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At least 19 recordsLinked to original sources
PubMed2026

Understanding and Usefulness of Effect Size and Certainty of Evidence: A Cross-Sectional Survey of Evidence-Based Practice Competencies Among US Registered Dietitians.

INTRODUCTION: Understanding of absolute and relative effect estimates, and determining effect size and certainty of evidence corresponding to effect estimates, represent fundamental evidence-based practice competencies that promote informed clinical decision-making. While research has been conducted in the medical profession, based on our literature review there is no published research on these competencies in the nutrition and dietetics profession. METHODS: Among registered dietitians, our main objectives were to assess (1) their understanding and perceived usefulness of three absolute and two relative effect estimate approaches to determine effect size, (2) their perceived usefulness of certainty of evidence, and (3) factors influencing their understanding and perceived usefulness. We conducted a web-based, cross-sectional survey by recruiting dietitians from the Academy of Nutrition and Dietetics (United States). Participants received effect estimates based on hypothetical dietary interventions vs. usual diet for reducing myocardial infarction risk. RESULTS: Of the 11,050 dietitians who received the survey link, 210 participated, and only completers (n = 114) were included in our analysis. Participants demonstrated a similar understanding of the relative (27.6%) and absolute (27.5%) effect estimates, with Risk Difference being the best understood approach and Number Needed to Treat being the least (30.7% vs. 24.6% correct responses). While perceived usefulness scores were similar between five approaches, they were highest when data was presented as Relative Risk [mean (SD): 4.82 (1.50)]. Dietitians rated the usefulness of certainty of evidence favorably [mean (SD): 5.07 (1.83), on a 7-point scale], and no factors were associated with correct understanding. CONCLUSION: Dietitians may have limited understanding of effect size thresholds presented in our survey, a finding mostly consistent with surveys of other health professionals. To optimize informed decision-making between dietitians and clients, dietetic programs and continuing education platforms should consider additional training on effect estimate approaches (relative and absolute), and determining effect sizes and certainty of evidence for effect estimates.

Clinical nutrition↗
PubMed2025

ESPClust: unsupervised identification of modifiers for the effect size profile in omics association studies.

MOTIVATION: High-throughput omics technologies have revolutionized the identification of associations between individual traits and underlying biological characteristics, but still use 'one effect-size fits all' approaches. While covariates are often used, their potential as effect modifiers often remains unexplored. RESULTS: We propose ESPClust, a novel unsupervised method designed to identify covariates that modify the effect size of associations between sets of omics variables and outcomes. By extending the concept of moderators to encompass multiple exposures, ESPClust analyses the effect size profile (ESP) to identify regions in covariate space with different ESP, enabling the discovery of subpopulations with distinct associations. Applying ESPClust to synthetic data, insulin resistance and COVID-19 symptom manifestation, we demonstrate its versatility and ability to uncover nuanced effect size modifications that traditional analyses may overlook. By integrating information from multiple exposures, ESPClust identifies effect size modifiers in datasets that are too small for traditional univariate stratified analyses. This method provides a robust framework for understanding complex omics data and holds promise for personalised medicine. AVAILABILITY AND IMPLEMENTATION: The source code ESPClust is available at https://github.com/fjpreche/ESPClust.git. It can be installed via Python package repositories as 'pip install ESPClust==1.1.0'.

Humans↗
PubMed2026

Correlations between causal effect sizes of proximal SNPs vary with functional annotations and implicate stabilizing selection.

Causal disease effect sizes of proximal single-nucleotide polymorphisms (SNPs) are widely assumed to be independent but could be correlated. Here we introduce a new method, linkage disequilibrium SNP-pair effect correlation regression (LDSPEC), to estimate the correlation of causal disease effect sizes of derived alleles between proximal SNPs; LDSPEC produced robust estimates in simulations. Analyzing 70 UK Biobank diseases and traits (average N = 305,646), we detected significantly non-zero SNP-pair effect correlations (for example, -0.37 ± 0.09 for low-frequency positive linkage disequilibrium 0-100-bp SNP pairs) that decayed with distance and varied with allele frequency and linkage disequilibrium between SNPs. SNP pairs with shared functions had stronger effect correlations that spanned longer genomic distances. Consequently, SNP heritability estimates were smaller than estimates of the sum of causal effect size variances across SNPs, particularly for certain functional annotations. We recapitulated our findings via forward simulations involving stabilizing selection, implicating the action of linkage masking, whereby haplotypes containing linked SNPs with opposite effects on disease have reduced effects on fitness and escape negative selection.

