Methodological Quality Of Clinical Trials Research Articles

Methodological Quality of Clinical Trials in Amyotrophic Lateral Sclerosis: A systematic Review.

More than 200 clinical trials have been performed worldwide in ALS so far, but no agents with substantial efficacy on disease progression have been found. To describe the methodological quality of all clinical trials performed in ALS and published before December 31, 2022. We conducted a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta Analyses. 213 trials were included. 47.4% manuscripts described preclinical study evaluation, with a positive effect in all. 67.6% of trials were conducted with a parallel-arm design, while 12.7% were cross-over studies; 77% were randomized, while in 5.6% historical-controls were used for comparison. 70% of trials were double blind. Participant inclusion allowed forced vital capacity (or corresponding slow vital capacity)<50% in 15% cases, between 55-65% in 21.6%, between 70-80% in 14.1% reports, and 49.3% of the evaluated manuscripts did not provide a minimum value for respiratory capacity at inclusion. Disease duration was < 6-months in 6 studies, 7-36 months in 68, 37-60 months in 24, 8 trials requested more than 1-month of disease duration, while in 107 reports a disease duration was not described. Dropout rate was ≥20% in 30.5% trials, while it was not reported for 8.5% . The methodological quality of the included studies was highly variable. Major issues to be addressed in future ALS clinical trials include: the requirement for standard animal toxicology and phase I studies, the resource-intensive nature of phase II-III studies, adequate study methodology and design, a good results reporting.

Methodological quality of clinical trials of keloid scars

Methodological quality of clinical trials of keloid scars

Bicruciate-Retaining Total Knee Arthroplasty: State of the Art for the Younger and Active Population? A Systematic Review and Future Prospective

(1) Background: Total knee arthroplasty (TKA) is a well-established surgical treatment for end-stage osteoarthritis. While no leading factor can be identified, the high frequency of patient dissatisfaction (20%) pertains to several key features such as preoperative expectations and postoperative improvement in knee function. Bicruciate-retaining total knee arthroplasty (BCR-TKA) may improve kinematics and lead to improved clinical outcome in the higher-demanding patients. (2) Methods: A systematic review of the literature was performed to assess the best available preclinical and clinical literature on BCR-TKA for kinematics and clinical outcome and adverse events such as implant loosening. Articles were screened using predefined in- and exclusion criteria. The guidelines for Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) were used. (3) Results: The literature search resulted in 352 articles which were screened for title and abstract. After application of the in- and exclusion criteria, 13 preclinical and 30 clinical articles were included. The methodological quality of studies was low, including mainly level IV studies. (4) Conclusions: This is the first report that provides a systematic description of the broad available preclinical and clinical literature on BCR-TKA. It underlines the current interest in improving kinematics and clinical outcome based on a more anatomical TKA design. The current review demonstrates the low methodological quality of clinical trials that have investigated BCR-TKA. Currently, there are insufficient data to support broad (“state of the art”) implantation of BCR-TKA. Preclinical and clinical research suggest, however, that the design has a potential benefit to achieve improved kinematics in the young and active arthroplasty patient and warrants future research for new-generation designs with optimal (tibial) fixation and reproducible (robot or navigated) surgical placement.

CONSORT Compliance in Randomized Clinical Trials of Regenerative Endodontic Treatments of Necrotic Immature Teeth: A Scoping Review

