Andrew W Brown

• PhD
• Professor (Assistant) at Indiana University Bloomington

Randomized controlled trials (RCTs) can produce valid estimates of the benefits and harms of therapeutic interventions. However, incomplete reporting can undermine the validity of their conclusions. Reporting guidelines, such as SPIRIT for protocols and CONSORT for results, have been developed to improve transparency in RCT publications. In this st...

Randomized controlled trials (RCTs) can produce valid estimates of the benefits and harms of therapeutic interventions. However, incomplete reporting can undermine the validity of their conclusions. Reporting guidelines, such as SPIRIT for protocols and CONSORT for results, have been developed to improve transparency in RCT publications. In this st...

Background: One approach to test for differential associations between plant foods with health uses a scoring approach: foods categorized into animal or healthy' plant-based or 'unhealthy' plant-based groups to construct a plant-based diet index (PDI), healthy PDI (hPDI), and unhealthy PDI (uPDI). Objective: To evaluate robustness of associations b...

Caloric restriction (CR) results in reduced energy and protein intake, raising questions about protein restriction’s contribution to CR longevity benefits. We kept ad libitum (AL)–fed male C57BL/6J mice at 27°C (AL27) and pair-fed (PF) mice at 22°C (22(PF27)). The 22(PF27) group was fed to match AL27 while restricted for calories due to cold-induce...

Importance Publishing study protocols might reduce research waste because of unclear methods or incomplete reporting; on the other hand, there might be few additional benefits of publishing protocols for registered trials that are never completed or published. No study has investigated the proportion of published protocols associated with published...

Background Many analytic decisions are made when analyzing an observational dataset, such as how to define an exposure or which covariates to include and how to configure them. Modelling the distribution of results for many analytic decisions may illuminate how instrumental decisions are on conclusions in nutrition epidemiology. Objective We explor...

UNSTRUCTURED In this correspondence, we raise critical issues regarding the article by Arguello et al. (doi:10.2196/43018). In the article by Arguello et al., there is ambiguity regarding whether clustering (potential non-independence of observations within the same office space) and nesting (due to the hierarchical structure of the data) have been...

Background: There is a lack of consensus on a reference range for ionized magnesium (iMg2+) in blood as a measure of status of circulating iMg2+ for screening populations. Objectives: We estimated the reference range of iMg2+ levels for healthy adult populations and the ranges for populations with cardiovascular disease (CVD), type 2 diabetes, hyp...

It is increasingly assumed that there is no one-size-fits-all approach to dietary recommendations for the management and treatment of chronic diseases such as obesity. This phenomenon that not all individuals respond uniformly to a given treatment has become an area of research interest given the rise of personalized and precision medicine. To cond...

Our objective was to convene interdisciplinary experts from government, academia, and industry to develop a Research Roadmap to identify research priorities about processed food intake and risk for obesity and cardiometabolic diseases (CMD) among United States populations. We convened attendees at various career stages with diverse viewpoints in th...

Self-reported nutrition intake (NI) data are prone to reporting bias that may induce bias in estimands in nutrition studies; however, they are used anyway due to high feasibility. We examined whether applying Goldberg cutoffs to remove 'implausible' self-reported NI could reliably reduce bias compared to biomarkers for energy, sodium, potassium, an...

In reading Qiu et al. [...]

Aging is accompanied by increased susceptibility to infections including with viral pathogens resulting in higher morbidity and mortality among the elderly. Significant changes in host metabolism can take place following virus infection. Efficient immune responses are energetically costly, and viruses divert host molecular resources to promote thei...

Interventions for animal lifespan extension like caloric restriction (CR) have identified physiologic and biochemical pathways related to hunger and energy-sensing status as possible contributors, but mechanisms have not been fully elucidated. Prior studies using ghrelin agonists show greater food intake but no effect on lifespan in rodent models....

In a published randomized controlled trial, household units were randomized to a nutrient bar supplementation group or a control condition, but the non-independence of observations within the same household (i.e., the clustering effect) was not accounted for in the statistical analyses. Therefore, we reanalyzed the data appropriately by adjusting d...

Self-reported nutrition intake (NI) data are prone to reporting bias that may induce bias in estimands in nutrition studies; however, they are used anyway due to high feasibility. We examined whether applying Goldberg cutoffs to remove “implausible” self-reported NI could reliably reduce bias compared to biomarkers for energy, sodium, potassium, an...

