scholarly journals Evaluating differences in disease occurrence between two groups to determine the effect size of an observed factor based on a multi-variate model

2019 ◽  
Author(s):  
Hui Liu
Keyword(s):  
Effect Size ◽  
Disease Incidence ◽  
Substantial Effect ◽  
Size Difference ◽  
Intensity Level ◽  
Number Of Factors ◽  
Disease Occurrence ◽  
Pathogenic Factors ◽  
Two Factors ◽  
The Difference

Abstract Background To describe a method to determine the effect size of an observed factor for a disease by evaluating the difference in the frequency of disease occurrence between exposed and unexposed groups.Methods A model of multiple pathogenic factors was established by analyzing the number and distribution of observed factors in a study population. The difference in the incidence between two groups (exposed and unexposed) was calculated according to the model.Results The distribution of observed factors in the population did not influence the difference in disease incidence between the two groups. However, the difference in incidence between the two groups was able to correctly reflect the number of factors combined in the models, and therefore, indicates that group differences in incidence is a reasonable indicator of effect size. Difference scores <0.25 indicate that one of four or more factors plays a role in a disease; scores >0.50 indicate one of two factors plays a role in disease and implies a high intensity level of the factor.Conclusions A difference in incidence between two groups over 0.25 is suggested as an indicator of a substantial effect size.

scholarly journals Determination of the effect size of an observed factor based on a multi-variate model for evaluating practical significance of differences between two groups of case-control design

2020 ◽  
Author(s):  
Liu Hui
Keyword(s):  
Effect Size ◽  
Control Design ◽  
Substantial Effect ◽  
Case Control ◽  
Practical Significance ◽  
Size Difference ◽  
Intensity Level ◽  
Positive Ratio ◽  
The Difference ◽  
Clinically Significant

Abstract Background: To determine the effect size of an observed factor for a disease by using consistency in a cohort study (CRC) for evaluating practical significance of differences between two groups of case-control design. Methods: A model of multiple pathogenic factors was established by analyzing the number and distribution of observed factors in a study population. The difference in the incidence between two groups (exposed and unexposed) was calculated according to the model as CRC. The relationship of Youden’s index and true and false-positive ratio (TFR) in case-control design were observed with CRC. Results: The CRC was able to correctly reflect the number of factors combined in the models, and therefore, indicates that CRC is a reasonable indicator of effect size. Difference scores <0.25 indicate that one of four or more factors plays a role in a disease; scores >0.50 indicate one of two factors plays a role in disease and implies a high intensity level of the factor. TFR could correctly reflect CRC. Accordingly, a factor with an effect size (i.e., TFR) less than 6.0 should not be considered a clinically significant factor, even if the observed difference is statistically significant. Conclusions: A CRC over 0.25 OR TFR over 6.0 is suggested as an indicator of a substantial effect size.

scholarly journals Determination of the effect size of an observed factor based on a multi-variate model for evaluating practical significance of differences between two groups of case-control design

2020 ◽  
Author(s):  
Liu Hui
Keyword(s):  
Effect Size ◽  
Control Design ◽  
Substantial Effect ◽  
Case Control ◽  
Practical Significance ◽  
Size Difference ◽  
Intensity Level ◽  
Positive Ratio ◽  
The Difference ◽  
Clinically Significant

Abstract Background To determine the effect size of an observed factor for a disease by using consistency in a cohort study (CRC) for evaluating practical significance of differences between two groups of case-control design. Methods A model of multiple pathogenic factors was established by analyzing the number and distribution of observed factors in a study population. The difference in the incidence between two groups (exposed and unexposed) was calculated according to the model as CRC. The relationship of Youden’s index and true and false-positive ratio (TFR) in case-control design were observed with CRC. Results The CRC was able to correctly reflect the number of factors combined in the models, and therefore, indicates that CRC is a reasonable indicator of effect size. Difference scores <0.25 indicate that one of four or more factors plays a role in a disease; scores >0.50 indicate one of two factors plays a role in disease and implies a high intensity level of the factor. TFR could correctly reflect CRC. Accordingly, a factor with an effect size (i.e., CRC) less than 6.0 should not be considered a clinically significant factor, even if the observed difference is statistically significant. Conclusions A CRC over 0.25 OR TFR over 6.0 is suggested as an indicator of a substantial effect size.

