PD-0130: Review and meta-analysis of prognostic PET imaging studies: Evidence of publication bias

2014 ◽  
Vol 111 ◽  
pp. S50-S51
Author(s):  
M.M. Clausen ◽  
I.R. Vogelius ◽  
S.A. Engelholm ◽  
A. Kjær ◽  
S.M. Bentzen
Diagnostics ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1030
Author(s):  
Malene M. Clausen ◽  
Ivan R. Vogelius ◽  
Andreas Kjær ◽  
Søren M. Bentzen

Positron emission tomography (PET) imaging with 2-deoxy-2-[18F]-fluorodeoxyglucose (FDG) was proposed as prognostic marker in radiotherapy. Various uptake metrics and cut points were used, potentially leading to inflated effect estimates. Here, we performed a meta-analysis and systematic review of the prognostic value of pretreatment FDG–PET in head and neck squamous cell carcinoma (HNSCC) and non-small cell lung cancer (NSCLC), with tests for publication bias. Hazard ratio (HR) for overall survival (OS), disease free survival (DFS), and local control was extracted or derived from the 57 studies included. Test for publication bias was performed, and the number of statistical tests and cut-point optimizations were registered. Eggers regression related to correlation of SUVmax with OS/DFS yielded p = 0.08/p = 0.02 for HNSCC and p < 0.001/p = 0.014 for NSCLC. No outcomes showed significant correlation with SUVmax, when adjusting for publication bias effect, whereas all four showed a correlation in the conventional meta-analysis. The number of statistical tests and cut points were high with no indication of improvement over time. Our analysis showed significant evidence of publication bias leading to inflated estimates of the prognostic value of SUVmax. We suggest that improved management of these complexities, including predefined statistical analysis plans, are critical for a reliable assessment of FDG–PET.


2017 ◽  
Vol 89 (2) ◽  
pp. 185-196 ◽  
Author(s):  
Flavia Niccolini ◽  
Gennaro Pagano ◽  
Paolo Fusar-Poli ◽  
Andrew Wood ◽  
Ladislav Mrzljak ◽  
...  

BackgroundOver the past years, positron emission tomography (PET) imaging studies have investigated striatal molecular changes in premanifest and manifest Huntington’s disease (HD) gene expansion carriers (HDGECs), but they have yielded inconsistent results.ObjectiveTo systematically examine the evidence of striatal molecular alterations in manifest and premanifest HDGECs as measured by PET imaging studies.MethodsMEDLINE, ISI Web of Science, Cochrane Library and Scopus databases were searched for articles published until 7 June 2017 that included PET studies in manifest and premanifest HDGECs. Meta-analyses were conducted with random effect models, and heterogeneity was addressed with I2 index, controlling for publication bias and quality of study. The primary outcome was the standardised mean difference (SMD) of PET uptakes in the whole striatum, caudate and putamen in manifest and premanifest HDGECs compared with healthy controls (HCs).ResultsTwenty-four out of 63 PET studies in premanifest (n=158) and manifest (n=191) HDGECs and HCs (n=333) were included in the meta-analysis. Premanifest and manifest HDGECs showed significant decreases in dopamine D2 receptors in caudate (SMD=−1.233, 95% CI −1.753 to −0.713, p<0.0001; SMD=−5.792, 95% CI −7.695 to −3.890, p<0.0001) and putamen (SMD=−1.479, 95% CI −1.965 to −0.992, p<0.0001; SMD=−5.053, 95% CI −6.558 to −3.549, p<0.0001), in glucose metabolism in caudate (SMD=−0.758, 95% CI −1.139 to −0.376, p<0.0001; SMD=−3.738, 95% CI −4.880 to −2.597, p<0.0001) and putamen (SMD=−2.462, 95% CI −4.208 to −0.717, p=0.006; SMD=−1.650, 95% CI −2.842 to −0.458, p<0.001) and in striatal PDE10A binding (SMD=−1.663, 95% CI −2.603 to −0.723, p=0.001; SMD=−2.445, 95% CI −3.371 to −1.519, p<0.001).ConclusionsPET imaging has the potential to detect striatal molecular changes even at the early premanifest stage of HD, which are relevant to the neuropathological mechanisms underlying the development of the disease.


2019 ◽  
Author(s):  
Amanda Kvarven ◽  
Eirik Strømland ◽  
Magnus Johannesson

Andrews &amp; Kasy (2019) propose an approach for adjusting effect sizes in meta-analysis for publication bias. We use the Andrews-Kasy estimator to adjust the result of 15 meta-analyses and compare the adjusted results to 15 large-scale multiple labs replication studies estimating the same effects. The pre-registered replications provide precisely estimated effect sizes, which do not suffer from publication bias. The Andrews-Kasy approach leads to a moderate reduction of the inflated effect sizes in the meta-analyses. However, the approach still overestimates effect sizes by a factor of about two or more and has an estimated false positive rate of between 57% and 100%.


