AIM: To quantitatively summarize and appraise the available evidence of urea breath test(UBT) use to diagnose Helicobacter pylori(H. pylori) infection in patients with dyspepsia and provide pooled diagnostic accuracy ...AIM: To quantitatively summarize and appraise the available evidence of urea breath test(UBT) use to diagnose Helicobacter pylori(H. pylori) infection in patients with dyspepsia and provide pooled diagnostic accuracy measures.METHODS: We searched MEDLINE, EMBASE, Cochrane library and other databases for studies addressing the value of UBT in the diagnosis of H. pylori infection. We included cross-sectional studies that evaluated the diagnostic accuracy of UBT in adult patients with dyspeptic symptoms. Risk of bias was assessed using QUADAS(Quality Assessment of Diagnostic Accuracy Studies)-2 tool. Diagnostic accuracy measures were pooled using the random-effects model. Subgroup analysis was conducted by UBT type(13C vs 14C) and by measurement technique(Infrared spectrometry vs Isotope Ratio Mass Spectrometry).RESULTS: Out of 1380 studies identified, only 23 met the eligibility criteria. Fourteen studies(61%) evaluated 13 C UBT and 9 studies(39%) evaluated 14 C UBT. There was significant variation in the type of reference standard tests used across studies.Pooled sensitivity was 0.96(95%CI: 0.95-0.97) andpooled specificity was 0.93(95%CI: 0.91-0.94). Likelihood ratio for a positive test was 12 and for a negative test was 0.05 with an area under thecurve of 0.985. Meta-analyses were associated with a significant statistical heterogeneity that remained unexplained after subgroup analysis. The included studies had a moderate risk of bias.CONCLUSION: UBT has high diagnostic accuracy for detecting H. pylori infection in patients with dyspepsia. The reliability of diagnostic meta-analytic estimates however is limited by significant heterogeneity.展开更多
GRADE建议通过检查95%可信区间(CI)为决定不精确性的最佳方法。在指南实际运用中,如果CI的上、下限值代表了真实效应,而临床实际情况与之不符时,必须降低证据质量级别(即对效应估计值的把握度)。除外当效应值很大且可信区间提示效应稳健...GRADE建议通过检查95%可信区间(CI)为决定不精确性的最佳方法。在指南实际运用中,如果CI的上、下限值代表了真实效应,而临床实际情况与之不符时,必须降低证据质量级别(即对效应估计值的把握度)。除外当效应值很大且可信区间提示效应稳健,而总样本量不大且事件数很少的情况,其他应考虑因不精确性而降低证据质量级别。作此决定时,可计算有足够检验效能的单个试验所需的病例数(定义为"最优信息样本量",即optimal information size,OIS)。对连续型变量,我们建议用类似方法,首先考虑可信区间上、下限值,再计算OIS。系统评价(SR)所需方法略有不同。如果95%CI不包括相对危险度(RR)为1,且总事件发生数或病例数超过OIS标准,则精确性良好。如果95%CI包括了明显获益或危害(我们建议以RR值<0.75或>1.25作粗标准),即使达到OIS要求,因不精确性而降低证据质量级别较恰当。展开更多
文摘AIM: To quantitatively summarize and appraise the available evidence of urea breath test(UBT) use to diagnose Helicobacter pylori(H. pylori) infection in patients with dyspepsia and provide pooled diagnostic accuracy measures.METHODS: We searched MEDLINE, EMBASE, Cochrane library and other databases for studies addressing the value of UBT in the diagnosis of H. pylori infection. We included cross-sectional studies that evaluated the diagnostic accuracy of UBT in adult patients with dyspeptic symptoms. Risk of bias was assessed using QUADAS(Quality Assessment of Diagnostic Accuracy Studies)-2 tool. Diagnostic accuracy measures were pooled using the random-effects model. Subgroup analysis was conducted by UBT type(13C vs 14C) and by measurement technique(Infrared spectrometry vs Isotope Ratio Mass Spectrometry).RESULTS: Out of 1380 studies identified, only 23 met the eligibility criteria. Fourteen studies(61%) evaluated 13 C UBT and 9 studies(39%) evaluated 14 C UBT. There was significant variation in the type of reference standard tests used across studies.Pooled sensitivity was 0.96(95%CI: 0.95-0.97) andpooled specificity was 0.93(95%CI: 0.91-0.94). Likelihood ratio for a positive test was 12 and for a negative test was 0.05 with an area under thecurve of 0.985. Meta-analyses were associated with a significant statistical heterogeneity that remained unexplained after subgroup analysis. The included studies had a moderate risk of bias.CONCLUSION: UBT has high diagnostic accuracy for detecting H. pylori infection in patients with dyspepsia. The reliability of diagnostic meta-analytic estimates however is limited by significant heterogeneity.
文摘GRADE建议通过检查95%可信区间(CI)为决定不精确性的最佳方法。在指南实际运用中,如果CI的上、下限值代表了真实效应,而临床实际情况与之不符时,必须降低证据质量级别(即对效应估计值的把握度)。除外当效应值很大且可信区间提示效应稳健,而总样本量不大且事件数很少的情况,其他应考虑因不精确性而降低证据质量级别。作此决定时,可计算有足够检验效能的单个试验所需的病例数(定义为"最优信息样本量",即optimal information size,OIS)。对连续型变量,我们建议用类似方法,首先考虑可信区间上、下限值,再计算OIS。系统评价(SR)所需方法略有不同。如果95%CI不包括相对危险度(RR)为1,且总事件发生数或病例数超过OIS标准,则精确性良好。如果95%CI包括了明显获益或危害(我们建议以RR值<0.75或>1.25作粗标准),即使达到OIS要求,因不精确性而降低证据质量级别较恰当。