Slow Down You’re Moving Too Fast

2015 ◽  
Vol 27 (2) ◽  
pp. 53-63 ◽  
Author(s):  
Annie Lang ◽  
Nancy Schwartz ◽  
Sharon Mayell
Keyword(s):  
Older Adults ◽  
Cognitive Aging ◽  
Attention And Memory ◽  
Younger Adults ◽  
Media Messages ◽  
Two Factors ◽  
The Difference

The study reported here compared how younger and older adults processed the same set of media messages which were selected to vary on two factors, arousing content and valence. Results showed that older and younger adults had similar arousal responses but different patterns of attention and memory. Older adults paid more attention to all messages than did younger adults. However, this attention did not translate into greater memory. Older and younger adults had similar levels of memory for slow-paced messages, but younger adults outperformed older adults significantly as pacing increased, and the difference was larger for arousing compared with calm messages. The differences found are in line with predictions made based on the cognitive-aging literature.

scholarly journals Transdiagnostic comparison of visual working memory capacity in bipolar disorder and schizophrenia

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Catherine V. Barnes-Scheufler ◽  
Caroline Passow ◽  
Lara Rösler ◽  
Jutta S. Mayer ◽  
Viola Oertel ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Working Memory ◽  
Visual Working Memory ◽  
Effect Size ◽  
Working Memory Capacity ◽  
Memory Capacity ◽  
Medium Effect ◽  
Full Spectrum ◽  
Small Effect Size ◽  
The Difference

Abstract Background Impaired working memory is a core cognitive deficit in both bipolar disorder and schizophrenia. Its study might yield crucial insights into the underpinnings of both disorders on the cognitive and neurophysiological level. Visual working memory capacity is a particularly promising construct for such translational studies. However, it has not yet been investigated across the full spectrum of both disorders. The aim of our study was to compare the degree of reductions of visual working memory capacity in patients with bipolar disorder (PBD) and patients with schizophrenia (PSZ) using a paradigm well established in cognitive neuroscience. Methods 62 PBD, 64 PSZ, and 70 healthy controls (HC) completed a canonical visual change detection task. Participants had to encode the color of four circles and indicate after a short delay whether the color of one of the circles had changed or not. We estimated working memory capacity using Pashler’s K. Results Working memory capacity was significantly reduced in both PBD and PSZ compared to HC. We observed a small effect size (r = .202) for the difference between HC and PBD and a medium effect size (r = .370) for the difference between HC and PSZ. Working memory capacity in PSZ was also significantly reduced compared to PBD with a small effect size (r = .201). Thus, PBD showed an intermediate level of impairment. Conclusions These findings provide evidence for a gradient of reduced working memory capacity in bipolar disorder and schizophrenia, with PSZ showing the strongest degree of impairment. This underscores the importance of disturbed information processing for both bipolar disorder and schizophrenia. Our results are compatible with the cognitive manifestation of a neurodevelopmental gradient affecting bipolar disorder to a lesser degree than schizophrenia. They also highlight the relevance of visual working memory capacity for the development of both behavior- and brain-based transdiagnostic biomarkers.

scholarly journals Morphological consistency of bilateral hip joints in adults based on the X-ray and CT data

2021 ◽  
Author(s):  
Ran Zhao ◽  
Hong Cai ◽  
Hua Tian ◽  
Ke Zhang
Keyword(s):  
Hip Joint ◽  
Morphological Difference ◽  
Medullary Cavity ◽  
Size Difference ◽  
Single Plane ◽  
X Ray ◽  
Stem Size ◽  
The Difference ◽  
Ct Data ◽  
Anatomical Parameters

Abstract Purpose The application of the anatomical parameters of the contralateral hip joint to guide the preoperative template of the affected side relies on the bilateral hip symmetry. We investigated the bilateral hip symmetry and range of anatomical variations by measurement and comparison of bilateral hip anatomical parameters. Methods This study included 224 patients (448 hips) who were diagnosed with osteoarthritis (OA) and avascular necrosis (AVN) of the femur head, and underwent bilateral primary total hip arthroplasty (THA) in our hospital from January 2012 to August 2020. Imaging data included 224 patients X-ray and 30 CT data at the end of the cohort. Anatomical parameters, including the acetabular abduction angle and trochanteric height, were measured using the Noble method. Postoperative measurements included stem size, difference of leg length and offset. Results Except for the isthmus width, there were no significant differences in the anatomical morphology of the hip joint. Among the demographic factors, there was a correlation between body weight and NSA. Among various anatomical parameters, a correlation was present between medullary cavity widths of T + 20, T, and T − 20. The difference in the use of stem size is not due to the morphological difference of bilateral medullary cavity, but due to the different of 1- or 2-stage surgery. Conclusion Bilateral symmetry was present among the patients with normal morphology of the hip medullary cavity, theoretically confirming the feasibility of structural reconstruction of the hip joint using the hip joint on the uninjured side. Additionally, the difference in the morphology of the hip medullary cavity is not present in a single plane but is synergistically affected by multiple adjacent planes.

