scholarly journals Standardized Effect Sizes for Moderated Conditional Fixed Effects with Continuous Moderator Variables

2017 ◽  
Vol 8 ◽  
Author(s):  
Todd E. Bodner
Plant Disease ◽  
2020 ◽  
Vol 104 (6) ◽  
pp. 1736-1743
Author(s):  
Yuba R. Kandel ◽  
Carl A. Bradley ◽  
Martin I. Chilvers ◽  
Febina M. Mathew ◽  
Albert U. Tenuta ◽  
...  

In total, 52 uniform field experiments were conducted in Illinois, Indiana, Iowa, Michigan, South Dakota, and Wisconsin in the United States and Ontario, Canada from 2013 to 2017 comparing crop protection products against sudden death syndrome (SDS) of soybean. Data were analyzed using meta-analytic models to summarize the relationship between foliar disease index (FDX) and yield. For each study, correlation and regression analyses were performed separately to determine three effect sizes: Fisher’s transformation of correlation coefficients (Z r ), intercept (β0), and slope (β1). Random- and mixed-effect meta-analyses were used to summarize the effect sizes. Study- and location-specific moderator variables FDX (low < 10% and high ≥ 10%), date of planting (early = prior to 7 May, conventional = 7 to 21 May, and late = after 21 May) cultivar (susceptible and partially resistant to SDS), study location, and growing season were used as fixed effects. The overall mean effect sizes of transformed correlation coefficient [Formula: see text] r was −0.41 and different from zero (P < 0.001), indicating that yield was negatively correlated with FDX. The [Formula: see text] r was affected by disease level (P < 0.01) and cultivar (P = 0.02), with a greater effect at higher disease levels and with susceptible cultivars. The mean [Formula: see text] 0 was 4,121 kg/ha and mean [Formula: see text] 1 was −21 kg/ha/% FDX and were different from zero (P < 0.01). Results from these data indicate that, for every unit of FDX increase, yield was decreased by 0.5%. Study locations and year affected the [Formula: see text] 0 , whereas none of the moderator variables significantly affected [Formula: see text] 1.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daniel Fatori ◽  
Pedro Fonseca Zuccolo ◽  
Elizabeth Shephard ◽  
Helena Brentani ◽  
Alicia Matijasevich ◽  
...  

AbstractTo test the efficacy of a nurse home visiting program (HVP) on child development, maternal and environmental outcomes in the first years of life. We conducted a randomized controlled trial to test the efficacy of Primeiros Laços, a nurse HVP for adolescent mothers living in a poor urban area of São Paulo, Brazil. Eighty adolescent mothers were included and randomized to receive either Primeiros Laços (intervention group, n = 40) or healthcare as usual (control group, n = 40). Primeiros Laços is a home visiting intervention delivered by trained nurses that starts during the first 16 weeks of pregnancy and continues to the child’s age of 24 months. Participants were assessed by blind interviewers at 8–16 weeks of pregnancy (baseline), 30 weeks of pregnancy, and 3, 6, 12, and 24 months of child’s age. We assessed oscillatory power in the mid-range alpha frequency via electroencephalography when the children were aged 6 months. Child development was measured by the Bayley Scales of Infant Development Third Edition (BSID-III). Weight and length were measured by trained professionals and anthropometric indexes were calculated. The home environment and maternal interaction with the child was measured by the Home Observation and Measurement of the Environment. Generalized estimating equation models were used to examine intervention effects on the trajectories of outcomes. Standardized effect sizes (Cohen’s d) were calculated using marginal means from endpoint assessments of all outcomes. The trial was registered at clinicaltrial.gov: NCT02807818. Our analyses showed significant positive effects of the intervention on child expressive language development (coefficient = 0.89, 95% CI [0.18, 1.61], p = 0.014), maternal emotional/verbal responsivity (coefficient = 0.97, 95% CI [0.37, 1.58], p = 0.002), and opportunities for variety in daily stimulation (coefficient = 0.37, 95% CI [0.09, 0.66], p = 0.009). Standardized effect sizes of the intervention were small to moderate. Primeiros Laços is a promising intervention to promote child development and to improve the home environment of low-income adolescent mothers. However, considering the limitations of our study, future studies should be conducted to assess Primeiros Laços potential to benefit this population.Clinical Trial Registration: The study was registered at clinicaltrial.gov (Registration date: 21/06/2016 and Registration number: NCT02807818).