We read the report by Conner and colleagues that tested whether kiwifruit or vitamin C affected measures of vitality [...]

We were interested to read the report by Halenova et al. [...]

The ASN Board of Directors appointed the Nutrition Research Task Force to develop a report on scientific methods used in nutrition science to advance discovery, interpretation, and application of knowledge in the field. The genesis of this report was growing concern about the tone of discourse among nutrition professionals and the implications of a...

Attendance at professional society meetings facilitates networking, collaboration, and success in academic/scientific fields. Insufficient funds, support, or resources for caregiving can inhibit attendance for parents/caretakers, who may become professionally disadvantaged by not attending professional society conferences. The American Society for...

Objectives Evaluating associations between nutritional exposures and disease outcomes requires numerous analytical decisions. Among these decisions are how nutritional exposures are defined and configured, choices and configuration of covariates, participant exclusion criteria, among others. Each decision potentially affects the results and conclus...

The aim of this study was to compute intra‐class correlations (ICCs) for weight‐related and patient‐reported outcomes in a cluster randomized clinical trial (cRCT) for weight loss. Baseline and follow‐up data from the Promoting Successful Weight Loss in Primary Care in Louisiana (PROPEL) cRCT were used in this analysis. ICCs were computed for basel...

Background Cluster randomized controlled trials (cRCTs) are increasingly used but must be analyzed carefully. We conducted a simulation study to evaluate the validity of a parametric bootstrap (PB) approach with respect to the empirical type I error rate for a cRCT with binary outcomes and a small number of clusters. Methods We simulated a case st...

Traffic light labeling (TLL) of foods is a strategy often included in multicomponent behavioral interventions (MBI) for childhood obesity. TLLs categorize foods as ‘green’ (no restrictions); ‘yellow’ (moderation); and ‘red’ (consume minimally). The body of research investigating the effects of TLL conflates the labeling itself with MBIs that includ...

This review identifies frequent design and analysis errors in aging and senescence research and discusses best practices in study design, statistical methods, analyses, and interpretation. Recommendations are offered for how to avoid these problems. The following issues are addressed: 1) errors in randomization, 2) errors related to testing within-...

To date, nutritional epidemiology has relied heavily on relatively weak methods including simple observational designs and substandard measurements. Despite low internal validity and other sources of bias, claims of causality are made commonly in this literature. Nutritional epidemiology investigations can be improved through greater scientific rig...

Background: Eating or skipping breakfast for weight interests scientific and lay communities. Our objective was to systematically review and meta-analyze causal effects of eating versus skipping breakfast on obesity-related anthropometric outcomes in humans. Methods: Six databases were searched for obesity- and breakfast-related terms (final search...

The UAB Nathan Shock Center focuses on comparative energetics and aging. Energetics, as defined for this purpose, encompasses the causes, mechanisms, and consequences of the acquisition, storage, and use of metabolizable energy. Comparative energetics is the study of metabolic processes at multiple scales and across multiple species as it relates t...

Randomization is an important tool used to establish causal inferences in studies designed to further our understanding of questions related to obesity and nutrition. To take advantage of the inferences afforded by randomization, scientific standards must be upheld during the planning, execution, analysis, and reporting of such studies. We discuss...

Background: Classic nonparametric tests (cNPTs), like Kruskal–Wallis or Mann–Whitney U, are sometimes used to detect differences in central tendency ( i.e. , means or medians). However, when the tests’ assumptions are violated, such as in the presence of unequal variance and other forms of heteroscedasticity, they are no longer valid for testing di...

The use of classic nonparametric tests (cNPTs), such as the Kruskal–Wallis and Mann–Whitney U tests, in the presence of unequal variance for between-group comparisons of means and medians may lead to marked increases in the rate of falsely rejecting null hypotheses and decreases in statistical power. Yet, this practice remains prevalent in the scie...

Abstract Randomized Controlled Trials (RCTs) are the best method to determine causal effects for treatments if they are well done and well reported. Good evidence about proposed treatments for obesity is needed, and Hsieh et al. (Biomed Eng Online 17:149, 2018) are to be commended for putting moxibustion to the test. However, careful evaluation of...

We read with interest the review by Kord-Varkaneh et al. which examined the effects of vitamin D supplementation on IGF-1 levels in humans. We believe that the article suffers from severe methodological faults and subsequently the conclusions are likely to be biased. Thus, the authors should address the mentioned limitations and update the analyses...