scholarly journals An experimental and theoretical investigation of diffusion in a two-phase alloy

1948 ◽  
Vol 192 (1031) ◽  
pp. 575-592 ◽  
Keyword(s):  
Free Energy ◽  
Single Phase ◽  
Phase State ◽  
Theoretical Treatment ◽  
Research Association ◽  
Essential Difference ◽  
Two Phase ◽  
Two Factors ◽  
Order Of Magnitude ◽  
The Difference

The present paper describes an investigation of diffusion in the solid state. Previous experimental work has been confined to the case in which the free energy of a mixture is a minimum for the single-phase state, and diffusion decreases local differences of concentration. This may be called ‘diffusion downhill’. However, it is possible for the free energy to be a minimum for the two-phase state; diffusion may then increase differences of concentration; and so may be called ‘diffusion uphill’. Becker (1937) has proposed a simple theoretical treatment of these two types of diffusion in a binary alloy. The present paper describes an experimental test of this theory, using the unusual properties of the alloy Cu 4 FeNi 3 . This alloy is single phase above 800° C and two-phase at lower temperatures, both the phases being face-centred cubic; the essential difference between the two phases is their content of copper. On dissociating from one phase into two the alloy develops a series of intermediate structures showing striking X-ray patterns which are very sensitive to changes of structure. It was found possible to utilize these results for a quantitative study of diffusion ‘uphill’ and ‘downhill’ in the alloy. The experimental results, which can be expressed very simply, are in fair agreement with conclusions drawn from Becker’s theory. It was found that Fick’s equation, dc / dt = D d2c / dx2 , can, within the limits of error, be applied in all cases, with the modification that c denotes the difference of the measured copper concentration from its equilibrium value. The theory postulates that D is the product of two factors, of which one is D 0f the coefficient of diffusion that would be measured if the alloy were an ideal solid solution. The theory is able to calculate D/D 0 , if only in first approximation, and the experiments confirm this calculation. It was found that in most cases the speed of diffusion—‘uphill’ or ‘downhill’—has the order of magnitude of D 0 . * Now with British Electrical Research Association.

A Critique and Improvement of the CL Common Language Effect Size Statistics of McGraw and Wong

2000 ◽  
Vol 25 (2) ◽  
pp. 101-132 ◽  
Author(s):  
András Vargha ◽  
Harold D. Delaney
Keyword(s):  
Effect Size ◽  
Continuous Distribution ◽  
Interval Estimation ◽  
Continuous Variable ◽  
Common Language ◽  
Exact Methods ◽  
Normal Distributions ◽  
The Difference ◽  
Discrete Values ◽  
Two Populations

McGraw and Wong (1992) described an appealing index of effect size, called CL, which measures the difference between two populations in terms of the probability that a score sampled at random from the first population will be greater than a score sampled at random from the second. McGraw and Wong introduced this "common language effect size statistic" for normal distributions and then proposed an approximate estimation for any continuous distribution. In addition, they generalized CL to the n-group case, the correlated samples case, and the discrete values case. In the current paper a different generalization of CL, called the A measure of stochastic superiority, is proposed, which may be directly applied for any discrete or continuous variable that is at least ordinally scaled. Exact methods for point and interval estimation as well as the significance tests of the A = .5 hypothesis are provided. New generalizations ofCL are provided for the multi-group and correlated samples cases.

