Objective To compare the efficiency of epidermis cell culture between big graft method and small strip method. Methods The big graft method was to cut the skin tissue reticularly from dermis layer while the epidermis were not cut off. After it was digested fully in trypsin, theepidermis was separated from skin and was used to culture epidermal cells. The small strip method was routine. The time to cut the skin and to separate the epidermis was recorded, and the number and quality of cells were compared between two methods. Results It took 8-10 minutes to cut an area of 5 cm2 skin into small strips and 1-2 minutes into big grafts. It took 10-15 minutes to separate the epidermis from the same area skin by small strip method and 2 minutes by big graft method. The cells showed better vigor and its number was more by big grafts than by small strips.The chance of fibroblast contamination was reduced obviously. Conclusion The big graft method is simpler than the small strip method and can culture more epidermis cells with less chance of fibroblast contamination.
背景与目的 对卫生保健干预措施进行决策权衡需要有不良和有益的可靠证据,然而绝大多数系统评价针对的是研究方法非常成熟的随机对照试验及其有效性评价,系统地评价不良反应的方法尚未完善,对研究者而言,能作为相关指南的资源很少.为此,作者在文中报告了对不良反应进行系统评价的新近体会,同时提出进一步实践和研究的建议.方法 描述并比较3个包含不良反应评价的药物干预的系统评价的方法学,重点评价其研究问题、研究设计和质量评价.结果 1个研究关注于如何根据提供的特殊不良反应数据建立卫生经济学模式,而其它两个研究涉及更广泛的问题.尽管每个评价对纳入标准的定义不同,但它们均纳入了随机和观察性数据.对研究质量的评价采用了标准方法.由于研究设计不良、报告不充分和现有研究工具有限,在运用纳入标准和评估研究质量时,研究者遇到了各种问题.最终发现,3个评价都做了大量的工作,但对卫生保健决策者有用的资料不多.研究者确认,改善的关键在于如何提出系统评价的问题和发展不良反应研究的质量评价方法学.结论 若不良反应的系统评价只专注于一个中心问题,那么它会提供与临床决策更相关的资料,也有利于明确纳入系统评价研究的类型.系统评价中不良反应的质量评估的方法学需要进一步完善.
When prioritizing clinical questions in the development of the clinical practice guidelines, clinical questions with high recognition and low variability, or high score and less disagreement among experts were often prioritized, while questions with high recognition but high variability were excluded. By this approach, clinical questions with practical value but also showed high variability due to different causes were not accepted as priorities. There were some methodological and clinical limitations by doing so. By summarizing the causes and connotations of expert opinion variability in terms of clinical experience, expertise and values, this paper analyzed the advantages of the variability quantification application, and proposed corresponding methodological recommendations, so as to provide references for guideline developers in the priority selection of clinical questions.
Objective To investigate the methodological characteristics of observational studies on the correlation between drug exposure during pregnancy and birth defects. Methods The PubMed database was searched from January 1, 2020 to December 31, 2020 to identify observational studies investigating the correlation between drug use during pregnancy and birth defects. Literature screening and data extraction were conducted by two researchers and statistical analysis was performed using R 3.6.1 software. Results A total of 40 relevant articles were identified, of which 8 (20.0%) were published in the four major medical journals and their sub-journals, 21 (42.5%) were conducted in Europe and the United States, and 4 were conducted (10.0%) in China. Cohort studies (30, 75.0%) and case-control studies (10, 25%) were the most commonly used study designs. Sixteen studies (40.0%) did not specify how the databases were linked. Sixteen studies (40.0%) did not report a clear definition of exposure, while 17 studies (42.5%) defined exposure as prescribing a drug that could not be guaranteed to have been taken by the pregnant women, possibly resulting in misclassification bias. Six studies (15.0%) did not report the diagnostic criteria for birth defects and 18 studies (45.0%) did not report the types of birth defects. In addition, 33 studies (82.5%) did not control for confounding factors in the study design, while only 19 studies (47.5%) considered live birth bias. Conclusion Improvements are imperative in reporting and conducting observational studies on the correlation between drug use during pregnancy and birth defects. This includes the methods for linking data sources, definition of exposure and outcomes, and control of confounding factors. Methodological criteria are needed to improve the quality of these studies to provide higher quality evidence for policymakers and researchers.
Currently, there is a lack of clarity and standardization regarding the implementation details of interventions in traditional Chinese medicine clinical practice guidelines (CPGs). This in methodological guidance for standardizing the implementation prescription adversely impacts the quality of implementation and hinders the clinical application rate of recommendations. Through in-depth analysis of implementation prescription of evidence-based CPGs in traditional Chinese medicine, we identified the challenges associated with standardization. In response, we propose enhancing the technical specifications of implementation prescriptions, advocating for improved formulation processes, diverse reporting approaches, and standardizedological guidelines. These recommendations aim to serve as a methodological reference and guidance for clinical practice guideline developers.
