本文针对二分类变量结局指标相对（而非绝对）治疗效果的不一致性。证据本身不会因不同研究结果具有一致性而升级，但可能因不一致而降低质量级别。衡量一致性的标准包括点估计值的相似性、可信区间的重叠程度以及统计学判定标准包括异质性检验和I2。系统评价作者应提出并检验少数几个与患者、干预措施、结局指标以及方法学相关的先验假设以探寻异质性来源。当不一致性很大且无法解释时，因不一致性而降低质量级别是恰当的，特别当某些研究显示有显著益处而其他显示无益甚至有害时（而非仅是疗效大与疗效小的比较）。明显的亚组效应可能不可靠。如果亚组效应满足以下条件，其可信度将会增加：基于少数几个有具体方向的先验假设、亚组比较来自研究内而非研究间、交互检验的P值小、结果有生物学意义。
Objective To investigate an evaluation method of medical literature applicability to clinical work， and provide a convenient way for physicians to search for the best evidence. Methods Delphi method was used to choose appropriate evaluating indexes， analytic hierarchy process was performed to determine the weighing of each index， and the formula to calculate medical literature applicability was formed. The practicability of this formula was evaluated by consistency checking between the formula’s results and experts’ opinions on literature applicability. Results Five evaluating indexes were determined， including literature’s publishing year （X1）， whether the target questions were covered （X2）, sample size （X3）， trial category （X4）， and journal level （X5）. The formula to calculate medical literature applicability was Y=3.93 X1＋11.78 X2＋14.83 X3＋44.53 X4＋24.93 X5. The result of consistency checking showed that the formula’s results were highly consistent with experts’ opinions （Kappa=0.75， P＜0.001）. Conclusion The applicability formula is a valuable tool to evaluate medical literature applicability.
本文介绍证据质量分级的GRADE方法。GRADE将证据质量分为高、中、低和极低四个级别。该分级应用于证据群，而非针对个别研究。系统评价中，质量反映了我们认为效应估计值正确的把握度。对推荐意见而言，质量反映了我们认为效应估计值足以支持某特定推荐的把握度。随机对照试验初定为高质量证据，观察性研究初定为低质量证据。GRADE中所使用的质量一词不只是意味着偏倚风险，还可能受研究结果的不精确性、不一致性和间接性，及发表偏倚的影响。此外，若干因素可增加我们对效应估计值的把握度。GRADE提供了一种系统方法来思考并报告各因素。GRADE将评估证据质量的过程与给出推荐建议的过程分开。推荐强度的判断不仅依赖于证据质量。
目的 利用局部一致性（ReHo）方法探测创伤后应激障碍（PTSD）患者在静息状态下是否存在着大脑功能异常。 方法 2010年5月－7月对18例未经治疗的地震PTSD患者和19例同样经历地震但未患PTSD的对照者进行了静息态功能磁共振成像（Rs-fMRI） 扫描。应用ReHo方法处理Rs-fMRI数据，得出PTSD患者的异常脑区，并将患者存在组间差异的脑区ReHo值与临床用PTSD诊断量表（CAPS）、汉密尔顿抑郁量表（HAMD）和汉密尔顿焦虑量表（HAMA）分别进行相关分析。 结果 ① PTSD组ReHo显著增加的脑区包括右侧颞下回、楔前叶、顶下叶、中扣带回，左侧枕中回以及左/右侧后扣带回；ReHo显著降低的脑区包括左侧海马和左/右侧腹侧前扣带回。② 异常脑区中后扣带回和右侧中扣带回ReHo与HAMD呈负相关（中扣带回r=?0.575，P=0.012；右侧后扣带回：r=?0.507，P=0.032），其余脑区ReHo与临床指标无明显相关性（P＞0.05），左侧海马与CAPS的相关性相对其他脑区较大（r=?0.430，P=0.075）。 结论 PTSD患者在静息状态下即存在着局部脑功能活动的降低和增加，ReHo方法可能有助于研究PTSD患者静息状态脑活动。
This study sought to reveal the difference of brain functions at resting-state between subjects with sub-health and normal controls by using the functional magnetic resonance imaging (fMRI) technology. Resting-state fMRI scans were performed on 24 subjects of sub-health and on 24 healthy controls with gender, age and education matched with the sub-health persons. Compared to the healthy controls, the sub-health group showed significantly higher regional homogeneity (ReHo) in the left post-central gyrus and the right post-central gyrus. On the other hand, the sub-health group showed significantly lower ReHo in the left superior frontal gyrus, in the right anterior cingulated cortex and ventra anterior cingulate gyrus, in the left dorsolateral frontal gyrus, and in the right middle temporal gyrus. The Significant difference in ReHo suggests that thebsub-health persons have abnormalities in certain brain regions. It is proved that its specific action and meaning deserves further assessment.
For the questions of deeply researching abnormal neuromuscular coupling and better evaluating motor function of stroke patients with motor dysfunction, an effective intermuscular coherence analysis method and index are studied to explore the neuromuscular oscillation and the pathomechanism of motor dysfunction, based on which an assessment standard of muscle function is established. Firstly, the contrastive analysis about the intermuscular coherence of antagonistic muscle of affected and intact upper limbs of stroke patients was conducted. Secondly, a significant indicator of Fisher's Z-transformed coherence significant indicator was defined to quantitatively describe the coupling differences in certain functional frequency domain between surface electromyogram (sEMG) of affected and intact sides. Further more, the relationship between intermuscular coherence and motor task was studied. Through the analysis of intermuscular coherence during elbow flexion-extension of affected and intact sides, we found that the intermuscular coherence was associated with motor task and the stroke patients exhibited significantly lower beta-band intermuscular coherence in performing the task with their affected upper limbs. More conclusion can be drawn that beta-band intermuscular coherence has been found concerned with Fugle-Meyer scale, which indicates that beta-band intermuscular coherence could be an index assisting in evaluating motor function of patients.
Compared with traditional head to head meta-analysis, network meta-analysis has more confounding factors and difficulties to handle. Due to the mutual transitivity of evidence in network meta-analysis, heterogeneity may be brought into indirect meta-analysis. Hence, effective differentiation and correct handling of heterogeneity are being current focus. In order to ensure the reliability of the results of network meta-analysis, the concept of homogeneity is proposed and a series of methods are developed for differentiation and handling of homogeneity. Based on the extension of Bucher methods, current methods for differentiation and handling of homogeneity has extended to ten quantitative measures (eg., node analysis method, hypothesis tests, and two-step method). However, because of the differences and the focus of fundamental methodological theories as well as the limitation of statistics power, no highly-effective method has been worked out. Therefore, the exploration of highly-effective, simple and high-resolved methods are still needed.
ObjectiveTo introduce sensitivity and homogeneity tests in network meta-analysis and its implementation in R software. MethodsUsing an example, we performed sensitivity analysis by comparing the random effect model with the fixed effect model. Homogeneity analysis was performed using metaphor package and combinat package in R software. ResultsThe results of the two models were similar, and the data was steady. The results of homogeneity analysis showed that the confidential intervals in all loops were crossed over with blank value; and direct and indirect estimates of the effects in network meta-analysis were not significantly different, with good homogeneity. ConclusionNetwork meta-analysis is a kind of indirect comparison analysis method, and its sensitivity is especially important. The introduction of homogeneity makes network meta-analysis more accurate. Using R software for sensitivity and homogeneity analysis in network meta-analysis is a feasible method.