Investigation of Regression-Based Effect Size Methods Developed in Single-Subject Studies

2021 ◽  
pp. 014544552110540
Author(s):  
Nihal Sen
Keyword(s):  
Effect Size ◽  
Experimental Studies ◽  
Single Subject ◽  
Single Subject Design ◽  
Data Set ◽  
Design Studies ◽  
Sample Data ◽  
The Difference ◽  
D Values ◽  
Effect Size Calculation

The purpose of this study is to provide a brief introduction to effect size calculation in single-subject design studies, including a description of nonparametric and regression-based effect sizes. We then focus the rest of the tutorial on common regression-based methods used to calculate effect size in single-subject experimental studies. We start by first describing the difference between five regression-based methods (Gorsuch, White et al., Center et al., Allison and Gorman, Huitema and McKean). This is followed by an example using the five regression-based effect size methods and a demonstration how these methods can be applied using a sample data set. In this way, the question of how the values obtained from different effect size methods differ was answered. The specific regression models used in these five regression-based methods and how these models can be obtained from the SPSS program were shown. R2 values obtained from these five methods were converted to Cohen’s d value and compared in this study. The d values obtained from the same data set were estimated as 0.003, 0.357, 2.180, 3.470, and 2.108 for the Allison and Gorman, Gorsuch, White et al., Center et al., as well as for Huitema and McKean methods, respectively. A brief description of selected statistical programs available to conduct regression-based methods was given.

HYPOCHROMIC MICROCYTIC ANEMIA OF INFANCY: IRON DEPLETION AS A FACTOR

PEDIATRICS ◽  
1956 ◽  
Vol 18 (6) ◽  
pp. 959-978
Author(s):  
Hugh W. Josephs
Keyword(s):  
Iron Deficiency ◽  
Severe Infection ◽  
Microcytic Anemia ◽  
Severe Anemia ◽  
Iron Depletion ◽  
Hypochromic Microcytic Anemia ◽  
Premature Babies ◽  
Number Of Factors ◽  
The Difference ◽  
Insight Into

In this work the author has attempted to gain insight into the significance of iron depletion by the use of 4 simple calculations, justification for which is found in recent articles. These are: (a) iron with which the infant is born; (b) iron retained from the food; (c) iron being used by the tissues and therefore unavailable for hemoglobin, and (d) iron combined with the total mass of hemoglobin. With these 4 figures it is possible to estimate the iron still potentially available for use (the "reserves" or "stones"). When the difference between a + b and c + d has reached about zero, depletion is considered to exist. The following characteristics of depletion may be emphasized: Depletion is the result of gain in weight and maximum possible usage of iron. It is therefore a normal result of growth and need not be associated with anemia. As soon as depletion has occurred, the organism is thereafter dependent on current absorption of iron. This is ordinarily sufficient, even with a diet of milk alone, to maintain an adequate concentration of hemoglobin after about 8 to 10 months of age. Severe anemia due to depletion alone is practically confined to premature babies whose relative gain in weight is rapid. Severe anemia in other than premature babies is the result of a number of factors by which iron becomes unavailable or is actually diverted from hemoglobin to storage. Response to iron medication is considerably better in infants with depletion than in those in whom some factor is present that interferes with iron utilization, and which is not connected by the mere giving of iron. The dependence on current absorption, whether the result of depletion or non-availability, introduces a certain precariousness which is apparently characteristic of this time of life. The organism gets along from day to day if nothing happens, but may not be able to meet an emergency, whether this appears as a rapid gain in weight, or a necessity to repair damage done by severe infection. If we consider iron deficiency as the cause of anemia, we can think of deficiency as due to a number of factors of which depletion is only one. The development and characteristics of depletion have been considered in this paper; other factors in iron deficiency will be considered in subsequent papers.

The opposite and antagonistic effects of the closely related POU family transcription factors Brn-3a and Brn-3b on the activity of a target promoter are dependent on differences in the POU domain

1994 ◽  
Vol 14 (10) ◽  
pp. 6907-6914
Author(s):  
P J Morris ◽  
T Theil ◽  
C J Ring ◽  
K A Lillycrop ◽  
T Moroy ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Promoter Activity ◽  
Group Iv ◽  
Promoter Activation ◽  
Antagonistic Effects ◽  
Pou Domain ◽  
Close Relationship ◽  
Two Factors ◽  
The Difference ◽  
Target Promoter

The Brn-3a, Brn-3b, and Brn-3c POU family transcription factors are closely related to one another and are members of the group IV subfamily of POU factors. Here we show that despite this close relationship, the factors have different effects on the activity of a target promoter: Brn-3a and Brn-3c stimulate the promoter whereas Brn-3b represses it. Moreover, Brn-3b can antagonize the stimulatory effect of Brn-3a on promoter activity and can also inhibit promoter activation by the Oct-2.1 POU factor. The difference in the transactivation activities of Brn-3a and Brn-3b is dependent upon the C-terminal region containing the POU domain of the two proteins, since exchange of this domain between the two factors converts Brn-3a into a repressor and Brn-3b into an activator.

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