Campbell and colleagues recently published a randomised controlled trial investigating the effects of diets involving intermittent energy restriction versus continuous energy restriction on changes in body composition and resting metabolic rate (RMR) in resistance-trained adults[...]

Background: Eating or skipping breakfast for weight interests scientific and lay communities. Our objective was to systematically review and meta-analyze causal effects of eating versus skipping breakfast on obesity-related anthropometric outcomes in humans. Methods: Six databases were searched for obesity- and breakfast-related terms (final search...

Background: As part of a coordinated effort to expand research activity around rigor, reproducibility, and transparency (RRT) across scientific disciplines, a team of investigators at the Indiana University School of Public Health-Bloomington hosted a workshop in October 2019 with international leaders to discuss key opportunities for RRT research....

We read with interest the publication by Lightowler et al [...]

Background/Objectives Genetic contributors to obesity are frequently studied in murine models. However, the sample sizes of these studies are often small, and the data may violate assumptions of common statistical tests, such as normality of distributions. We examined whether, in these cases, type I error rates and power are affected by the choice...

Objectives A gold standard method to measure energy intake (EI) is doubly labeled water (DLW), but it is expensive and not feasible for large studies. EI from self-report (EISR) is prone to bias, but is still widely used due to convenience; however, estimated associations between EISR and outcomes are biased in many cases. Double sampling with mult...

Objectives The “traffic light diet” (TLD; or “stop light diet” among other names) categorizes foods into ‘green’, ‘yellow’, or ‘red’ groups to consume without restriction, in moderation, or minimally, respectively. It is often a component of childhood interventions targeting weight-related outcomes. The Academy of Nutrition and Dietetics Evidence A...

Childhood obesity continues to be a growing health concern and deserves evidence-based strategies to address it. One proposed nutritional approach to improve dietary patterns is referred to as the “Traffic Light Diet” (TLD) or “Stop Light Diet”, among other names, and is often included as a nutritional factor in pediatric multicomponent interventio...

Background: Whether one should eat or skip breakfast for weight is of continued interest in both the scientific and lay communities. Our objective was to systematically review and meta-analyze causal effects of eating versus skipping breakfast on obesity-related anthropometric outcomes in humans. Methods: AltHealthWatch, CINAHL, Proquest Theses and...

Dairy has been described as everything from a superfood to a poison; yet, arguments, assumptions, and data justifying these labels are not always clear. We used an issue-based information system, “dialogue mapping™,” to summarize scientific points of a live panel discussion on the putative effects of dairy on cardiovascular diseases (CVD) from a da...

The Self‐Correction Norm. Science is often described as ‘self‐correcting’. Correction of scientific errors is vital, but it does not occur spontaneously. Rather, correction depends on individual scientists behaving in accordance with the self‐correction norm (1). Some authors have suggested that failure to correct certain errors be considered scien...

Submitted to Journals of Gerontology Series A: Biological Sciences as a letter to the editor.

We read the article in Psychology of Sport and Exercise by Liu et al. (“A randomized controlled trial of coordination exercise on cognitive function in obese adolescents”) with great interest. Our interest in the article stemmed from the extraordinary differences in obesity-related outcomes reported in response to a rope-jumping intervention. We re...

Background: The Goldberg cutoffs are used to decrease bias in self-reported estimates of energy intake (EISR). Whether the cutoffs reduce and eliminate bias when used in regressions of health outcomes has not been assessed. Objective: We examined whether applying the Goldberg cutoffs to data used in nutrition studies could reliably reduce or eli...

Being able to draw accurate conclusions from childhood obesity trials is important to make advances in reversing the obesity epidemic. However, obesity research sometimes is not conducted or reported to appropriate scientific standards. To constructively draw attention to this issue, we present 10 errors that are commonly committed, illustrate each...

Background and aims: Relapse rates for psychosocial substance use disorder (SUD) treatments are high, and dropout is a robust predictor of relapse. This study aimed to estimate average dropout rates of in-person psychosocial SUD treatment and to assess predictors of dropout. Design: A comprehensive meta-analysis of dropout rates of studies of in...

Objectives: Rigor, reproducibility and transparency (RRT) awareness has expanded over the last decade. Although RRT can be improved from various aspects, we focused on type I error rates and power of commonly used statistical analyses testing mean differences of two groups, using small (n ≤ 5) to moderate sample sizes. Methods: We compared data...

