scholarly journals A matrix‐based method of moments for fitting the multivariate random effects model for meta‐analysis and meta‐regression

2013 ◽  
Vol 55 (2) ◽  
pp. 231-245 ◽  
Author(s):  
Dan Jackson ◽  
Ian R. White ◽  
Richard D. Riley
Author(s):  
Denis M. Pelletier ◽  
Guillaume Lacerte ◽  
Eric D.B. Goulet

Lately, the effect of quercetin supplementation (QS) on endurance performance (EP) and maximal oxygen consumption (VO2max) has been receiving much scientific and media attention. Therefore, a meta-analysis was performed to determine QS’s ergogenic value on these variables. Studies were located with database searches (PubMed and SPORTDiscus) and cross-referencing. Outcomes represent mean percentage changes in EP (measured via power output) and VO2max between QS and placebo. Random-effects model meta-regression, mixed-effects model analog to the ANOVA, random-effects weighted mean effect summary, and magnitudebased inferences analyses were used to delineate the effects of QS. Seven research articles (representing 288 subjects) were included, producing 4 VO2max and 10 EP effect estimates. Mean QS daily intake and duration were, respectively, 960 ± 127 mg and 26 ± 24 d for the EP outcome and 1,000 ± 0 mg and 8 ± 23 d for the VO2max outcome. EP was assessed during exercise with a mean duration of 79 ± 82 min. Overall, QS improved EP by 0.74% (95% CI: 0.10–1.39, p = .02) compared with placebo. However, only in untrained individuals (0.83% ± 0.78%, p = .02) did QS significantly improve EP (trained individuals: 0.09% ± 2.15%, p = .92). There was no relationship between QS duration and EP (p = .69). Overall, QS increased VO2max by 1.94% (95% CI: 0.30–3.59, p = .02). Magnitude-based inferences suggest that the effect of QS on EP and VO2max is likely to be trivial for both trained and untrained individuals. In conclusion, this meta-analysis indicates that QS is unlikely to prove ergogenic for aerobic-oriented exercises in trained and untrained individuals.


2021 ◽  
Vol 51 (3) ◽  
pp. 365-375
Author(s):  
Chak Fai Ma ◽  
Sherry Kit Wa Chan ◽  
Yik Ling Chung ◽  
Siu Man Ng ◽  
Christy Lai Ming Hui ◽  
...  

AbstractBackgroundSchizophrenia is a longstanding condition and most patients experience multiple relapse in the course of the condition. High expressed emotion (HEE) has been found to be a predictor of relapse. This meta-analysis and meta-regression examined the association of global EE and relapse specifically focusing on timing of relapse and EE domains.MethodsRandom-effects model was used to pool the effect estimates. Multiple random-effects meta-regression was used to compute the moderator analysis. Putative effect moderators including culture, EE measurements, age, length of condition and study quality were included.ResultsThirty-three prospective cohort studies comprising 2284 patients were included in the descriptive review and 30 studies were included for meta-analysis and meta-regression. Findings revealed that global HEE significantly predicted more on early relapse (⩽12 months) [OR 4.87 (95% CI 3.22–7.36)] than that on late relapse (>12 months) [OR 2.13 (95% CI 1.36–3.35)]. Higher level of critical comments (CC) significantly predicted relapse [OR 2.22 (95% CI 1.16–4.26)], whereas higher level of warmth significantly protected patients from relapse [OR 0.35 (95% CI 0.15–0.85)]. None of the moderators included significantly change the results.ConclusionsThese findings indicate that there is a dynamic interaction between EE-relapse association with time, and CC and warmth are the two important EE domains to influence relapse among patients with schizophrenia. Results also confirmed the foci of family interventions on reducing CC and improving warmth in relationship.


2021 ◽  
pp. 089033442110292
Author(s):  
Mega Hasanul Huda ◽  
Roselyn Chipojola ◽  
Yen Miao Lin ◽  
Gabrielle T. Lee ◽  
Meei-Ling Shyu ◽  
...  

