Safety and efficacy of stem cell therapy: an overview protocol on published meta-analyses and evidence mapping

Reporting and methodological quality of systematic reviews of DPP-4 inhibitors for patients with type 2 diabetes mellitus: an evidence-based mapping

AIMS

To evaluate the reporting and methodological quality of relevant systematic reviews (SRs) and meta-analyses (MAs) on Dipeptidyl peptidase-4 inhibitors (DPP-4I) for Type 2 diabetes mellitus (T2DM).

METHODS

Relevant SRs and MAs on T2DM and DPP-4I published between 2017 and November 2021 were retrieved from PubMed, Embase, Cochrane Library, Web of Science, VIP, CNKI, CBM, and WanFang databases. Two independent reviewers performed the search, selection, and data extraction. The reporting and methodological quality of the reviewers was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR 2) tools. The relationship between reporting and methodological quality score was assessed with the Spearman correlation test.

RESULTS

Twenty-one studies involving 151,715 participants were included in the study. This overview showed that DPP-4I was safer and more efficacious than other anti-hyperglycemic drugs (OADs) in treating T2DM. The methodological quality of one SR was low, while the rest were very low. Thus, refinements are needed in the quality of protocol and registration information, a complete search strategy, the summary of the evidence, the listing of excluded studies, assessing the potential impact of risk of bias in RCTs, and discussing the RoB on MA results, and the funding of RCTs need improvement for generating SR. In addition, the reporting and methodological quality scores were moderately correlated (r_S = 0.66, P = 0.001).

CONCLUSIONS

DPP-4I is safer and more efficacious than OADs in treating T2DM. However, the reporting and methodological quality of the related SRs was unsatisfactory. Therefore, PRISMA and AMSTAR 2 analyses should be followed to enhance the overall quality of future SRs.

Reporting and methodological quality of meta-analyses of acupuncture for patients with migraine: A methodological investigation with evidence map

BACKGROUND

Acupuncture has been widely used to relieve migraine-related symptoms. However, the findings of previous systematic reviews (SRs) and meta-analyses (MAs) are still not completely consistent. Their quality is also unknown, so a comprehensive study is needed.

OBJECTIVE

To evaluate the reporting and methodological quality of these MAs concerning acupuncture for migraine, and summarize evidence about the efficacy and safety of acupuncture for migraine.

SEARCH STRATEGY

PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, Chinese Biomedical Databases, Wanfang Data, and VIP databases were searched from inception to September 2020, with a comprehensive search strategy.

INCLUSION CRITERIA

The pairwise MAs of randomized controlled trials (RCTs) concerning migraine treated by acupuncture or acupuncture-based therapies, with a control group that received sham acupuncture, medication, no treatment, or acupuncture at different acupoints were included.

DATA EXTRACTION AND ANALYSIS

Two independent investigators screened studies, extracted relevant data, and assessed reporting and methodological quality using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2009 and A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2), then all results were cross-checked. Spearman correlation test was used to evaluate the correlation between reporting and methodological quality scores.

RESULTS

A total of 20 MAs were included in this study. The included MAs indicated that acupuncture was efficacious and safe in preventing and treating migraine when compared with control intervention. There was a high correlation between reporting and methodological quality scores (r_s = 0.87, P < 0.001). The quality of the included SRs needs to be improved mainly with regard to protocol and prospective registration, using a comprehensive search strategy, summarizing the strength of evidence body for key outcomes, a full list of excluded studies with reasons for exclusion, reporting of RCTs' funding sources, and assessing the potential impact of risk of bias in RCTs on MA results.

CONCLUSION

Acupuncture is an effective and safe intervention for preventing and treating migraine, and could be considered as a good option for patients with migraine. However, the reporting and methodological quality of MAs included in this overview is suboptimal. In the future, AMSTAR 2 and PRISMA tools should be followed when making and reporting an SR with MA.

Chinese Medicine as an Adjunctive Treatment for Gastric Cancer: Methodological Investigation of meta-Analyses and Evidence Map

Background: Many meta-analyses (MAs) on Chinese medicine (CM) as an adjunctive treatment for gastric cancer have been published in recent years. However, the pooled evidence reported in MAs and their methodological quality remain unknown. Therefore, we designed a study to comprehensively evaluate and summarize the current evidence of CMs for gastric cancer in published MAs.

Methods: A systematic search on MAs published in English from inception to 1st September 2021 was conducted in PubMed and Embase. The AMSTAR-2 tool was used to evaluate the methodological quality of the included MAs, and the results of the quality assessment were visualized using the evidence mapping method. Stata 17/SE was used for statistical analysis (Registration number: INPLASY202190005).