Objectives: There are myriad operational definitions of the Mediterranean Diet (MedDiet) utilized in nutrition research. Variability in MedDiet definitions creates uncertainty when conducting and evaluating research, and may lead to consumer confusion and practitioner inconsistency. Therefore, we investigated and quantified heterogeneity in MedDie...

Objectives: Dairy has been described ranging from superfood to poison, but arguments, assumptions, and data used to justify these labels are not always clear. This project used "dialogue mapping" (DMing) to extract and summarize scientific points of (dis)agreement from an expert panel. Methods: A day-long panel convened 8 experts with compliment...

Objectives Intake of n-3 polyunsaturated fatty acids (PUFAs) has been reported to provide various benefits for patients with metabolic syndrome (MetS), such as reducing blood pressure and improving blood lipids, but results are inconsistent. This study aimed to investigate the effect of n-3 PUFA intake on components of MetS. Methods We searched Pu...

We commend Adams et al [...]

Science remains our best means of obtaining objective knowledge of the world, and recent concerns regarding research rigor and reproducibility highlight areas in which we can do even better. This talk will introduce concepts of rigor, reproducibility, and transparency in science in general and related to aging research in particular. Specifically,...

There is renewed interest in rigor, reproducibility, and transparency (RRT) across scientific disciplines, including aging research. For instance, one of the core aims of the Nathan Shock Centers Coordinating Center, the organizer of this symposium that is funded by the Division of Aging Biology of NIA/NIH, is to support RRT. RRT help ensure that e...

Background Skipping versus eating breakfast has been consistently associated with higher weight in observational data, but the causal effects of eating versus skipping breakfast on obesity‐related anthropometric outcomes has not been systematically reviewed and meta‐analyzed. Objective To meta‐analyze randomized controlled trials investigating the...

To the Editor In a Viewpoint,¹ Dr Guth said that the challenge of weight loss is to “convince patients to consume fewer calories” and benchmarked weight loss success against the 3500 kcal per pound rule. This view suggests that small decreases in diet calories will progressively result in substantial weight losses. However, the real relationship be...

Some aspects of science, taken at the broadest level, are universal in empirical research. These include collecting, analyzing, and reporting data. In each of these aspects, errors can and do occur. In this work, we first discuss the importance of focusing on statistical and data errors to continually improve the practice of science. We then descri...

Despite the increasing focus placed on the importance of nutrition for optimal health, nutrition as a science is often criticized in lay media and casual conversation as constantly conflicting with itself, and experts ridiculed for seeming to change their minds. Although there is much that is uncertain about the effects of foods on health, the seem...

Blinded randomized controlled trials (RCT) require participants to be uncertain if they are receiving a treatment or placebo. Although uncertainty is ideal for isolating the treatment effect from all other potential effects, it is poorly suited for estimating the treatment effect under actual conditions of intended use-when individuals are certain...

Objectives To summarise logistical aspects of recently completed systematic reviews that were registered in the International Prospective Register of Systematic Reviews (PROSPERO) registry to quantify the time and resources required to complete such projects. Design Meta-analysis. Data sources and study selection All of the 195 registered and com...

When we rely on science to inform decisions about matters such as the environment, teaching strategies, economics, government, and medicine, evidence- based decision- making can only be as reliable as the totality of the science itself. We must avoid distortions of the scientific literature such as publication bias, which is an expected systematic...

This review identifies 10 common errors and problems in the statistical analysis, design, interpretation, and reporting of obesity research and discuss how they can be avoided. The 10 topics are: 1) misinterpretation of statistical significance, 2) inappropriate testing against baseline values, 3) excessive and undisclosed multiple testing and "P-v...

Background The quality of a meta‐analysis depends on accurate estimates from original publications. Existing back‐calculation methods for point estimates [e.g., odds ratios (ORs), log(ORs), or means] and standard errors (SEs) from reported point estimates and 95% confidence intervals (CIs) can create estimates that, when forward‐calculated, do not...

Objective To quantify body weight outcomes from randomized studies using added yogurt as a weight loss intervention. Design We extracted body weight or body composition outcomes and used a random effects summary of mean differences between treatment and control groups to evaluate overall effects on body weight/body composition outcomes. Data Sour...

Background Breakfast consumption is frequently recommended for weight loss and the prevention of obesity. Although breakfast eating has been repeatedly associated with lower BMIs through numerous observational studies and meta‐analyses of observational studies, the causal effects of eating versus skipping breakfast on obesity has not been systemati...

High–fat high-sugar diet; Meal size; Meal frequency; Intrahepatic triglycerides; Statistics