Background Breast engorgement and breast pain are the most common reasons for the early cessation of exclusive breastfeeding by mothers. Research Aims (1) To examine the influence of breastfeeding educational interventions on breast engorgement, breast pain, and exclusive breastfeeding; and (2) to identify effective components for implementing breastfeeding programs. Methods Randomized controlled trials of breastfeeding educational interventions were searched using five English and five Chinese databases. Eligible studies were independently evaluated for methodological quality, and data were extracted by two investigators. In total, 22 trials were identified, and 3,681 participants were included. A random-effects model was used to pool the results, and a subgroup analysis and meta-regression analysis were conducted. Results Breastfeeding education had a significant influence on reducing breast engorgement at postpartum 3 days (odds ratio [OR]: 0.27, 95% CI [0.15, 0.48] p < .001), 4 days (OR: 0.16, 95% CI [0.11, 0.22], p < .001), and 5–7 days (OR: 0.24, 95% CI [0.08, 0.74], p = .013) and breast pain (standardized mean difference: −1.33, 95% CI [−2.26, −0.40]) at postpartum 4–14 days. Participants who received interventions had higher odds of exclusive breastfeeding. Breastfeeding educational interventions provided through lecture combined with skills practical effectively reduced breast engorgement (OR: 0.21; 95% CI [0.15, 0.28]; p = .001) and improved exclusive breastfeeding at postpartum 1–6 weeks (OR: 2.16; 95% CI [1.65, 2.83]; p = .001). Conclusions Breastfeeding educational interventions have been effective in reducing breast engorgement, breast pain, and improved exclusive breastfeeding. A combination of knowledge and skill-based education has been beneficial for sustaining exclusive breastfeeding by mothers.


2021 ◽  
pp. 219256822110308
Author(s):  
Andrew Platt ◽  
Mostafa H. El Dafrawy ◽  
Michael J. Lee ◽  
Martin H. Herman ◽  
Edwin Ramos

Study Design: Systematic review and meta-analysis. Objectives: Indications for surgical decompression of gunshot wounds to the lumbosacral spine are controversial and based on limited data. Methods: A systematic review of literature was conducted to identify studies that directly compare neurologic outcomes following operative and non-operative management of gunshot wounds to the lumbosacral spine. Studies were evaluated for degree of neurologic improvement, complications, and antibiotic usage. An odds ratio and 95% confidence interval were calculated for dichotomous outcomes which were then pooled by random-effects model meta-analysis. Results: Five studies were included that met inclusion criteria. The total rate of neurologic improvement was 72.3% following surgical intervention and 61.7% following non-operative intervention. A random-effects model meta-analysis was carried out which failed to show a statistically significant difference in the rate of neurologic improvement between surgical and non-operative intervention (OR 1.07; 95% CI 0.45, 2.53; P = 0.88). In civilian only studies, a random-effects model meta-analysis failed to show a statistically significant difference in the rate of neurologic improvement between surgical and non-operative intervention (OR 0.75; 95% CI 0.21, 2.72; P = 0.66). Meta-analysis further failed to show a statistically significant difference in the rate of neurologic improvement between patients with either complete (OR 4.13; 95% CI 0.55, 30.80; P = 0.17) or incomplete (OR 0.38; 95% CI 0.10, 1.52; P = 0.17) neurologic injuries who underwent surgical and non-operative intervention. There were no significant differences in the number of infections and other complications between patients who underwent surgical and non-operative intervention. Conclusions: There were no statistically significant differences in the rate of neurologic improvement between those who underwent surgical or non-operative intervention. Further research is necessary to determine if surgical intervention for gunshot wounds to the lumbosacral spine, including in the case of retained bullet within the spinal canal, is efficacious.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
P Ioannidou ◽  
J Bosdou ◽  
D Papanikolaou ◽  
D Goulis ◽  
A Lambropoulos ◽  
...  

