Chang Eva, Luelmo Fabio, Baydulloeva Zamira, Joncevska Marija, Kasymova Guljamol, Bobokhojaev Oktam, Mohr Tom
Harvard Medical School, Boston, MA, USA.
TB Control Programmes, Geneva, Switzerland.
Cent Asian J Glob Health. 2016 Mar 4;4(2):230. doi: 10.5195/cajgh.2015.230. eCollection 2015.
Tajikistan has a laboratory network with three levels of tuberculosis (TB) laboratories. The external quality assessment (EQA) of sputum smear microscopy was implemented in 2007. The objective of this study was to evaluate the EQA system and identify potential performance improvement strategies in TB microscopic laboratories in Sughd, Tajikistan.
This is a cross-sectional study based on retrospective record review and secondary data analyses on Acid-Fast Bacilli (AFB) microscopy data and EQA reading results collected between the first quarter of 2011 and the fourth quarter of 2013. Descriptive analyses were conducted to examine the overview of microscopy laboratories activities, EQA results, and laboratory performance.
Of the 123,874 smears examined between 2011 and 2013, 11,522 (9.30%) were re-checked by the EQA system. The population TB screening rate rose from 0.46% in 2011 to 0.57% in 2013, and the case positivity rate decreased from 6.98% to 4.80%. The regional EQA results showed a reduction in high false-positive, high false-negative, and low false-negative errors. False-positive errors had decreased from 0.13% in 2011 to 0.07% in 2013, and false-negative errors from 0.91% in 2011 to 0.15% in 2013. Regional sensitivity of smear microscopy, when compared to re-checking controller, increased from 88.2% in 2011 to 97.2% in 2013. The regional specificity level remained relatively stable at above 99%.
Our study found that a decreasing trend of case positivity rate from 2011 to 2013 in Sughd, though the overall laboratory workload was on the rise. In addition, EQA results showed an overall error reduction and an improved sensitivity of smear microscopy in the region. The overview of microscopic laboratory activities and the actual evaluation of the EQA system on sputum smear microscopy complement each other in providing a better picture on the progress of TB laboratory strengthening. We recommend similar approaches to be adapted by future evaluations on TB microscopic laboratories, particularly among countries of high burden. Interactive training and feedback loops are crucial to improving TB surveillance in Tajikistan.
塔吉克斯坦拥有一个由三级结核病实验室组成的实验室网络。痰涂片显微镜检查的外部质量评估于2007年实施。本研究的目的是评估苏格德州结核病显微镜实验室的外部质量评估系统，并确定潜在的性能改进策略。
这是一项横断面研究，基于对2011年第一季度至2013年第四季度收集的抗酸杆菌（AFB）显微镜检查数据和外部质量评估读数结果的回顾性记录审查和二次数据分析。进行描述性分析以检查显微镜实验室活动、外部质量评估结果和实验室性能的概况。
在2011年至2013年期间检查的123,874份涂片样本中，有11,522份（9.30%）由外部质量评估系统重新检查。结核病筛查率从2011年的0.46%上升到2013年的0.57%，病例阳性率从6.98%下降到4.80%。地区外部质量评估结果显示，高假阳性、高假阴性和低假阴性错误有所减少。假阳性错误从2011年的0.13%降至2013年的0.07%，假阴性错误从2011年的0.91%降至2013年的0.15%。与重新检查的对照相比，涂片显微镜检查的地区敏感性从2011年的88.2%提高到2013年的97.2%。地区特异性水平保持相对稳定，高于99%。
我们的研究发现，尽管实验室总体工作量在增加，但2011年至2013年期间苏格德州的病例阳性率呈下降趋势。此外，外部质量评估结果显示该地区总体误差减少，涂片显微镜检查灵敏度提高。显微镜实验室活动概况和痰涂片显微镜检查外部质量评估系统的实际评估相互补充，能更好地呈现结核病实验室强化工作的进展情况。我们建议未来对结核病显微镜实验室的评估采用类似方法，特别是在高负担国家。交互式培训和反馈循环对于改善塔吉克斯坦的结核病监测至关重要。
