While the macronutrient content of a ketogenic diet specifically utilized for childhood epilepsy is clearly defined in the literature, variations among other ketogenic diets exhibit substantial heterogeneity. Furthermore, studies utilizing ketogenic diets contain several confounders with notable impacts on outcomes, thereby rendering both their findings and those of the meta-analyses less reliable. The objective of this meta-epidemiological assessment was to scrutinize existing clinical trials that investigated the effects of ketogenic diets on patients with obesity and diabetes, thereby determining the feasibility of conducting a meta-analysis. The Ovid Medline, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), and Embase databases were searched from 1946 to 24 September 2024. Of the studies reviewed, none met the predefined inclusion criteria. However, seven articles met these criteria very closely. In the future, studies investigating the effects of ketogenic diets containing significant confounding factors should adopt a single definition of a ketogenic diet. Additionally, accurate measurement of actual macronutrient and caloric intake, along with regularly monitored nutritional ketosis, will be essential to highlight the true effects of a ketogenic diet.

Background: Gastrointestinal (GI) cancers, particularly colorectal, gastric, and liver cancers, account for a major global burden of incidence and mortality and remain important targets for genetic susceptibility research. Long non-coding RNAs (lncRNAs) can regulate gene expression and are increasingly studied in carcinogenesis. Numerous case–control studies have investigated associations between lncRNA polymorphisms and cancer risk, but findings are inconsistent. This study systematically evaluated the association between lncRNA single nucleotide polymorphisms (SNPs) and GI cancer susceptibility. Methods: A systematic literature search from Embase, Medline, Scopus, and Web of Science databases identified 174 potentially extractable studies. Eligible studies were case–control or cross-sectional studies published up to 8 May 2026; case reports, reviews, and meta-analyses were excluded. After screening for identical cancer type, identical SNP, and sufficient statistical data, only variants supported by at least three independent case–control studies were eligible for meta-analysis. Seven SNPs across six lncRNAs, comprising 23 studies (15,131 cases and 20,969 controls), were selected. Because of the limited number of eligible studies, subgroup analyses could not be performed consistently. Odds ratios (ORs) with 95% confidence intervals (CIs) were assessed under allelic, dominant, and recessive genetic models using fixed- or random-effects models according to heterogeneity. Results: In the primary analyses restricted to homogenous Chinese populations, H19 rs3024270 was significantly associated with hepatocellular carcinoma under allelic (OR = 1.22, 95% CI: 1.05–1.42, p = 0.01) and dominant models (OR = 1.22, 95% CI: 1.03–1.45, p = 0.02). Exploratory analyses including mixed populations identified additional associations, with the strongest observed for MEG3 rs7158663 and colorectal cancer, showing significant risk elevation under allelic (OR = 1.42, 95% CI: 1.25–1.63, p < 0.00001), dominant (OR = 1.42, 95% CI: 1.20–1.68, p < 0.0001), and recessive models (OR = 1.98, 95% CI: 1.46–2.68, p < 0.0001). PRNCR1 rs16901946 showed a significant association with gastric cancer under the dominant model (OR = 1.20, 95% CI: 1.02–1.41, p = 0.03), while GAS5 rs145204276 demonstrated a recessive-model association with gastric cancer (OR = 1.30, 95% CI: 1.16–1.46, p < 0.0001). In contrast, GAS5 rs145204276 in colorectal cancer; H19 rs2839698 and MALAT1 rs619586 in hepatocellular carcinoma yielded heterogeneous or unstable pooled estimates. Findings should be interpreted cautiously due to the limited number of studies, heterogeneity, and potential publication bias. Conclusions: Among the primary analyses, H19 rs3024270 showed the most consistent association with HCC susceptibility. Exploratory analyses identified candidate variants, including MEG3 rs7158663, PRNCR1 rs16901946, and GAS5 rs145204276. Population-specific effects and study heterogeneity remain important limitations. PROSPERO registration number for this study: CRD42023389742.

Introduction Randomised controlled trials (RCTs) are considered the gold standard for evaluating the efficacy and safety of healthcare interventions. For valid systematic reviews and evidence-based clinical guidelines, it is essential that results of all eligible RCTs are accessible. However, articles about trials published in languages other than English are often not listed in well-known and open trial databases like Medline and therefore scarcely findable. Handsearching national journals is an important approach to identify these articles and enhance their global visibility. Consequently, the results of trials conducted and published in non-English-speaking countries are not lost but rather integrated into the global body of evidence. The present study aims to evaluate the benefits of extensive handsearching in Hungary and to identify key medical fields for future efforts. We will also assess the extent of grey literature in Hungary. We will appraise the risk of bias in the identified RCTs and controlled clinical trials (CCTs; indicating quasi-randomised or possibly randomised controlled trials) and examine the reporting quality of articles in Hungarian medical journals. Additionally, we will explore whether the automation tool Paperfetcher, recommended by Cochrane for handsearching, can effectively support these efforts in a non-English language context. Methods and analysis We will conduct a cover-to-cover handsearch of all Hungarian medical journals publishing content in the year 2023 to identify all controlled clinical trials, including RCTs, CCTs and non-RCTs, which are trials that use a clearly non-random method for allocating participants to groups. We will also search conference proceedings submitted to the Hungarian National Széchényi Library, abstract supplements from journals available via the Hungarian Medical Bibliography database, preprints available on medRxiv, Hungarian theses and dissertations, as well as Google Scholar to identify grey literature. Two independent researchers will screen the identified records, assess their eligibility, extract data and evaluate the risk of bias and reporting quality according to the CONSORT statement. To verify the availability of reports and publications derived from the identified trials in electronic databases, we will systematically search MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL), Embase and Scopus. All identified RCTs and CCTs not yet included in CENTRAL will be added to the database. Additionally, we will compare handsearching supported by the Paperfetcher tool with unsupported handsearching to evaluate the tool’s effectiveness in a Hungarian language context. Ethics and dissemination Since the publication resulting from the handsearching activity is a retrospective review of publicly available sources of evidence, ethical approval is not required. The study findings will be submitted for publication in a peer-reviewed journal and will be presented at international conferences.