Abstract Study question Does oral antioxidant supplementation improve sperm quality in infertile men with varicocele who have not undergone surgical repair? Summary answer Oral antioxidant supplementation improves sperm concentration and motility in infertile men with varicocele who have not undergone surgical repair. What is known already: Benefit from oral antioxidant supplementation has been shown in infertile men with varicocele following surgical repair. Similarly, oral antioxidant supplementation has been suggested in infertile men with varicocele who have not undergone surgical repair. However, its effect currently remains controversial. Study design, size, duration A literature search was performed until January 2021 aiming to identify prospective studies evaluating the use of oral antioxidant supplementation alone or in combination in men with varicocele who have not undergone surgical repair. Participants/materials, setting, methods Seven prospective studies were identified, published between 1987 and 2018, including 278 infertile men with varicocele who had not undergone surgical repair. The number of patients included ranged from 20 to 65. Sperm analysis, evaluating sperm concentration, motility and morphology was performed in these studies before and after oral antioxidant supplementation. Meta-analysis of weighted data was performed using random effects model. Results are reported as weighted mean difference (WMD) with 95% confidence interval (CI). Main results and the role of chance Seven studies were included in the systematic review. Oral antioxidant supplementation was performed by a combination of pentoxifylline, zinc and folic acid (single study), a combination of l-carnitine, fumarate, acetyl-l-carnitine, fructose, CoQ, vitamin C, zinc, folic acid and vitamin B12 (single study), a combination of L-Carnitine, vitamin C, coenzyme Q10, vitamin E, vitamin B9, vitamin B12, zinc , and selenium, l-carnitine (single study), or sole treatment with acetyl-l-carnitine (single study), L-Carnitine (single study), Coenzyme Q10 (single study) or zinc sulfate (single study). For the purpose of meta-analysis, the effect of oral antioxidant supplementation was evaluated after three months of treatment. Oral antioxidant supplementation significantly increased sperm concentration (WMD +5.65x106/ml 95% CI: +1.11 to + 10.12 p = 0.01, random effects model) and motility (WMD +4.30%, 95% CI: +0.86 to + 7.74 p = 0.01, random effects model) in infertile men with varicocele who had not undergone surgical repair. On the other hand, no significance difference was observed in sperm morphology (WMD +3.9%, 95% CI: –0.16 to + 8.04 p = 0.06, random effects model) and volume (WMD +0.53ml, 95% CI: 0.0 to + 1.0 p = 0.052, random effects model). Limitations, reasons for caution The number of relevant trials and that of patients included is small to allow for solid conclusions to be drawn. Moreover, although different oral antioxidants have been administered in infertile who had not undergone surgical repair, subgroup analysis was not feasible. Wider implications of the findings: Currently, limited evidence supports the use of oral antioxidants in the treatment of men with varicocele, who have not undergone surgical repair. Although the benefit in sperm concentration and motility appears to be modest, it might be important regarding achievement of pregnancy in these men. Trial registration number Not applicable


Cephalalgia ◽  
2014 ◽  
Vol 35 (1) ◽  
pp. 63-72 ◽  
Author(s):  
Amy A Gelfand ◽  
Peter J Goadsby ◽  
I Elaine Allen

Context Infant colic is a common and distressing disorder of early infancy. Its etiology is unknown, making treatment challenging. Several articles have suggested a link to migraine. Objective The objective of this article was to perform a systematic review and, if appropriate, a meta-analysis of the studies on the relationship between infant colic and migraine. Data sources Studies were identified by searching PubMed and ScienceDirect and by hand-searching references and conference proceedings. Study selection For the primary analysis, studies specifically designed to measure the association between colic and migraine were included. For the secondary analysis, studies that collected data on colic and migraine but were designed for another primary research question were also included. Data extraction Data were abstracted from the original studies, through communication with study authors, or both. Two authors independently abstracted data. Main outcomes and measures The main outcome measure was the association between infant colic and migraine using both a fixed-effects model and a more conservative random-effects model. Results Three studies were included in the primary analysis; the odds ratio for the association between migraine and infant colic was 6.5 (4.6–8.9, p < 0.001) for the fixed-effects model and 5.6 (3.3–9.5, p = 0.004) for the random-effects model. In a sensitivity analysis wherein the study with the largest effect size was removed, the odds ratio was 3.6 (95% CI 1.7–7.6, p = 0.001) for both the fixed-effects model and random-effects model. Conclusions In this meta-analysis, infant colic was associated with increased odds of migraine. If infant colic is a migrainous disorder, this would have important implications for treatment. The main limitation of this meta-analysis was the relatively small number of studies included.