Results: A total of 20 MAs (16 pairwise and 4 network MAs) were included from 118 records. These MAs were published in 14 journals from 2013 to 2021, with the number of patients and trials ranging from 688 to 6,857, and from 10 to 85, respectively. A large number of CMs (e.g., AiDi, FuFangKuShen, and HuaChanSu) in combination with chemotherapy for gastric cancer were identified among the included MAs. According to the pooled results reported in MAs, when compared to chemotherapy alone, CMs in combination with chemotherapy not only improve various outcomes on efficacy (e.g., objective response rate, quality of life) but also reduce various adverse reactions (e.g., leucopenia, nausea and vomiting). Only 2 MAs were low in terms of the overall methodological quality, while the other 18 MAs were all critically low. The methodology was required to be advanced significantly, mainly involving: study protocol and registration, explanation for the inclusion of study design, list of excluded studies with justifications, adequate details of included studies, reporting on funding sources of primary studies, and evaluation of the potential impact of risk of bias. In addition, MAs that received funds support (β = 2.68; 95%CI: 0.40 to 4.96; p = 0.024) or were published in journals with higher impact factor (β = 2.81; 95%CI: 0.69 to 4.92; p = 0.012) had a higher score on the overall methodological quality in the univariate analysis, but the results were not statistically significant according to the multivariate analysis.

Conclusion: Combining CMs with chemotherapy can potentially improve clinical outcomes and reduce the relevant adverse effects in patients with gastric cancer. However, the methodological quality of relevant MAs requires significant improvement, and the current evidence needs to be validated through multinational trials that are well-designed and have a large sample size.

Saffron (Crocus sativus L.) and health outcomes: a meta-research review of meta-analyses and an evidence mapping study

BACKGROUND

Although a number of systematic reviews and meta-analyses of saffron (Crocus sativus L.) have been published, no study has comprehensively summarized the clinical evidence from meta-analyses, or assessed the reporting or methodological quality of these reviews.

PURPOSE

The present meta-research study was designed to fill the gaps in knowledge to inform future studies and allow enhanced clinical decision-making on saffron.

METHODS

The PubMed, Cochrane Library, Embase, and CNKI databases were systematically searched from inception to April 3 rd, 2021, for meta-analyses of clinical trials that assessed the efficacy and safety of saffron. PRISMA 2009 and AMSTAR-2 were employed to assess the reporting and methodological quality of meta-analyses identified in the search, respectively. The present study was registered on PROSPERO with registration number CRD42020220274.

RESULTS

Nineteen eligible systematic reviews with meta-analyses published in English were identified from 235 records. These meta-analyses were published in 12 peer-reviewed journals from 2013 to 2021. The heterogeneous results indicated that saffron significantly reduced fasting blood glucose, waist circumference, diastolic blood pressure, concentrations of total cholesterol and low-density lipoprotein cholesterol, and improved symptoms of depression, cognitive function and sexual dysfunction compared with controls (mainly placebos). Common side effects of saffron consumption included nausea, dry mouth, poor appetite, and headache, but no serious adverse reactions were reported. Primary analysis and sensitivity analysis confirmed that the reporting and methodological quality of reviews included in the study were highly correlated (p < 0.001). The quality of meta-analyses of saffron requires improvement by including a structured abstract, a prospective protocol and registration, explanation of the study designs within each study that is reviewed, the searches, risk of bias assessment, literature selection, and reporting of funding sources.

CONCLUSION

The available evidence indicates that saffron is a safe plant for administration as a medicine and can improve diverse clinical outcomes, but the scientific quality of the published systematic reviews needs to be improved. Moreover, the clinical effects of saffron need to be confirmed through high-quality randomized trials in multiple countries with large sample sizes.

Therapeutic Effects of Stem Cells From Different Source on Renal Ischemia- Reperfusion Injury: A Systematic Review and Network Meta-analysis of Animal Studies