IntroductionThis study aimed to investigate methodological quality of clinical trials in regenerative endodontics and its compliance with the CONSORT statement. MethodsAn electronic search was performed in 8 electronic databases. Only clinical trials whose participants underwent regenerative endodontic treatment on necrotic permanent immature teeth were included. Quality assessment was performed using the Cochrane Collaboration’s Risk of Bias Tool (RoB, version 2.0). Compliance of articles with the CONSORT guidelines was assessed by a tool with scales: 0 = no description, 1 = deficient, and 2 = adequate description, totaling a maximum score of 32 points. The Mann-Whitney and Kruskal-Wallis tests were used to compare the scores among journals, studies, country, income levels, and publication periods. Spearman correlation analyses were performed between CONSORT compliance scores and 2019 journal CiteScore values, publication year, and quality assessment. ResultsTwenty studies were included. The average CONSORT compliance score was 20.95 (±6.19). The better reported items were the description of the interventions performed in the trials (100%), followed by the description of the number of patients analyzed, losses and exclusions (90%), and the hypothesis tested (85%). Within the 20 studies, 3 articles were classified as “low risk of bias,” 8 studies were classified as “some concerns,” and 9 studies were considered “high risk of bias.” Studies carried out in countries with higher income levels presented higher CONSORT scores. Significant moderate correlations were found between the CONSORT score and the percentage of risk of bias in low-risk domains (rs = 0.63; 95% CI, 0.31–0.94; P = .003) and the overall risk of bias categories (rs = 0.76; 95% CI, 0.54–0.98; P = .001). ConclusionsThe adequacy of reporting based on the CONSORT checklist items of regenerative endodontic trials was low with a moderate to high risk of bias.

Outcome measures to assess the effectiveness of endodontic treatment for pulpitis and apical periodontitis for use in the development of European Society of Endodontology (ESE) S3 level clinical practice guidelines: a protocol.

The European Society of Endodontology (ESE) is in the process of developing S3Level Clinical Practice Guidelines for the treatment of pulpal and apical disease for the benefit of clinicians and patients. In order to ensure a homogenous review process in the development of the clinical practice guidelines, it is essential that the core outcomes for all endodontic treatments are standardized and recommendations are made regarding minimum follow-up time specific to each outcome measure. In the absence of a recognized core outcome set in Endodontics, the current project aimed to follow an established consensus process to define the most appropriate clinician and patient-reported outcomes. As part of the project, recommendations will also be agreed regarding an acceptable minimum follow-up period for studies by literature review and group discussion. The selected outcome measures and follow-up periods will be used in subsequent systematic analyses of the literature to investigate the effectiveness of endodontic treatment to alleviate pulpitis and apical periodontitis. In this paper, previous reviews, ESE Guidelines and Position Statements were searched in order to compile a list of potentially important outcome measures for the treatment of pulpitis (working group 1), the nonsurgical treatment of apical periodontitis (working group 2), the surgical treatment of apical periodontitis (working group 3) and the regenerative treatment of apical periodontitis (working group 4). Initially, the two S3 guideline leads selected two independent senior clinical academics with experience of evidence-based dentistry to lead each of the four working groups forming a 10-member steering group. The working group leads in turn selected 32 academics with experience of evidence-based dentistry to lead the individual systematic reviews contained within the respective working groups. These 42 individuals make up the Guideline Development Group (GDG). Prior to the selected systematic reviewers commencing writing and submitting the review protocol, the complete list of outcome variables identified in this document will be ranked by the 42 members of the GDG in their importance to the individual patient using a 9-point Likert scale. A summary of the survey scores will thereafter be shared with the members of the group and the final list of clinician and patient-reported outcome measures rated as critical for decision making (7-9 on Likert scale by majority of survey participants) to guide systematic reviews will be consented and confirmed during an online meeting of the steering group. In this online meeting, another aspect with regard to meaningfulness of clinical trial results to be addressed in systematic reviews will be consented: length of follow-up. In order to develop high quality guidelines, it is suggested that the follow-up period after treatment should be related to the specific outcome measure being addressed; however, a minimum of one year for assessing the effectiveness of treatments for pulpitis and apical periodontitis should be considered. It is accepted, that selected research questions that focus on pain, swelling, medication taken or investigating diagnostic accuracy are likely to have shorter follow-up periods. As a result of the GDG consensus process, the outcome measures and length of follow-up will, alongside the use of standard instruments to assess the methodological quality of clinical trials and other comparative studies, be applied to all the commissioned systematic reviews that will inform the subsequent process when developing the ESE S3 Level Clinical Practice Guidelines.