Diagnostics ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1665
Author(s):  
Dong Hwan Kim ◽  
Sang Hyun Choi ◽  
Ju Hyun Shim ◽  
So Yeon Kim ◽  
Seung Soo Lee ◽  
...  

Our meta-analysis aimed to evaluate the diagnostic performance of surveillance magnetic resonance imaging (sMRI) for detecting hepatocellular carcinoma (HCC), and to compare the diagnostic performance of sMRI between different protocols. Original articles about the diagnostic accuracy of sMRI for detecting HCC were found in major databases. The meta-analytic pooled sensitivity and specificity of sMRI for detecting HCC were determined using a bivariate random effects model. The pooled sensitivity and specificity of full MRI and abbreviated MRI protocols were compared using bivariate meta-regression. In the total seven included studies (1830 patients), the pooled sensitivity of sMRI for any-stage HCC and very early-stage HCC were 85% (95% confidence interval, 79–90%; I2 = 0%) and 77% (66–85%; I2 = 32%), respectively. The pooled specificity for any-stage HCC and very early-stage HCC were 94% (90–97%; I2 = 94%) and 94% (88–97%; I2 = 96%), respectively. The pooled sensitivity and specificity of abbreviated MRI protocols were 87% (80–94%) and 94% (90–98%), values that were comparable with those of full MRI protocols (84% [76–91%] and 94% [89–99%]; p = 0.83). In conclusion, sMRI had good sensitivity for detecting HCC, particularly very early-stage HCC. Abbreviated MRI protocols for HCC surveillance had comparable diagnostic performance to full MRI protocols.


Author(s):  
Getenet Dessie ◽  
Henok Mulugeta ◽  
Desalegne Amare ◽  
Ayenew Negesse ◽  
Fasil Wagnew ◽  
...  

Abstract Background Despite the high prevalence of diabetes in Africa, the extent of undiagnosed diabetes in the region is still poorly understood. This systematic review and meta-analysis was designed to determine the pooled prevalence of undiagnosed diabetes mellitus among adults in Africa. Methods We conducted a systematic desk review and electronic web-based search of PubMed, Google Scholar, EMBASE, and the World Health Organization’s Hinari portal (which includes the SCOPUS, African Index Medicus, and African Journals Online databases), identifying peer-reviewed research studies on the prevalence of undiagnosed diabetes among adult individuals using pre-defined quality and inclusion criteria. We ran our search from June 1, 2018 to Jun 14, 2020. We extracted relevant data and presented descriptive summaries of the studies in tabular form. The I2 test was used to assess heterogeneity across studies. A random effects model was used to estimate the pooled prevalence of undiagnosed diabetes mellitus at a 95% confidence interval (CI). Funnel plot asymmetry and Egger’s tests were used to check for publication bias. The final effect size was determined by applying a trim and fill analysis in a random-effects model. Results Our search identified 1442 studies amongst which 23 articles were eligible for inclusion in the final meta-analysis. The average pooled prevalence of undiagnosed diabetes mellitus among adults was 3.85 (95% CI: 3.10–4.60). The pooled prevalence of undiagnosed diabetes mellitus based on geographic location was 4.43 (95% CI: 3.12–5.74) in Eastern Africa; 4.72 (95% CI: 2.64–6.80) in Western Africa; 4.27 (95% CI: 1.77–6.76) in Northern Africa and 1.46 (95%CI: 0.57–2.34) in southern Africa respectively. Conclusion Our findings indicate a high prevalence of undiagnosed diabetes in Africa and suggest that it may be more prevalent in Western Africa than the rest of the regions. Given the high levels of undiagnosed diabetes in the Africa region, more attention should be paid to incorporating diabetes screening and treatment services into existing diabetes related programs to reduce the prevalence of undiagnosed cases.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Dawood Aghamohammadi ◽  
Neda Dolatkhah ◽  
Fahimeh Bakhtiari ◽  
Fariba Eslamian ◽  
Maryam Hashemian