2018 ◽  
Author(s):  
Beau Gamble ◽  
David Moreau ◽  
Lynette J. Tippett ◽  
Donna Rose Addis

Reduced specificity of autobiographical memory has been well established in depression, but whether this ‘overgenerality’ extends to future thinking has not been the focus of a meta-analysis. Following a preregistered protocol, we searched six electronic databases, Google Scholar, personal libraries, and contacted authors in the field for studies matching search terms related to depression, future thinking, and specificity. We reduced an initial 7,332 results to 46 included studies, with 89 effect sizes and 4,813 total participants. Random effects meta-analytic modelling revealed a small but robust correlation between reduced future specificity and higher levels of depression (r = .13, p &lt; .001). Of the 11 moderator variables examined, the most striking effects related to the emotional valence of future thinking (p &lt; .001) and the sex of participants (p = .025). Namely, depression was linked to reduced specificity for positive (but not negative or neutral) future thinking, and the relationship was stronger in samples with a higher proportion of males. This meta-analysis contributes to our understanding of how prospection is altered in depression and dysphoria and, by revealing areas where current evidence is inconclusive, highlights key avenues for future research.


2020 ◽  
Vol 42 (2) ◽  
pp. 411-438 ◽  
Author(s):  
Akifumi Yanagisawa ◽  
Stuart Webb ◽  
Takumi Uchihara

AbstractThis meta-analysis investigated the overall effects of glossing on L2 vocabulary learning from reading and the influence of potential moderator variables: gloss format (type, language, mode) and text and learner characteristics. A total of 359 effect sizes from 42 studies (N = 3802) meeting the inclusion criteria were meta-analyzed. The results indicated that glossed reading led to significantly greater learning of words (45.3% and 33.4% on immediate and delayed posttests, respectively) than nonglossed reading (26.6% and 19.8%). Multiple-choice glosses were the most effective, and in-text glosses and glossaries were the least effective gloss types. L1 glosses yielded greater learning than L2 glosses. We found no interaction between language (L1, L2) and proficiency (beginner, intermediate, advanced), and no significant difference among modes of glossing (textual, pictorial, auditory). Learning gains were moderated by test formats (recall, recognition, other), comprehension of text, and proficiency.


2019 ◽  
Vol 14 (5) ◽  
pp. 816-834 ◽  
Author(s):  
Beau Gamble ◽  
David Moreau ◽  
Lynette J. Tippett ◽  
Donna Rose Addis

Reduced specificity of autobiographical memory has been well established in depression, but whether this overgenerality extends to future thinking has not been the focus of a meta-analysis. Following a preregistered protocol, we searched six electronic databases, Google Scholar, and personal libraries and contacted authors in the field for studies matching search terms related to depression, future thinking, and specificity. We reduced an initial 7,332 results to 46 included studies, with 89 effect sizes and 4,813 total participants. Random-effects meta-analytic modeling revealed a small but robust correlation between reduced future specificity and higher levels of depression ( r = −.13, p < .001). Of the 11 moderator variables examined, the most striking effects were related to the emotional valence of future thinking ( p < .001) and the sex of participants ( p = .025). Namely, depression was linked to reduced specificity for positive (but not negative or neutral) future thinking, and the relationship was stronger in samples with a higher proportion of males. This meta-analysis contributes to our understanding of how prospection is altered in depression and dysphoria and, by revealing areas where current evidence is inconclusive, highlights key avenues for future research.


2003 ◽  
Vol 15 (3) ◽  
pp. 243-256 ◽  
Author(s):  
Benjamin A. Sibley ◽  
Jennifer L. Etnier

The purpose of this study was to quantitatively combine and examine the results of studies pertaining to physical activity and cognition in children. Studies meeting the inclusion criteria were coded based on design and descriptive characteristics, subject characteristics, activity characteristics, and cognitive assessment method. Effect sizes (ESs) were calculated for each study and an overall ES and average ESs relative to moderator variables were then calculated. ESs (n = 125) from 44 studies were included in the analysis. The overall ES was 0.32 (SD = 0.27), which was significantly different from zero. Significant moderator variables included publication status, subject age, and type of cognitive assessment. As a result of this statistical review of the literature, it is concluded that there is a significant positive relationship between physical activity and cognitive functioning in children.


2009 ◽  
Vol 217 (1) ◽  
pp. 15-26 ◽  
Author(s):  
Geoff Cumming ◽  
Fiona Fidler

Most questions across science call for quantitative answers, ideally, a single best estimate plus information about the precision of that estimate. A confidence interval (CI) expresses both efficiently. Early experimental psychologists sought quantitative answers, but for the last half century psychology has been dominated by the nonquantitative, dichotomous thinking of null hypothesis significance testing (NHST). The authors argue that psychology should rejoin mainstream science by asking better questions – those that demand quantitative answers – and using CIs to answer them. They explain CIs and a range of ways to think about them and use them to interpret data, especially by considering CIs as prediction intervals, which provide information about replication. They explain how to calculate CIs on means, proportions, correlations, and standardized effect sizes, and illustrate symmetric and asymmetric CIs. They also argue that information provided by CIs is more useful than that provided by p values, or by values of Killeen’s prep, the probability of replication.


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