Polymorphism, Single Nucleotide↗
PubMed1992

Specific cesium activity in freshwater fish and the size effect.

The specific Cs-137 activity of muscle tissue of silver carp (Hypophthalmichthys molitrix) from the cooling pond of the Chernobyl nuclear power plant caught in 1987 and 1988 increased almost linearly with fish weight ("size effect") in contrast to liver tissue, whose specific activity remained independent of weight. A kinetic model for uptake and excretion was developed to describe the size effect in muscle tissue by introducing a weight-dependent Cs biological half-time to fish. Similar size effects of specific Cs-137 activity were also found for other species of fish from the cooling pond, but were primarily attributed to changes in feeding habits with increasing weight of fish rather than to metabolic changes, since the specific Cs-137 activity both of muscle and liver tissue increased with fish weight for those species in contrast to silver carp.

Accidents↗
PubMed1977

The effective size of a natural drosophila subobscura population.

The effective size of a natural Drosophila subobscura population has been computed by drawing together various pieces of ecological information. The value, for both variance and inbreeding effective numbers, is approximately 400. This is largely due to reductions caused by a winter bottleneck and non-random distributions of family sizes. Areas where such estimates might be refined further are pointed out, and the implications of the results are discussed.

Animals↗
PubMed1992

Effective size of nonrandom mating populations.

Nonrandom mating whereby parents are related is expected to cause a reduction in effective population size because their gene frequencies are correlated and this will increase the genetic drift. The published equation for the variance effective size, Ne, which includes the possibility of nonrandom mating, does not take into account such a correlation, however. Further, previous equations to predict effective sizes in populations with partial sib mating are shown to be different, but also incorrect. In this paper, a corrected form of these equations is derived and checked by stochastic simulation. For the case of stable census number, N, and equal progeny distributions for each sex, the equation is [formula: see text], where Sk2 is the variance of family size and alpha is the departure from Hardy-Weinberg proportions. For a Poisson distribution of family size (Sk2 = 2), it reduces to Ne = N/(1 + alpha), as when inbreeding is due to selfing. When nonrandom mating occurs because there is a specified system of partial inbreeding every generation, alpha can be substituted by Wright's FIS statistic, to give the effective size as a function of the proportion of inbred mates.

Breeding↗
PubMed1979

Benoxaprofen, a new anti-inflammatory agent: particle-size effect on dissolution rate and oral absorption in humans.

The particle-size effect of benoxaprofen, a new nonsteroidal anti-inflammatory agent, on the in vitro dissolution rate and oral absorption in humans was evaluated. Ten normal subjects participated in a randomized crossover-designed absorption study with two sieved particle-size formulations: one with crystals larger than 60 mesh (mean equivalent spherical diameter = 640 micron) and the other with crystals smaller than 100 mesh (mean equivalent spherical diameter = 67 micron). Plasma drug concentrations and urinary drug excretion were used to determine the relative absorption of the two formulations. The standard USP procedure was used for the dissolution study. Particle size had a dramatic effect on both the in vitro drug dissolution and its oral absorption in humans. In vitro, the smaller crystals dissolved more rapidly and more efficiently than the larger crystals. In vivo, the smaller crystals produced higher plasma concentrations, more rapid peak concentration attainment, and more drug excreted in the urine.

Anti-Inflammatory Agents↗
PubMed1992

Size effects in visual recognition memory are determined by perceived size.