AbstractThis study designed to evaluate the effect of nutraceutical supplementation on pain intensity and physical function in patients with knee/hip OA. The MEDLINE, Web of Science, Cochrane Library, Scopus, EMBASE, Google Scholar, Science direct, and ProQuest in addition to SID, Magiran, and Iranmedex were searched up to March 2020. Records (n = 465) were screened via the PICOS criteria: participants were patients with hip or knee OA; intervention was different nutritional supplements; comparator was any comparator; the outcome was pain intensity (Visual analogue scale [VAS]) and physical function (Western Ontario and McMaster Universities Arthritis [WOMAC] index); study type was randomized controlled trials. The random effects model was used to pool the calculated effect sizes. The standardized mean difference (SMD) of the outcome changes was considered as the effect size. The random effects model was used to combine the effect sizes. Heterogeneity between studies was assessed by Cochran's (Q) and I2 statistics. A total of 42 RCTs were involved in the meta-analysis. Nutritional supplementation were found to improve total WOMAC index (SMD = − 0.23, 95% CI − 0.37 to − 0.08), WOMAC pain (SMD = − 0.36, 95% CI − 0.62 to − 0.10) and WOMAC stiffness (SMD = − 0.47, 95% CI − 0.71 to − 0.23) subscales and VAS (SMD = − 0.79, 95% CI − 1.05 to − 0.05). Results of subgroup analysis according to the supplementation duration showed that the pooled effect size in studies with < 10 months, 10–20 months and > 20 months supplementation duration were 0.05, 0.27, and 0.36, respectively for WOMAC total score, 0.14, 0.55 and 0.05, respectively for WOAMC pain subscale, 0.59, 0.47 and 0.41, respectively for WOMAC stiffness subscale, 0.05, 0.57 and 0.53, respectively for WOMAC physical function subscale and 0.65, 0.99 and 0.12, respectively for VAS pain. The result suggested that nutraceutical supplementation of patients with knee/hip OA may lead to an improvement in pain intensity and physical function.


2020 ◽  
pp. 019459982095117
Author(s):  
Craig A. Bollig ◽  
David S. Lee ◽  
Angela L. Mazul ◽  
Katelyn Stepan ◽  
Sidharth V. Puram ◽  
...  

Objective To systematically review the literature to determine the prevalence and clinical outcomes of second primary oropharyngeal squamous cell carcinoma (OPSCC). Data Sources Search strategies created with a medical librarian were implemented using multiple databases in October 2019. Review Methods The population of interest included adults age >18 years with a p16+ or human papillomavirus-positive OPSCC. The outcome was a synchronous or metachronous second primary OPSCC. Inclusion and exclusion criteria were designed to capture all study designs. In total, 685 records were identified by the search strategy. Two reviewers independently performed the review, extracted data, and performed a quality assessment. Primary Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. A random-effects model was used for the meta-analysis. Results A total of 2470 patients with 35 second primary OPSCCs from 15 studies were identified. The pooled prevalence of second primary OPSCC was 1.4% (range, 0%-14.3%). In the random-effects model, the prevalence was estimated at 1.3% (95% CI, 0.7%-2.3%; P = .51, I2 = 52%). Of the 30 patients with treatment information, 26 (86.7%) received surgical treatment, while 4 (13.3%) underwent nonsurgical therapy. Of the 29 patients with available survival information, 22 (75.9%) had no evidence of disease at last follow-up, 5 (17.2%) ultimately died of disease, and 2 (6.9%) were alive with disease. Conclusion Overall, the rate of second primary OPSCC in patients with an index p16+ OPSCC is low, and most patients are successfully treated. Insufficient evidence currently exists to recommend routine elective tonsillectomy during surgical treatment of p16+ OPSCC.


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