Nutritional Inadequacy: Unraveling the Methodological Challenges for the Application of the Probability Approach or the EAR Cut-Point Method—A Pregnancy Perspective

The aim of this study was to unravel the methodological challenges when exploring nutritional inadequacy, involving 608 healthy pregnant women. The usual intake of twenty-one nutrients was recorded by employing a validated FFQ. Simulated datasets of usual intake were generated, with randomly imposed uncertainty. The comparison between the usual intake and the EAR was accomplished with the probability approach and the EAR cut-point method. Point estimates were accompanied by bootstrap confidence intervals. Bootstrap intervals applied on the risk of inadequacy for raw and simulated data tended in most cases to overlap. A detailed statistical analysis, aiming to predict the level of inadequacy, as well as the application of the EAR cut-point method, along with bootstrap intervals, could effectively be used to assess nutrient inadequacy. However, the final decision for the method used depends on the distribution of nutrient-intake under evaluation. Irrespective of the applied methodology, moderate to high levels of inadequacy, calculated from FFQ were identified for certain nutrients (e.g. vitamins C, B6, magnesium, vitamin A), while the highest were recorded for folate and iron. Considering that micronutrient-poor, obesogenic diets are becoming more common, the underlying rationale may help towards unraveling the complexity characterizing nutritional inadequacies, especially in vulnerable populations.

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The use of external within-person variance estimates to adjust nutrient intake distributions over time and across populations

Public Health Nutrition ◽

10.1079/phn2004671 ◽

2005 ◽

Vol 8 (1) ◽

pp. 69-76 ◽

Cited By ~ 9

Author(s):

Lisa Jahns ◽

Lenore Arab ◽

Alicia Carriquiry ◽

Barry M Popkin

Keyword(s):

Nutrient Intake ◽

Point Method ◽

Prevalence Estimate ◽

State University ◽

Cut Point ◽

Statistical Adjustment ◽

Prevalence Estimates ◽

Usual Intake ◽

24 Hour Recall ◽

Variance Estimates

AbstractObjective:To examine the utility of using external estimates of within-person variation to adjust usual nutrient intake distributions.Design:Analyses of the prevalence of inadequate intake of an example nutrient by the Estimated Average Requirement (EAR) cut-point method using three different methods of statistical adjustment of the usual intake distribution of a single 24-hour recall in Russian children in 1996, using the Iowa State University method for adjustment of the distribution. First, adjusting the usual intake distribution with day 2 recalls from the same 1996 sample (the correct method) second, adjusting the distribution using external variance estimates derived from US children in 1996; and third, adjusting the distribution using external estimates derived from Russian children of the same age in 2000. We also present prevalence estimates based on naïve statistical analysis of the unadjusted distribution of intakes.Setting/subjects:Children drawn from the Russia Longitudinal Monitoring Survey in 1996 and 2000 and from the 1996 Continuing Survey of Food Intakes by Individuals.Results:When the EAR cut-point method is applied to a single recall, the resulting prevalence estimate in this study is inflated by 100–1300%. When the intake distribution is adjusted using an external variance estimate, the prevalence estimate is much less biased, suggesting that any adjustment may give less biased estimates than no adjustment.Conclusions:In moderately large samples, adjusting distributions with external estimates of variances results in more reliable prevalence estimates than using 1–day data.

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A Monte Carlo simulation to validate the EAR cut-point method for assessing the prevalence of nutrient inadequacy at the population level

Public Health Nutrition ◽

10.1079/phn2004616 ◽

2004 ◽

Vol 7 (7) ◽

pp. 893-900 ◽

Cited By ~ 34

Author(s):

