在GRADE方法中，若多数相关证据来自高偏倚风险的研究，则起初被定为高质量证据的随机试验和低质量证据的观察性研究均有可能被降低质量等级。随机试验已确定的局限性包括：未进行分配隐藏、未实施盲法、未报告失访情况及未恰当考虑意向性治疗原则。最近提出的局限性包括：因明显获益而早期终止试验和基于结果选择性报告结局。观察性研究的主要局限性包括使用不合适的对照及未能充分调整预后的不平衡。偏倚风险可因不同结果而异（如全死因死亡率的失访远少于生命质量的失访），许多系统评价都容易忽略这一点。在决定是否因偏倚风险而降低质量等级时，不管是随机试验还是观察性研究，作者不应采用对各个研究取平均值的方法。相反，对任何单个结果，当同时存在高、低偏倚风险的研究时，则应考虑只纳入较低偏倚风险的研究。
The original meaning of “allocation concealment” is that the statistician and the trial designer who generated the random sequence and allocation sequence should not recruit and allocate the participants for the purpose of avoiding selection bias. In the process of generating allocation sequence, combined blinding measures are so called “setting blinding”, for instance, by using “double simulation”. We use a example to describe how to perform an adequate allocation and conceal the sequence, and setting blinding. Another example is used to describe how to report the methods of randomization, allocation concealment and the effect of blinding, etc.
【摘要】 目的 探讨细菌性胶原酶对创口感染情况的影响。 方法 2006年11月-2006年12月，对28只新西兰兔分为实验组和对照组，分别予细菌性胶原酶溶液及生理盐水浸润创口并缝合。观察创口感染及局部皮肤的炎性细胞浸润情况。 结果 实验组与对照组创口感染率差别无统计学意（Pgt;0.05），炎性细胞差别无统计学意义（Pgt;0.05）。 结论 细菌性胶原酶在创伤修复过程中不能直接降低感染率，对炎性细胞的迁移并无明显的作用。 【Abstract】 Objective To assess the effects of bacterial collagenase on the wound infection. Methods A total of 28 New Zealand rabbits have chosen from November to December 2006, and were divided into a laboratorial group and a control group. We sutured the wounds and soaked them by the bacterial collagenase liquid or by the physiologic saline solution. The infection and the inflammatory cells of the skin around the wound were observed. Results The difference of the infection rates between the two groups was not statistically significant (P=0.62), nor the difference of inflammatory cells (P=0.84). Conclusions Bacterial collagenase can not decrease the rate of infection directly, and had no obvious effect on the transferring of inflammatory cells.
Blinding is an effective measure to control and reduce the bias caused by the subjective factors of participants in a study. However, the failure of blinding results in more bias. Therefore, it is necessary to assess blinding quality in clinical trials involving blinding. The relevant international articles and methods of blinding assessment were summarized in this study. According to the present situation of blinding assessment, researchers don't pay enough attention to the assessment of blinding quality, relevant studies lack, comprehensive methods and tools for blinding quality, and researchers have discrepancy with time points in blinding quality. Therefore, it is necessary to conduct further studies in all aspects, and it is suggested that comprehensive blinding quality scales should be developed according to the key influencing factors of the implementation of blinding. Through the assessment of the implementation of key factors, the risk and degree of blinding should be confirmed in order to better interpret and assess researcher results.
ObjectiveTo observe the accuracy of location and operation of traditional blind acupotomy lysis in the treatment of scapulohumeral periarthritis by using the high-frequency ultrasound.MethodsForty-two patients with scapulohumeral periarthritis diagnosed in the First Affiliated Hospital of Xinjiang Medical University and Urumqi Hospital of Traditional Chinese Medicine from February to April 2018 were selected. Four common sites of needle knife in the treatment of scapulohumeral periarthritis were operated blindly, and the process of the needle insertion points location and needle perform were both observed by high-frequency ultrasound.ResultsUsing high-frequency ultrasound to observe and confirm the bare-handed positioning point and needle-knife operating point, we found that the accuracy rate of bare-handed positioning needle-point was 100.0% (42/42). In the process of needling, the accuracies of needle insertion at the point of small tubercle of humerus and the point of bursa of deltoid muscle were high, which was 95.2% (40/42) and 100.0% (42/42), respectively. However, because of the deviation of the needle depth and direction, the accuracies of needle insertion at the coracoid point and the sulcus point between the humeral tubercles were low, which was 45.2% (19/42) and 4.8% (2/42), respectively.ConclusionsTraditional acupotomy lysis is a commonly used method of needle knife treatment. Using high-frequency ultrasound, it is found that even by experienced needle knife doctors, there may still be positioning deviation when using blind method to insert needles. Because the visualization of clinical needle knife is difficult to be carried out universally due to the limitations of time and technology, it is suggested that high-frequency ultrasound could be used as a visualization teaching tool in the training of needle knife operation to assist the training of blind needle knife operation technology, which may improve the accuracy of blind needle knife operation.