Quality of clinical trials for the prevention of keratinocyte cancer.

Keratinocyte cancer (KC) is the most common form of cancer in humans. To our knowledge, no previous publications assessing the methodological quality of clinical trials for the prevention of KC have been recently published. We aim to assess the methodological quality of clinical trials focused on the prevention of KC in high-risk groups not receiving immunosuppressive therapy (NRIT) and propose solutions to improve the design of future trials. We searched clinical trials in which the main outcome was the prevention of KC in high-risk NRIT groups using the strategy published in the International Prospective Register of Systematic Reviews (PROSPERO registry), CRD42016045981. Consolidated Standards of Reporting Trials (CONSORT)criteria and the Cochrane Collaboration risk of bias tool were used to assess methodological quality. We analyzed 23 clinical trials. We found a high risk of attrition and reporting bias in 86.9% and 60.9% of the trials, respectively. Regarding the CONSORT criteria, in at least 40% of the trials, the authors omitted the following information: a description of the trial design, the number of losses and exclusions after randomization, the results of subgroup and adjusted analysis, the estimated effect size and the precision of primary and secondary outcomes. Methodological quality was improved in the recently published clinical trials compared to those published before the CONSORT criteria development. All clinical trials should report in detail the information used to assess potential risks of bias.

Construct validity of the Physiotherapy Evidence Database (PEDro) quality scale for randomized trials: Item response theory and factor analyses.

BackgroundThere is an agreement that the methodological quality of randomized trials should be assessed in systematic reviews, but there is a debate on how this should be done. We conducted a construct validation study of the Physiotherapy Evidence Database (PEDro) scale, which is widely used to assess the quality of trials in physical therapy and rehabilitation.MethodsWe analyzed 345 trials that were included in Cochrane reviews and for which a PEDro summary score was available. We used one‐ and two‐parameter logistic item response theory (IRT) models to study the psychometric properties of the PEDro scale and assessed the items' difficulty and discrimination parameters. We ran goodness of fit post estimations and examined the IRT unidimensionality assumption with a multidimensional IRT (MIRT) model.ResultsOut of a maximum of 10, the mean PEDro summary score was 5.46 (SD = 1.51). The allocation concealment and intention‐to‐treat scale items contributed most of the information on the underlying construct (with discriminations of 1.79 and 2.05, respectively) at similar difficulties (0.63 and 0.65, respectively). The other items provided little additional information and did not distinguish trials of different quality. There was substantial evidence of departure from the unidimensionality assumption, suggesting that the PEDro items relate to more than one latent trait.ConclusionsOur findings question the construct validity of the PEDro scale to assess the methodological quality of clinical trials. PEDro summary scores should not be used; rather, the physiotherapy community should consider working with the individual items of the scale.

Methodological Errors in Clinical Studies Published by Medical Journals of Ex-Yugoslav Countries.

Introduction:Certain methodological principles should be inexcusably followed when designing clinical or observational research to avoid bias and presentation of results that do not reflect the truth about the phenomenon that is the object of the study.Aim:The aim of this study was to compare the methodological quality of clinical trials and observational studies published in medical journals from ex-Yugoslav countries indexed in Pubmed/MEDLINE.Methods:Clinical studies published in medical journals of ex-Yugoslav countries were retrieved from the Pubmed/MEDLINE database, and the sample for analysis was randomly chosen from the retrieved publications. The rate of the most common errors in the design of clinical/observational studies was established by a careful reading of the sampled publications and their checking against predefined criteria.Results:The studies published in two countries that are now member states of the European Union (Slovenia and Croatia) have significantly higher citation rates, impact factor, and methodological quality scores than studies from other ex-Yugoslav countries. While publications from Croatia show clear improvement trend throughout the last two decades, which is visible also in the last 10 years in Slovenia and Bosnia and Herzegovina, quality of clinical research published in journals from Serbia was stagnating in the same period.Conclusions:There are significant differences in methodological quality and scientometric characteristics of clinical research published in medical journals of ex-Yugoslav countries that could be mitigated by more intensive training of clinical researchers in statistics and research design, as well as by more rigorous editorial practices.