Recognition memory for shapes has been shown to depend on differences between the size of shapes at the time of encoding and at the time of the memory test (Jolicoeur, 1987). Experiment 1 of the present paper replicates this effect and establishes a set of parameters used in the subsequent experiments. Experiment 2 considers the results of Experiment 1 in light of the distinction between "perceived" size, which, under normal viewing conditions, varies minimally with changes in distance between the observer and object, and "retinal" size, which varies proportionally with viewing distance as an object is moved closer to or farther from an observer. Subjects studied novel shapes and performed a recognition memory test in which the distance from the subject to the viewing screen at the time of testing was different from that at the time of encoding. The viewing distance and the size of the shapes were manipulated such that perceived and retinal sizes were dissociated. The results suggest that the size-congruency effect in memory for visual shape occurs as a result of changes in the perceived size of shapes between the encoding and the testing phases, with little or no contribution of retinal size per se.

Distance Perception↗
PubMed1978

Vertical disparity detection: is there an induced size effect?

Horizontal, vertical, and over-all size differences were introduced in the retinal images of the two eyes of normal subjects during brief presentations of simple foveal targets. Horizontal disparities, whether accompanied by vertical disparities or not, induced the appearance of a rotation of the target around a vertical axis out of the frontal plane, according to the expectation from geometry, but vertical disparities had no effect. Over-all size changes in one eye induced the effect of the horizontal component. Threshold experiments showed that even with practice and error feedback, vertical disparity detection has at most only one-tenth the sensitivity of horizontal disparity detection. Although at variance with findings on the induced size effect obtained under more complex observation conditions, these results confirm that the processing of horizontal disparity plays a special role in the integration of the signals coming from the two eyes.

Depth Perception↗
PubMed2026

The shape of fitness functions and the distribution of mutational effect sizes jointly limit adaptation by regulatory mutations.

Mutations in gene regulatory regions have been shown to play a role in rapid adaptation, but the factors determining their contribution are largely unknown. Here, using the metabolic enzyme cytosine deaminase of budding yeast, we examine whether adaptation to 5-fluorocytosine, which requires reduced cytosine deamination and can readily arise from amino acid substitutions, may be reached by single promoter mutations. We generated all single-nucleotide substitutions and indels in the FCY1 promoter and assayed the resulting mutants in presence of 5-fluorocytosine. This revealed that no promoter mutation is sufficient for adaptation to occur. We next investigated how this inaccessibility of adaptation arises by combining large-scale expression measurements with the experimental characterization of the corresponding expression-fitness function. These experiments showed that the shape of this function precludes single promoter mutations from being adaptive. Although 24% of mutations significantly affect expression, the fitness curve is flat around wild-type level. As such, adaptation can only emerge from a severe reduction of expression, which cannot occur from a single mutation in the promoter. Our results show that the contribution of regulatory mutations to rapid adaptation depends not only on the distribution of mutational effect sizes on expression level but also on the shape of the function linking fitness to expression levels.

Promoter Regions, Genetic↗
PubMed1976

The gating currents of sodium channels: pore-population-size effects.

Sodium-channel behavior has been modeled in order to determine the answer to the following question: How large must a population of "on-off" sodium pores be before the inherently random behavior of the individual channels becomes smoothed to yield the expected gating current-conductance relationships which would be predicted from an infinite pore array? Results of this analysis show that for the "opening" situation, an excellent fit was obtained whenever more than about 10 pores were considered. Significant discrepancies were observed in the "closing" situation, however, for pore arrays of 50 or less. Marked hysteresis is apparent in the behavior of small port populations.

Membranes↗
PubMedDate not supplied

Effective size of the transverse dimension of x-ray-tube focal spots.

Corrections for nonuniform x-ray intensity distributions have been computed for the dimension perpendicular to the anode-cathode axis of x-ray-tube focal spots. These correction factors were developed from comparison of OTFs for focal spots with uniform intensity distributions to those for focal spots with symmetric double-peaked intensity distributions.

Technology, Radiologic↗
PubMed1992

Reporting the size of effects in research studies to facilitate assessment of practical or clinical significance.

"Statistically significant" results may lack practical or clinical significance, and the description of results in reports of research studies is frequently incomplete or misleading in presentation of data necessary to assess such significance (effect sizes). Various common presentations are discussed, and one method of presentation of results is proposed that not only encompasses all the others, but enhances the scope of useful information conveyed in a research report. The results of the Infant Health and Development Program (IHDP) are used to illustrate the method.

Child Behavior↗