2017 ◽  
Author(s):  
Nicholas Alvaro Coles ◽  
Jeff T. Larsen ◽  
Heather Lench

The facial feedback hypothesis suggests that an individual’s experience of emotion is influenced by feedback from their facial movements. To evaluate the cumulative evidence for this hypothesis, we conducted a meta-analysis on 286 effect sizes derived from 138 studies that manipulated facial feedback and collected emotion self-reports. Using random effects meta-regression with robust variance estimates, we found that the overall effect of facial feedback was significant, but small. Results also indicated that feedback effects are stronger in some circumstances than others. We examined 12 potential moderators, and three were associated with differences in effect sizes. 1. Type of emotional outcome: Facial feedback influenced emotional experience (e.g., reported amusement) and, to a greater degree, affective judgments of a stimulus (e.g., the objective funniness of a cartoon). Three publication bias detection methods did not reveal evidence of publication bias in studies examining the effects of facial feedback on emotional experience, but all three methods revealed evidence of publication bias in studies examining affective judgments. 2. Presence of emotional stimuli: Facial feedback effects on emotional experience were larger in the absence of emotionally evocative stimuli (e.g., cartoons). 3. Type of stimuli: When participants were presented with emotionally evocative stimuli, facial feedback effects were larger in the presence of some types of stimuli (e.g., emotional sentences) than others (e.g., pictures). The available evidence supports the facial feedback hypothesis’ central claim that facial feedback influences emotional experience, although these effects tend to be small and heterogeneous.


2021 ◽  
Vol 12 ◽  
pp. 215013272199364
Author(s):  
Robel Hussen Kabthymer ◽  
Solomon Nega Techane ◽  
Temesgen Muche ◽  
Helen Ali Ewune ◽  
Semagn Mekonnen Abate ◽  
...  

Background: Over-nutrition and diet-linked non-communicable morbidities are showing increasing trend overtime. Even if there are different factors that affect the change in BMI other than ART, several authors have reported increases in BMI among PLHIV on treatment that are equal to or surpass the general population. This study is aimed to estimate the prevalence of obesity and overweight among adult HIV infected peoples taking ART in Ethiopia. Method: PubMed, CINAHL, Web of science, global health and Google scholar electronic databases were used to perform a systematic literature search. Two authors independently extracted all the necessary data using a structured data extraction format. Data analysis was done using STATA Version 14. The heterogeneity of the studies was assessed by using I2 test. A random-effects model was used to estimate the pooled prevalence. Publication bias was checked using Funnel plot and Egger’s test. Result: Two thousand seven hundred and fifty-one studies were reviewed and 13 studies fulfilling the inclusion criteria were included in the meta-analysis. The meta-analysis of 13 studies, comprising 4994 participants resulted in pooled prevalence of overweight to be 17.85% (95% CI: 12.22-23.47). Whereas, the pooled prevalence of overweight was found to be 3.90 (95% CI: 2.31-5.49) but after adjusting for publication bias using trim and fill analysis it has become 3.58 (95% CI: 2.04-5.13). Magnitude of both overweight and obesity was higher in studies conducted in Addis Ababa, studies done after 2016 and studies having sample size of less than 400, in subgroup analysis. Conclusion: The magnitude of overweight and obesity among HIV infected peoples taking ART in Ethiopia is high. There is a need to have a routine screening to PLWHA on the risk of over-nutrition in order to facilitate early detection.


2021 ◽  
pp. 097226292198987
Author(s):  
Sakshi Vashisht ◽  
Poonam Kaushal ◽  
Ravi Vashisht

This study conducted a systematic review and meta-analysis to examine the relationship between emotional intelligence, personality variables (Big V personality traits, self-esteem, self-efficacy, optimism and proactive personality) and career adaptability of students. Data were coded on CMA software version 3.0. Product–moment correlation coefficient (r) was considered as the effect size measure for this study. Publication bias was assessed using Egger’s regression test along with Orwin’s fail-safe N, but no significant publication bias was detected. From the results of 54 studies, it was found that all variables of the study had meta-analytic correlation with career adaptability of students. For heterogeneity, subgroup analysis was conducted, and significant differences were found.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jing Li ◽  
Yinzi Chen ◽  
Xiling Wang ◽  
Hongjie Yu

AbstractInfluenza causes substantial morbidity and mortality. Many original studies have been carried out to estimate disease burden of influenza in mainland China, while the full disease burden has not yet been systematically reviewed. We did a systematic review and meta-analysis to assess the burden of influenza-associated mortality, hospitalization, and outpatient visit in mainland China. We searched 3 English and 4 Chinese databases with studies published from 2005 to 2019. Studies reporting population-based rates of mortality, hospitalization, or outpatient visit attributed to seasonal influenza were included in the analysis. Fixed-effects or random-effects model was used to calculate pooled estimates of influenza-associated mortality depending on the degree of heterogeneity. Meta-regression was applied to explore the sources of heterogeneity. Publication bias was assessed by funnel plots and Egger’s test. We identified 30 studies eligible for inclusion with 17, 8, 5 studies reporting mortality, hospitalization, and outpatient visit associated with influenza, respectively. The pooled influenza-associated all-cause mortality rates were 14.33 and 122.79 per 100,000 persons for all ages and ≥ 65 years age groups, respectively. Studies were highly heterogeneous in aspects of age group, cause of death, statistical model, geographic location, and study period, and these factors could explain 60.14% of the heterogeneity in influenza-associated mortality. No significant publication bias existed in estimates of influenza-associated all-cause mortality. Children aged < 5 years were observed with the highest rates of influenza-associated hospitalizations and ILI outpatient visits. People aged ≥ 65 years and < 5 years contribute mostly to mortality and morbidity burden due to influenza, which calls for targeted vaccination policy for older adults and younger children in mainland China.


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