Reporting and methodological quality of clinical trials on exercise therapy for Parkinson's disease

BackgroundExercise therapy is becoming extremely relevant as a new efficacious intervention in multiple medical fields. Although several clinical trials have reported benefits of exercise therapy for Parkinson's disease (PD), recommendations and prescriptions for its use in clinical practice remain limited. ObjectivesTo evaluate the methodological quality and publication rate of clinical trials on exercise therapy for PD. MethodsWe analyzed all clinical trials assessing exercise therapy for PD registered in the WHO International Clinical Trials Registry Platform and the ClinicalTrials.gov registries, from 2000 to 2017. We evaluated the methodological quality of trials using the Cochrane Risk of Bias criteria. ResultsA total of 236 clinical trials were identified. Only 70 (29.7%) trials reported their findings, and 61 (25.8%) had results published in scientific journals. Most trials had an unclear risk of bias concerning incomplete and selective outcome reporting and lacked data on the randomization process, allocation concealment, blinding of participants and personnel, and outcomes assessors. Aerobic capacity was the most frequent type of exercise intervention. ConclusionsAlthough a large number of trials on exercise are registered in international portals, the quality of reporting remains suboptimal and only a quarter of trials have their results published in scientific journals. These two factors, in addition to the heterogeneity of the interventions tested and the unsatisfactory reported methodological quality of most trials, compromise the interpretation of study results. Therefore, higher quality clinical trials reports are needed to establish exercise as part of the PD armamentarium.

A systematic review of the clinical effectiveness of monitoring patients with diabetes mellitus using individual blood glucose meters with function of transmitting measurements via gsm channel or via the internet

BACKGROUND: In recent years, there has been an active introduction of telecommunication technologies in various spheres of scientific and practical knowledge, including medicine. Diabetes mellitus (DM) is one of the most common chronic non-communicable diseases requiring constant monitoring of the patients condition. For telemedicine monitoring of patients with DM, glucose self-monitoring devices with the option of transmitting patients measurements via GSM channel or via the Internet have been developed.&#x0D; AIM: To evaluate the clinical effectiveness of telemedicine observation of patients with DM using individual glucose self-monitoring devices with option of transmitting patients measurements via a GSM channel or via the Internet.&#x0D; MATERIALS AND METHODS: Publications about clinical trials were searched in PubMed. The search, selection and evaluation of the methodological quality of clinical trials were carried out by two independent researchers. Clinical trials were included in the review if the clinical efficacy of remote monitoring of patients with DM using individual glucose self-monitoring devices with the option of transmitting the results of measurements taken by the patient via a GSM channel or via the Internet was evaluated in comparison with traditional observation methods.&#x0D; RESULTS: As a result of the systematic search, 10 original randomized controlled trials (RCTs) with different methodological quality were selected. It was found that the use of remote technologies for 12 months does not affect the level of glycated hemoglobin, however, it allows to increase the frequency of achieving individual therapeutic goals in patients with type 2 DM. In addition, it was found that the use of remote technologies allows to reduce the frequency of outpatient visits of patients with type 2 DM, but does not reduce the length of hospitalization and the frequency of an emergency calls of these patients.&#x0D; CONCLUSION: Thus, evidence was obtained of the potential therapeutic benefits of remote observation of patients with diabetes based on data from foreign clinical studies. Based on the results obtained, a Russian clinical trial of this medical technology can be recommended.