Objective: Although stem cell therapy for renal ischemia-reperfusion injury (RIRI) has made immense progress in animal studies, conflicting results have been reported by the investigators. Therefore, we aimed to systematically evaluate the effects of different stem cells on renal function of animals with ischemia-reperfusion injury and to compare the efficacies of stem cells from various sources. Methods: PubMed, Web of Science, Embase, Cochrane, CNKI, VIP, CBM, and WanFang Data were searched for records until April 2021. Two researchers independently conducted literature screening, data extraction, and literature quality evaluation. Results and conclusion: Seventy-two animal studies were included for data analysis. Different stem cells significantly reduced serum creatinine and blood urea nitrogen levels in the early and middle stages (1 and 7 days) compared to the negative control group, however there was no significant difference in the late stage among all groups (14 days); In the early stage (1 day), the renal histopathological score in the stem cell group was significantly lower than that in the negative control group, and there was no significant difference among these stem cells. In addition, there was no significant difference between stem cell and negative control in proliferation of resident cells, however, significantly less apoptosis of resident cells than negative control. In conclusion, the results showed that stem cells from diverse sources could improve the renal function of RIRI animals. ADMSCs and MDMSCs were the most-researched stem cells, and they possibly hold the highest therapeutic potential. However, the quality of evidence included in this study is low, and there are many risks of bias. The exact efficacy of the stem cells and the requirement for further clinical studies remain unclear.

Nonpharmacological interventions for cancer-related fatigue in lung cancer patients: A protocol for an evidence map of overview of a network meta-analysis of existing trials

BACKGROUND

Lung cancer is one of the most common cancers, the symptoms and treatment of which can cause negative emotions like anxiety, depression, and cancer-related fatigue (CRF). Nonpharmacological interventions, serving as alternative therapies, can greatly alleviate CRF in lung cancer patients. Previous meta-analyses have reported nonpharmacological interventions of CRF in lung cancer patients, but the results may be conflicting, and the reporting and methodological qualities remain unknown. Moreover, there is limited evidence to identify efficient and safe non-pharmacological interventions of CRF in lung cancer patients. This study aims to assess the therapeutic efficacy of nonpharmacological interventions of CRF in lung cancer patients through a network meta-analysis.

METHODS

Relevant literatures reporting non-pharmacological interventions of CRF in lung cancer patients published before June 2021 will be searched in online databases, including Wanfang, VP Information Chinese Journal Service Platform, China National Knowledge Infrastructure, Chinese BioMedicine Literature Database, PubMed, Embase, Cochrane, and Web of science. Two reviewers will be independently responsible for study selection, quality appraisal, and data extraction. Data analysis will be performed using the STATA14.0 and GEMTC 0.14.3 software.

RESULTS

This meta-analysis will provide additional and stronger evidences for nonpharmacological interventions of CRF in lung cancer patients. Our findings will be conductive to make therapeutic decisions by clinicians.

CONCLUSION

This study will provide a reliable evidence-based basis for non-pharmacological interventions of CRF in lung cancer patients.

ETHICS AND DISSEMINATION

Ethical approval was not required for this study. The systematic review will be published in a peer-reviewed journal, presented at conferences, and shared on social media platforms. This review would be disseminated in a peer-reviewed journal or conference presentations.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/QRY42.

Pharmacological and non-pharmacological interventions for osteoporosis: A protocol for an overview with an evidence map and a network meta-analysis of trials

BACKGROUND

Osteoporosis is a common bone disease that has a significant social and economic effect. Many meta-analyses of pharmacological and non-pharmacological treatments for osteoporosis have been reported, but the findings may be contradictory, and both the reporting and methodological quality remain unknown. As a result, an overview that includes a network meta-analysis was proposed to address these issues.

METHODS

The Cochrane library, PubMed, Embase, CBM, and CNKI databases will be systematically searched for meta-analyses of osteoporosis interventions from inception to May 2021. In order to evaluate the reporting and methodological quality of each included meta-analysis, Preferred Reporting Items for Systematic Review and Meta-analysis 2020 (PRISMA-2020), and A MeaSurement Tool to Assess systematic Reviews 2 (AMSTAR-2) will be used. For the assessment of the relative efficacy and safety of treatments reported in the randomized controlled trials included in the meta-analyses identified by the overview, a Bayesian network meta-analysis will be carried out. The odds ratio and standard mean difference with their 95% credible intervals will be used to present the binary and continuous outcomes, respectively, and the Grading of Recommendations Assessment, Development and Evaluation method will be used to determine the certainty of the evidence through Confidence In Network Meta-Analysis. Data analysis will be performed using WinBUGS, R, and Stata, with a 2-sided P < .05 considered as statistically significant.

RESULTS

The findings of this overview, which includes a network meta-analysis, will be submitted to a peer-reviewed journal for publication.

CONCLUSION

An overview with network meta-analysis will provide evidence on the efficacy and safety of pharmacological and non-pharmacological interventions for osteoporosis, while also identifying the flaws in previously published meta-analyses. All of these results may be used to improve clinical decision-making and future studies.

INPLASY REGISTRATION NUMBER

INPLASY202150022.