ObjectiveTo analyze the reporting and methodological quality of tranexamic acid meta-analyses published in Chinese journals. MethodsThe CNKI, WanFang Data, and CBM databases were electronically searched for meta-analyses of tranexamic acid from inception to August 12th, 2021. Two reviewers independently screened literature, extracted data, and used AMSTAR 2 and PRISMA 2009 to assess the methodological and reporting quality of publications. ResultsA total of 68 meta-analyses were included. The identified meta-analyses required improvement for items 2, 3, 4, 7, 8, 10, 12, 15, and 16 in the AMSTAR 2, and items 2, 5, 8, 12, 15, 17, 22, 24, and 27 in the PRISMA 2009 assessments, respectively. The methodological and reporting quality scores were positively correlated (rs=0.36, P=0.002). Linear regression analysis identified the mentioning of PRISMA and funding support as the independent factors potentially affecting the reporting quality score (P<0.05). ConclusionsBoth the methodological and reporting quality of the tranexamic acid meta-analyses published in Chinese journals require improvement.
The pre-market approval and clinical application of innovative medical devices should be based on high-quality evidence, proving their reliability, safety and effectiveness. In 2016, the IDEAL (Idea, Development, Exploration, Assessment and Long-term follow-up) collaboration modified the original IDEAL framework and recommendation to the IDEAL-D methodological framework for the entire life cycle evaluation of innovative medical devices. The framework included five stages, namely the preclinical development stage, idea stage, exploration stage, assessment stage and long-term follow-up stage. This paper aims to interpret the study purpose, content and design at each step of the IDEAL-D framework based on IDEAL framework and recommendation (2019) to provide practical methodological guidance for the design and conduct of clinical research on innovative medical devices.
Objective To assess the methodological quality of systematic reviews/ meta-analysis of burden of illness, analyses the factors affecting it, so as to provide a reference basis for improving the methodological quality of related studies. Methods Systematic reviews/ meta-analysis of burden of illness were identified in PubMed, searching from its inception to 12 October 2024. Systematic reviews/ meta-analysis of burden of illness was included, the methodological quality of the included literature was evaluated using AMSTAR-2, and data were extracted using Excel 2021. Results A total of 308 systematic reviews/ meta-analysis were included, with a fluctuating upward trend in the number of publications from 2006 to 2024; of these, a total of 12 were rated as low quality. According to the AMSTAR-2 entries, the largest number of documents fully conformed to entry 16 (82.14%), followed by entry 5 (81.49%), and entry 8 (72.73%); one document conformed to entry 10 (0.32%), and relatively few conformed to entry 12 (68.83%), entry 13 (85.39%), and entry 15 (67.53%). ConclusionThe methodological quality of systematic reviews/ meta-analysis of burden of illness needs to be improved, and the main problems include the lack of pre-study protocols, the absence of a list of excluded literature, and the less than adequate explanation of heterogeneity and risk of bias, etc. There is still a need to further improve the methodological quality of the systematic reviews and to promote the long-term development of evidence based medicine.
Objective To understand the feasibility of application of objective performance criteria single arm trial in clinical efficacy evaluation of traditional Chinese medicine, and put forward theoretical countermeasures for the difficulties in application, so as to provide references for promoting the application of objective performance criteria single arm trial in clinical efficacy evaluation of traditional Chinese medicine in the future. Methods Semi-structured qualitative interviews were conducted among clinical experts and methodologists who were involved in objective performance criteria single arm trials using purposive sampling combined with snowball sampling and a preset interview outline. To explore the application situations, influencing factors and difficulties in the application process of objective performance criteria single arm trial in the clinical efficacy evaluation of traditional Chinese medicine, and put forward theoretical countermeasures. Results A total of 12 respondents were interviewed, including 7 clinical experts and 5 methodologists. The interview content was summarized and formed into 216 codes. After category analysis, 5 categories were formed, including the applicable situations, advantages, limitations, difficulties in the application process and theoretical countermeasures. The respondents believed that objective performance criteria single arm trial could be used as an alternative plan when controlled trials could not be carried out, or as a preliminary exploration or evidence supplement. It had the advantages of reducing sample size, good patient compliance, saving resource input, and relatively rigorous design. However, its application was limited due to low awareness and unclear level of evidence. The application difficulties included the setting of objective performance criteria, sample size calculation, quality control and statistical analysis. It was suggested to form a standard to promote its application in the efficacy evaluation of traditional Chinese medicine. Conclusion The design of objective performance criteria single arm trial is consistent with the characteristics of clinical research of traditional Chinese medicine. However, because there is no control group, the validity of objective performance criteria single arm trial is challenged, which hinders its further application in the clinical efficacy evaluation of traditional Chinese medicine. By standardizing the selection of objective performance criteria, calculation of sample size, statistical analysis methods and research implementation steps, the strength of its demonstration and the recognition can be improved to a certain extent, but attention should be paid to avoid its misuse. In the future, the objective performance criteria single arm trial may be used as a basis to further explore the new direction of scientific research methods for clinical efficacy evaluation of traditional Chinese medicine.
Indirect comparison refers to a comparison of different healthcare interventions using data from separate studies, and is often used because of a lack of, or insufficient evidence from head-to-head comparative trials. We aimed to summarize the definition, fundamental theory, type, relevant statistical contents, and to clarify some question on how to use indirect comparison, in order to attract more researchers' attention and promote methodological development of indirect comparison.