Clinical intervention studies of orofacial motricity: an analysis of the methodological quality of brazilian studies

ABSTRACT Purpose: to evaluate the methodological quality of clinical trials published in Brazilian journals. Methods: four trained independent researchers conducted a systematic literature search of all Brazilian speech therapy-related journals over the last ten years, whether the journals were active or inactive. All journal volumes published during that period were selected, and each researcher conducted an individual analysis to identify articles that focused primarily on orofacial motricity. The tools used were the Downs and Black Quality Checklist and the Jadad scale. Results: after the studies were selected and categorized, the final sample comprised six articles, all of which were classified as clinical trials. The observed methodological limitations included a lack of sample planning, randomization and blinding. Mean scores of 16.3 points on the Downs and Black Quality Checklist and 2.3 on the Jadad scale were obtained. Conclusion: the randomized controlled trials in the area of orofacial motricity are scarce in Brazilian literature, suggesting that studies in this area adopting this research design should be expanded and their quality should be improved to promote clinical practice based on scientific evidence.

A systematic review on the cardiovascular pharmacology of Emblica officinalis Gaertn.

Introduction: The Emblica officinalis (EO) fruit has traditionally been considered as a cardioactive medication and has demonstrated remarkable cardiovascular effects in the pharmacological literature. The present study systematically reviews EO’s potential for prevention and therapy of cardiovascular diseases (CVD). Methods: PubMed, ScienceDirect, Scopus, Proquest, Ebsco, Google, Google Scholar, Ovid, and Cochrane databases were searched from 1966 to 2017 for the English and non-English literature using the terms including the cognates of EO including amla, Emblic myrobalan, Emblica officinalis, Emblica pectinata , Indian gooseberry, and Phyllanthus emblica together with antioxidant, arrhythmia, cardioprotective, cardiotoxicity, heart disease, heart failure, hyperlipidemia, hypertension, myocardial dysfunction, and oxidative stress. The inclusion criteria were in vitro, animal, and clinical cardiovascular pharmacological studies conducted on EO and full-text accessibility. The exclusion criterion was studies in which a combination of EO and at least one other plant was investigated. The reference lists of the retrieved articles were also searched manually for additional eligible articles. The methodological quality of clinical trials was assessed by the Jadad scale, and animal studies were evaluated by the ARRIVE checklist. Results: Nineteen articles concerning the cardiovascular pharmacological effects of EO were included in this review. The plant has shown antiatherogenic, anticoagulant, hypolipidemic, antihypertensive, antioxidant, antiplatelet, and vasodilatory effects as well as lipid deposition inhibitory properties. Moreover, it prevents from doxorubicin and isoproterenol cardiotoxicity and myocardial ischemia/reperfusion injury, and improves vascular endothelial function in animal studies. Some high-quality clinical studies report the vasodilatory and myocardial antioxidant properties as well as anti-platelet aggregation effects of this plant. Conclusion: EO influences various cardiovascular risk-factors. However, there is not sufficient evidence to confirm the plant efficacy in preventing and treating CVD.

Protocolos para desmame da ventilação mecânica não invasiva: uma revisão sistemática

RESUMO O objetivo deste trabalho foi realizar revisão sistemática de estudos que investigaram protocolos de desmame da ventilação não invasiva (VNI) em indivíduos adultos ou idosos hospitalizados. Por meio dessa revisão, baseada no protocolo Prisma, foram selecionados estudos de oito bases de dados publicados em português, inglês ou espanhol. Os desfechos primários desta revisão foram taxa de sucesso de desmame da VNI, duração da VNI e duração da permanência na unidade de terapia intensiva (UTI) e no hospital, e como desfecho secundário foram considerados os efeitos adversos associados aos protocolos de desmame da VNI. A qualidade metodológica dos ensaios clínicos foi avaliada por meio da escala PEDro, e a escala de Downs e Black foi utilizada para a avaliação dos estudos observacionais. Das 18.476 referências iniciais, quatro atenderam aos critérios de inclusão e foram incluídas nesta revisão. Dois dos quatro artigos eram ensaios clínicos randomizados e os outros dois eram estudos observacionais. Os estudos envolveram pacientes idosos com insuficiência respiratória, principalmente por exacerbação da doença pulmonar obstrutiva crônica (DPOC) e edema agudo de pulmão cardiogênico. Foram observadas elevadas taxas de sucesso de desmame em três dos quatro estudos, e um destes demonstrou a superioridade da implementação de um protocolo de desmame imediato na redução da duração da VNI e da permanência na UTI. No entanto, devido à heterogeneidade e à baixa qualidade metodológica dos estudos, não foi possível fazer recomendação sobre a implementação dos protocolos de desmame nessa população.