B de Lauzon ◽

JL Volatier ◽

A Martin

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Population Level ◽

Point Method ◽

Probabilistic Methods ◽

Recommended Dietary Allowance ◽

The Real ◽

Cut Point ◽

Probability Approach ◽

Dietary Allowance

AbstractObjective:The aim of this study was to validate the EAR cut-point method for assessing the prevalence of nutrient inadequacy at the population level.Design and subjects:Different methods for estimating the prevalence of inadequate intake were compared: the cut-off point method, with cut-off points at the Recommended Dietary Allowance (RDA), 0.66 RDA, 0.50 RDA and the Estimated Average Requirement (EAR); the probability approach; and a Monte Carlo simulation. In total, 591 men and 674 women, aged 20–55 years, were included in the analyses.Results:The prevalence of inadequate intake as estimated by the EAR cut-point method was similar to the prevalence of inadequacy estimated by both probabilistic methods. The cut-point method with RDA, 0.66 RDA and 0.50 RDA as cut-off limits induced an over- or an underestimation of the real prevalence of inadequacy.Conclusions:Probabilistic methods consider both the intake variability and the requirement variability, and, as a result, their estimation should be closer to the real prevalence of inadequacy. The use of the EAR cut-point method yields a good estimation of the prevalence of inadequate intake, comparable to the probability approach, and limits over- and underestimation of the prevalence induced by other cut-off points.

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Prevalence of iodine inadequacy in Switzerland assessed by the estimated average requirement cut-point method in relation to the impact of iodized salt

Public Health Nutrition ◽

10.1017/s1368980014002018 ◽

2014 ◽

Vol 18 (8) ◽

pp. 1333-1342 ◽

Cited By ~ 18

Author(s):

Max Haldimann ◽

Murielle Bochud ◽

Michel Burnier ◽

Fred Paccaud ◽

Vincent Dudler

Keyword(s):

General Population ◽

Iodine Intake ◽

Point Method ◽

Iodized Salt ◽

Target Range ◽

Female Population ◽

Population Groups ◽

Cut Point ◽

Iodine Supply ◽

The Impact

AbstractObjectiveTo assess the iodine status of Swiss population groups and to evaluate the influence of iodized salt as a vector for iodine fortification.DesignThe relationship between 24 h urinary iodine and Na excretions was assessed in the general population after correcting for confounders. Single-day intakes were estimated assuming that 92 % of dietary iodine was excreted in 24 h urine. Usual intake distributions were derived for male and female population groups after adjustment for within-subject variability. The estimated average requirement (EAR) cut-point method was applied as guidance to assess the inadequacy of the iodine supply.SettingPublic health strategies to reduce the dietary salt intake in the general population may affect its iodine supply.SubjectsThe study population (1481 volunteers, aged ≥15 years) was randomly selected from three different linguistic regions of Switzerland.ResultsThe 24 h urine samples from 1420 participants were determined to be properly collected. Mean iodine intakes obtained for men (n705) and women (n715) were 179 (sd68·1) µg/d and 138 (sd57·8) µg/d, respectively. Urinary Na and Ca, and BMI were significantly and positively associated with higher iodine intake, as were men and non-smokers. Fifty-four per cent of the total iodine intake originated from iodized salt. The prevalence of inadequate iodine intake as estimated by the EAR cut-point method was 2 % for men and 14 % for women.ConclusionsThe estimated prevalence of inadequate iodine intake was within the optimal target range of 2–3 % for men, but not for women.

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Translating The Moderate-to-vigorous Physical Activity Recommendation To Steps Per Day: Influence Of The Cut-point Method

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000678476.64397.1b ◽

2020 ◽

Vol 52 (7S) ◽

pp. 424-424

Author(s):

Maribel Parra-Saldias ◽

Daniel Mayorga-Vega ◽

Jesús Viciana ◽

Farah Ramírez-Marrero

Keyword(s):

Physical Activity ◽

Vigorous Physical Activity ◽

Point Method ◽

Physical Activity Recommendation ◽

Cut Point ◽

Steps Per Day

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Defining an Optimal Cut-Point Value in ROC Analysis: An Alternative Approach

Computational and Mathematical Methods in Medicine ◽

10.1155/2017/3762651 ◽

2017 ◽

Vol 2017 ◽

pp. 1-14 ◽

Cited By ~ 113

Author(s):

Ilker Unal

Keyword(s):

Diagnostic Accuracy ◽

Sensitivity And Specificity ◽

Roc Curve ◽

Simulated Data ◽

Real Data ◽

Roc Curve Analysis ◽

New Approach ◽

Cut Point ◽

Alternative Approach ◽

The Difference

ROC curve analysis is often applied to measure the diagnostic accuracy of a biomarker. The analysis results in two gains: diagnostic accuracy of the biomarker and the optimal cut-point value. There are many methods proposed in the literature to obtain the optimal cut-point value. In this study, a new approach, alternative to these methods, is proposed. The proposed approach is based on the value of the area under the ROC curve. This method defines the optimal cut-point value as the value whose sensitivity and specificity are the closest to the value of the area under the ROC curve and the absolute value of the difference between the sensitivity and specificity values is minimum. This approach is very practical. In this study, the results of the proposed method are compared with those of the standard approaches, by using simulated data with different distribution and homogeneity conditions as well as a real data. According to the simulation results, the use of the proposed method is advised for finding the true cut-point.