Introduction: Dietary recommendations should be based on scientific evidence, and ideally, systematic reviews (SRs) are conducted as part of the guideline development process. The usability of SRs for decision-making is primarily determined by the quality of the evidence from available primary studies, as well as the quality of the SRs themselves. A comprehensive SR protocol ensures high-quality implementation and minimises bias, while making these protocols publicly accessible, promotes transparency and prevents redundancy. The PROSPERO database offers valuable insights into planned methodologies. The aim of this study is to investigate the completeness of reporting in SR protocols for diet- or nutrition-related trials, determine how this has changed over time, and examine the publication of completed SRs by comparing their content with those described in the corresponding protocols. Methods and analysis: We developed a systematic search strategy for PROSPERO to identify nutrition- or diet-related SR protocols registered at two different time points (2019 and 2024). Following a screening process to identify eligible protocols, relevant predefined data will be extracted. Subsequently, a structured search will be conducted to identify potential journal publications of the selected protocols, as well as publications describing the results of the SRs, from which relevant predefined data will be also extracted. The methodology of the published articles will be compared with the corresponding a priori protocols registered in PROSPERO. The PROSPERO records registered in 2019 will be compared with those registered in 2024. The results will be evaluated by descriptive statistics, the reporting completeness of PROSPERO records will be assessed based on Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRISMA-P), the planned use of any approaches to assess certainty of evidence will be investigated, and the adherence of published SRs to the methodological details outlined in their corresponding PROSPERO entries will be examined. Ethics and dissemination: Since both databases and publications used in this study are publicly available, ethical approval is not required. Results of the study will be submitted for publication in an international, peer-reviewed journal. PROSPERO registration number: The present study has previously been registered with the Open Science Framework ( https://osf.io/8fsx7 ).

Background/Objectives: Nutrition plays a core role in chronic disease management, and there is growing interest in the health impact of plant-based diets (PBDs) in people with overweight or obesity. We conducted this systematic review and meta-analysis to summarize the evidence on the health effect of PBDs compared to omnivorous diets in overweight or obese individuals. Methods: We searched the databases Cochrane Central Register of Controlled Trials, MEDLINE, Embase, ClinicalTrials.gov and WHO International Clinical Trials Registry Platform from inception to 3 January 2024. Two review authors independently screened studies for eligibility, extracted data, evaluated the risk of bias, and rated the certainty of the evidence using GRADE. This study is registered with PROSPERO, CRD42021225525. We used random-effects meta-analysis to analyze data. Results: Of 2664 records identified, 10 randomized controlled trials (RCTs) and six ongoing studies met the inclusion criteria. The available evidence suggests little to no difference between plant-based and omnivorous diets for body weight, systolic blood pressure, diastolic blood pressure, serum glucose, serum insulin, insulin sensitivity, total cholesterol, triglyceride, HDL cholesterol and body fat mass. Plant-based diets may slightly reduce LDL cholesterol. They may also reduce BMI and HbA1c, although the certainty of the evidence is very low. Longer-duration dietary interventions (14 weeks or more) showed greater improvements in BMI, LDL cholesterol and HbA1c. Conclusions: Plant-based diets may represent a dietary option for people with overweight or obesity and may support modest improvements in selected cardiometabolic outcomes, although the available evidence is limited and uncertain. Most outcomes showed little or no difference between PBDs and comparison diets, while the observed effects on BMI and HbA1c were supported by very low certainty evidence.

Introduction Prehospital emergency care (PEC) requires rapid evidence-based decisions to maximise the effectiveness of care and to improve clinical outcomes. There are multiple challenges related to clinical research performed in the PEC setting. The aim of our study is to systematically review and assess the characteristics, quality of reporting, risk of bias and pragmatism in recent PEC trials, thereby identifying potential gaps and strengths that can guide the design of future prehospital studies. Methods and analysis We will systematically search databases MEDLINE, Embase and Cochrane CENTRAL to identify all randomised controlled trials conducted in the field of PEC and published in English language between 2010 and 2024. No restrictions will be made to the participants, interventions and outcomes. Risk of bias will be evaluated using the Cochrane Risk of Bias 2 tool. The level of pragmatism will be assessed using the Pragmatic-Explanatory Continuum Indicator Summary-2 score. Exploratory data analysis will be used to investigate and summarise main patterns. Differences in characteristics between PEC fields, study designs, publication year and associations between pragmatism levels, risk of bias and quality of reporting will be the primary focus. Ethics and dissemination There are no ethical concerns directly relevant to this review. This study has been previously registered with the Open Science Framework (osf.io/rzn9j). The manuscript will be submitted for publication to a relevant, peer-reviewed journal.