A systematic review of anticancer effects of radix astragali.

To review the anticancer effects of Radix astragali (RA), one of the most commonly used herbs to manage cancer in East Asia, and its constituents and to provide evidence of clinical usage through previously performed clinical studies. Preclinical and clinical studies related to the anticancer effects of RA were searched from inception to November 2013 in electronic databases. Two reviewers independently investigated 92 eligible studies, extracted all the data of studies and appraised methodological quality of clinical trials. The studies were categorized into in vitro and in vivo experimental studies and clinical studies, and analyzed by saponins, polysaccharides, and flavonoids of RA constituents, RA fraction, and whole extract. In preclinical studies, RA was reported to have tumor growth inhibitory effects, immunomodulatory effects, and attenuating adverse effects by cytotoxic agents as well as chemopreventive effects. Saponins seemed to be the main constituents, which directly contributed to suppression of tumor growth through the activation of both intrinsic and extrinsic apoptotic pathway, modulation of intracellular signaling pathway, and inhibition of invasion and angiogenesis. Flavonoids suppressed tumor growth through the similar mechanisms with saponins. Polysaccharides showed immunomodulatory effects, contributing tumor shrinkages in animal models, despite the low cytotoxicity to cancer cells. Most of the clinical studies were performed with low evidence level of study designs because of various limitations. RA whole extracts and polysaccharides of RA were reported to improve the quality of life and ameliorate myelosuppression and other adverse events induced by cytotoxic therapies. The polysaccharides, saponins, and flavonoids of RA, and the whole extract of RA have been widely reported with their anticancer effects in preclinical studies and showed a potential application as a adjunctive cancer therapeutics with the activities of immunomodulation, anti-proliferation and attenuation of adverse effects induced by cytotoxic therapy.

Hexaminolevulinate hydrochloride in the detection of nonmuscle invasive cancer of the bladder.

Clinical trials have shown that hexaminolevulinate (HAL) fluorescence cystoscopy improves the detection of bladder tumors compared with standard white-light cystoscopy, resulting in more efficacious treatment. However, some recent meta-analyses report controversially on recurrence-free rates with this procedure. A systematic review of literature was performed from December 2014 to January 2015 using the PubMed, Embase and Cochrane databases for controlled trials on photodynamic diagnosis (PDD) with HAL. A total of 154 publications were found up to January 2015. Three of the authors separately reviewed the records to evaluate eligibility and methodological quality of clinical trials. A total of 16 publications were considered eligible for analysis. HAL-PDD-guided cystoscopy increased overall tumor detection rate (proportion difference 19%, 95% confidence interval [CI] 0.152-0.236) although the benefit was particularly significant in patients with carcinoma in situ (CIS) lesion (proportion difference 15.7%, 95% CI 0.069-0.245) and was reduced in papillary lesions (Ta proportion difference 5.9%, 95% CI 0.014-0.103 and T1 proportion difference 1.2%, 95% CI 0.033-0.057). Moreover, there were 15% of patients (95% CI 0.098-0.211) with at least one additional tumor seen with PDD. With regard to recurrence rates, the data sample was insufficient for a statistical analysis, although the evaluation of raw data showed a trend in favor of HAL-PDD. This meta-analysis confirms the increased tumor detection rate by HAL-PDD with a most pronounced benefit for CIS lesion.

PEDro or Cochrane to Assess the Quality of Clinical Trials? A Meta-Epidemiological Study.