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Comparison of 3 Accelerometer Data Reduction Approaches, Step Counts, and 2 Self-Report Measures for Estimating Physical Activity in Free-Living Adults

Journal of Physical Activity and Health ◽

10.1123/jpah.10.7.1068 ◽

2013 ◽

Vol 10 (7) ◽

pp. 1068-1074 ◽

Cited By ~ 11

Author(s):

M. Renée Umstattd Meyer ◽

Stephanie L. Baller ◽

Shawn M. Mitchell ◽

Stewart G. Trost

Keyword(s):

Physical Activity ◽

Regression Model ◽

Data Reduction ◽

Research Area ◽

Point Method ◽

Self Report ◽

Accelerometer Data ◽

Free Living ◽

Cut Point ◽

Important Research Area

Background:Accelerometers have become one of the most common methods of measuring physical activity (PA). Thus, validity of accelerometer data reduction approaches remains an important research area. Yet, few studies directly compare data reduction approaches and other PA measures in free-living samples.Objective:To compare PA estimates provided by 3 accelerometer data reduction approaches, steps, and 2 self-reported estimates: Crouter’s 2-regression model, Crouter’s refined 2-regression model, the weighted cut-point method adopted in the National Health and Nutrition Examination Survey (NHANES; 2003–2004 and 2005–2006 cycles), steps, IPAQ, and 7-day PA recall.Methods:A worksite sample (N = 87) completed online-surveys and wore ActiGraph GT1M accelerometers and pedometers (SW-200) during waking hours for 7 consecutive days. Daily time spent in sedentary, light, moderate, and vigorous intensity activity and percentage of participants meeting PA recommendations were calculated and compared.Results:Crouter’s 2-regression (161.8 ± 52.3 minutes/day) and refined 2-regression (137.6 ± 40.3 minutes/day) models provided significantly higher estimates of moderate and vigorous PA and proportions of those meeting PA recommendations (91% and 92%, respectively) as compared with the NHANES weighted cut-point method (39.5 ± 20.2 minutes/day, 18%). Differences between other measures were also significant.Conclusions:When comparing 3 accelerometer cut-point methods, steps, and self-report measures, estimates of PA participation vary substantially.

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Use of day and night urinary iodine excretion to estimate the prevalence of inadequate iodine intakes via the estimated average requirement cut-point method

Swiss Medical Weekly ◽

10.4414/smw.2019.20090 ◽

2019 ◽

Author(s):

Elizabeth Stalder ◽

Max Haldimann ◽

Annabelle Blanc ◽

Vincent Dudler ◽

Belen Ponte ◽

...

Keyword(s):

Urinary Iodine ◽

Point Method ◽

Urinary Iodine Excretion ◽

Cut Point ◽

Iodine Excretion

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Scanning Electron Microscopy of Dried and Acid Treated Shells of Difflugia

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007268x ◽

1973 ◽

Vol 31 ◽

pp. 448-449

Author(s):

Barry S. Eckert ◽

S. M. McGee-Russell

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Critical Point ◽

Point Method ◽

External Structure ◽

Cell Locomotion ◽

Single Opening ◽

Scanning Electron

Difflugia lobostoma is a shelled amoeba. The shell is an external structure of considerable mass which presents the animal with special restrictions in cell locomotion which are met by the development of active pseudopodial lobopodia containing, apparently, an organized system of thick and thin microfilaments (Eckert and McGee-Russell, 1972). The shell is constructed of sand grains picked up from the environment, and cemented into place with a secretion. There is a single opening through which lobopods extend. The organization of the shell was studied by scanning electron microscopy (SEM).Intact shells or animals with shells were dried by the critical point method of Anderson (1966) or air dried, after primary fixation in glutaraldehyde.

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