkard’s silhouette at 5 time points over adulthood, i.e., for the ages of 20, 40, 50 and 60 years, if applicable, and at the time of interview. Waist and hip circumferences were measured by interviewers following a validated protocol. Analyses were conducted on the overall sample of 3790 subjects, after having confirmed that results did not differ according to disease status. Stunkard’s silhouette scale proved to be an easy-to-administer tool that reflects well reported body mass index, either recently or decades in the past among adult males. It was discriminatory enough to classify individuals according to commonly-used obesity categories. We observed that a model including age, reported pants size, silhouette and weight can reasonably predict current abdominal obesity. In conclusion, alternative anthropometric indicators can serve as valuable means to assess overall and abdominal obesity when measurements cannot be envisaged in the context of epidemiological studies.

Is it time to stop sweeping data cleaning under the carpet? A novel algorithm for outlier management in growth data

All data are prone to error and require data cleaning prior to analysis. An important example is longitudinal growth data, for which there are no universally agreed standard methods for identifying and removing implausible values and many existing methods have limitations that restrict their usage across different domains. A decision-making algorithm that modified or deleted growth measurements based on a combination of pre-defined cut-offs and logic rules was designed. Five data cleaning methods for growth were tested with and without the addition of the algorithm and applied to five different longitudinal growth datasets: four uncleaned canine weight or height datasets and one pre-cleaned human weight dataset with randomly simulated errors. Prior to the addition of the algorithm, data cleaning based on non-linear mixed effects models was the most effective in all datasets and had on average a minimum of 26.00% higher sensitivity and 0.12% higher specificity than other methods. Data cleaning methods using the algorithm had improved data preservation and were capable of correcting simulated errors according to the gold standard; returning a value to its original state prior to error simulation. The algorithm improved the performance of all data cleaning methods and increased the average sensitivity and specificity of the non-linear mixed effects model method by 7.68% and 0.42% respectively. Using non-linear mixed effects models combined with the algorithm to clean data allows individual growth trajectories to vary from the population by using repeated longitudinal measurements, identifies consecutive errors or those within the first data entry, avoids the requirement for a minimum number of data entries, preserves data where possible by correcting errors rather than deleting them and removes duplications intelligently. This algorithm is broadly applicable to data cleaning anthropometric data in different mammalian species and could be adapted for use in a range of other domains.

The Association between Self-Reported Difficulty of Food Access and Nutrient Intake among Middle-Aged and Older Residents in a Rural Area of Japan

We investigated the association of self-reported difficulty of food access, accounting for the perception of food-store accessibility, with nutrient intake among 474 inhabitants (145 men and 329 women) aged ≥40 y in a rural area of Japan. Information on self-reported difficulty of food access and dietary intake was obtained via a self-administrated questionnaire. Analysis of covariance was performed to evaluate the adjusted associations between difficulty of food access and percentages of total energy (i.e., protein, fat, and carbohydrates). Among men, the adjusted means of percent energy from fat in the "difficulty of food access" group (19.2% energy) were significantly lower (by 2.4%) and the percent energy from carbohydrates for this group (57.3% energy) was significantly higher (by 3.3%) than for the "non-difficulty" group. In conclusion, this study found nutritional balance among residents experiencing difficulty of food access results in lower fat and higher carbohydrate intake than for those with non-difficulty of food access among middle-aged and older Japanese men in a rural area.

Accuracy of self-reported height, weight and waist circumference in a Japanese sample

Objective

Inconsistent results have been found in prior studies investigating the accuracy of self‐reported waist circumference, and no study has investigated the validity of self‐reported waist circumference among Japanese individuals. This study used the diagnostic standard of metabolic syndrome to assess the accuracy of individual's self‐reported height, weight and waist circumference in a Japanese sample.

Methods

Study participants included 7,443 Japanese men and women aged 35–79 years. They participated in a cohort study's baseline survey between 2007 and 2011. Participants' height, weight and waist circumference were measured, and their body mass index was calculated. Self‐reported values were collected through a questionnaire before the examination.

Results

Strong correlations between measured and self‐reported values for height, weight and body mass index were detected. The correlation was lowest for waist circumference (men, 0.87; women, 0.73). Men significantly overestimated their waist circumference (mean difference, 0.8 cm), whereas women significantly underestimated theirs (mean difference, 5.1 cm). The sensitivity of self‐reported waist circumference using the cut‐off value of metabolic syndrome was 0.83 for men and 0.57 for women.

Conclusions

Due to systematic and random errors, the accuracy of self‐reported waist circumference was low. Therefore, waist circumference should be measured without relying on self‐reported values, particularly in the case of women.