ObjectiveThere is debate on how the methodological quality of clinical trials should be assessed. We compared trials of physical therapy (PT) judged to be of adequate quality based on summary scores from the Physiotherapy Evidence Database (PEDro) scale with trials judged to be of adequate quality by Cochrane Risk of Bias criteria.DesignMeta-epidemiological study within Cochrane Database of Systematic Reviews.MethodsMeta-analyses of PT trials were identified in the Cochrane Database of Systematic Reviews. For each trial PeDro and Cochrane assessments were extracted from the PeDro and Cochrane databases. Adequate quality was defined as adequate generation of random sequence, concealment of allocation, and blinding of outcome assessors (Cochrane criteria) or as trials with a PEDro summary score ≥5 or ≥6 points. We combined trials of adequate quality using random-effects meta-analysis.ResultsForty-one Cochrane reviews and 353 PT trials were included. All meta-analyses included trials with PEDro scores ≥5, 37 (90.2%) included trials with PEDro scores ≥6 and only 22 (53.7%) meta-analyses included trials of adequate quality according to the Cochrane criteria. Agreement between PeDro and Cochrane was poor for PeDro scores of ≥5 points (kappa = 0.12; 95% CI 0.07 to 0.16) and slight for ≥6 points (kappa 0.24; 95% CI 0.16-0.32). When combining effect sizes of trials deemed to be of adequate quality according to PEDro or Cochrane criteria, we found that a substantial difference in the combined effect size (≥0.15) was evident in 9 (22%) out of the 41 meta-analyses for PEDro cutoff ≥5 and 10 (24%) for cutoff ≥6.ConclusionsThe PeDro and Cochrane approaches lead to different sets of trials of adequate quality, and different combined treatment estimates from meta-analyses of these trials. A consistent approach to assessing RoB in trials of physical therapy should be adopted.

Methodological quality of clinical trials in pediatric dentistry research published in ISI journals, 2008-2012.

There are many studies about the methodological quality of articles in pediatric dentistry. However, there is no up-to-date information or the use of measurement guidelines designed and validated for this purpose. The aim of this article is to determine the methodological quantity and quality of clinical trials (CT) in pediatric dentistry published in four Web of Knowledge (ISI-indexed journals) between 2008 and 2012. Clinical trials published in four ISI pediatric dentistry journals were evaluated. Name of the journal, year of publication, country of the corresponding author, type of CT and main subject were registered. A scale of methodological quality (MINCIR) from 11 to 36 points was applied to evaluate each article, establishing 18 points as the cutoff for “good methodological quality”. The quality was calculated by country, subject area and journal. Of 1,151 published articles, 149 (12.5%) clinical trials were selected. Their methodological quality was 15.7±2.7 points. 17% of the CT achieved a score equal to or greater than a methodological quality considered “acceptable”. One in every 6 published clinical trials was of good methodological quality. This would actually make it difficult to adopt the results of these investigations into routine clinical practice or to include them in future systematic reviews and meta-analyses.

Meta-Analysis and Quality Assessment of Randomized Controlled Trials

Meta-analysis is the statistical combination of results from two or more separate studies. Potential advantages of meta-analyses include an increase in power, an improvement in precision, the ability to answer questions not posed by individual studies, and the opportunity to settle controversies arising from conflicting claims. However, they also have the potential to mislead seriously, particularly if specific study designs, within-study biases, variation across studies, and reporting biases are not carefully considered. It is important to be familiar with the type of data (e.g. dichotomous, continuous) that result from measurement of an outcome in an individual study, and to choose suitable effect measures for comparing intervention groups. Most meta-analysis methods are variations on a weighted average of the effect estimates from the different studies. Variation across studies (heterogeneity) must be considered. Random-effects meta-analyses allow for heterogeneity by assuming that underlying effects follow a normal distribution. Various judgments are required in the process of preparing a meta-analysis. Especially, quality assessment of randomized controlled trial is essential. There are several methods to assess the methodological quality of clinical trials, including scales, individual markers, and checklists. Analyzing the quality of studies makes the results of meta-analysis more reliable. Sensitivity analyses should be used to examine whether overall findings are robust to potentially influential decisions.

Weight loss in children and adolescents.

15% of children and adolescents in Germany are overweight, including 6.3% who are affected by obesity. The efficacy of conservative weight-loss treatments has been demonstrated, but there has not yet been a detailed analysis of their efficacy in terms of the amount of weight loss that can be expected. We re-evaluated the available evidence on this question, with particular attention to the methodological quality of clinical trials, in order to derive information that might be a useful guide for treatment. We conducted a systematic literature search of Medline for the period May 2008 (final inclusion date for a 2009 Cochrane Review) to December 2013. The identified studies were analyzed qualitatively. 48 randomized controlled clinical trials with a total of 5025 participants met the predefined inclusion criteria for this analysis. In the ones that met predefined criteria for methodological quality, conservative weight-loss treatments led to weight loss in amounts ranging from 0.05 to 0.42 BMI z score (standard deviation score of the body mass index) over a period of 12-24 months. Information on trial dropout rates was available for 41 of the 48 trials; the dropout rate was 10% or higher in 27 of these (66% ), and 25% or higher in 9 (22% ). The available evidence consistently shows that only a modest degree of weight loss can be expected from conservative treatment. Families seeking treatment should be informed of this fact. Future research should focus on determining predictive factors for therapeutic benefit, and on the evaluation of additional types of psychological intervention to promote coping with obesity.

Comment on Li et al.: Non-continuous versus continuous wound drainage after total knee arthroplasty: a meta-analysis

To the Editor: In this meta-analysis, Li et al. [1] assess the efficacy and safety of non-continuous and continuous wound drainage after total knee arthroplasty. They reached an important conclusion that noncontinuous drainage can achieve less haemoglobin loss (especially the four to six hour drain clamping) and postoperative visible blood loss with no increased risk of postoperative complications compared with continuous drainage. It is a valuable study. Nevertheless, there are some comments we would like to raise related to this article. Due to the absence of standard deviations in the study of Eum et al. [2], a previously published systematic review [3] estimated the standard deviations based on the range of data value, assuming the data as normally distributed data, which will inevitably generate bias. In this meta-analysis, the authors included the study by Eum et al. once again. Because of the absence of standard deviations, we suggest that the study by Eum et al. should be excluded from the meta-analysis by Li et al. Bian YY and Zhuang QY independently used the Cochrane Collaboration recommendations [4] to assess methodological quality of clinical trials. However, there were no detailed scores for each included trial. It is not appropriate that summary mean difference (MD) estimate with corresponding 95 % CIs were derived by using the method of inverse variance (IV) with the assumptions of a random-effects model (Fig. 6 in [1]). However, studies should be combined by using the DerSimonian and Laird random-effects model. The results of the meta-analysis further suggested that the heterogeneity (I2) between studies in Fig. 6 was found to be 88 %. This showed significantly higher variations between studies and cannot be comparable, which could potentially bias the results of this study. Moreover, I2 values above 90 % are very rare in any meta-analysis. We are eager to know the authors’ opinion about this. It is not sufficient that publication bias was only assessed by visual examination of funnel plot. Funnel plot symmetry should be further assessed by statistical tests (e.g., Egger’s linear regression test or Begg’s rank correlation test). Moreover, in the meta-analysis, publication bias was only assessed for haemoglobin loss. Actually, publication bias should be assessed for other comparisons (such as postoperative visible blood loss, range of motion, incidence of blood transfusion and postoperative complications). Therefore, publication bias may be present, distorting the meta-analysis. We agree on the following conclusions of the authors: noncontinuous drainage can achieve less haemoglobin loss (especially the four to six hour drain clamping) and postoperative visible blood loss with no increased risk of postoperative complications compared with continuous drainage, and more carefully and scientifically designed RCTs with large samples and long-term follow-up are required to further prove the claim.