Pilot Roll Out of the Xpert MTB/Rif for the Diagnosis of Pulmonary Tuberculosis in Two Municipalities in Brazil: a Stepped Wedge Trial
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 发起方
- 入组人数
- 34,758
- 试验地点
- 2
- 主要终点
- Notification Rate Ratio
研究概览
简要总结
Diagnosis of tuberculosis (TB) is a challenge because sputum smear, the most rapid and inexpensive test, often fails to detect the disease, in around 20 to 30% of cases. Culture of sputum yields a correct diagnosis in up to 90% of cases, but results are only available in 4 to 8 weeks, depending on the method. A new test (Xpert MTB/Rif) based on a rapid technique, named polymerase chain reaction (PCR), detects TB in less than 2 hours over 95% of cases, in addition to identification of cases resistant to certain drugs used to treat TB. The test is expensive, but several studies have demonstrated its accuracy, and since most steps are automatized, savings can be expected from human resources work. The aims of our study are (1) to evaluate this tool as a substitute test for sputum smears in routine conditions; (2) evaluate if it is cost-effective, meaning that effectiveness of the test may outweigh the extra cost, and (3) evaluate the acceptability of the test among patients and health care workers.
详细描述
The main study consisted of a group-randomized pragmatic trial following a stepped-wedge design. The GeneXpert machines will be installed in laboratories of the basic health units in Rio de Janeiro and Manaus, two cities with a high burden of the disease in Brazil. Doctors will prescribe routine tests in the clinics. When sputum specimens arrive in the laboratory, instead of performing smears, the Xpert MTB/Rif will be performed during the intervention period. If positive, a sputum smear will also be performed. The intervention period will be preceded by an observation period during which routine will be kept unchanged, i.e., only smears will be performed. The observation period will serve as a comparator (control). The investigators will then see how many more cases were detected during the intervention period, and in particular, how many smear-negative cases were detected, compared to the observation period.
A total of 35,000 specimens are expected to be tested with the new technology in 14 laboratories. Laboratories, not individuals, will be randomized.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Diagnostic
- 盲法
- None
入排标准
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •laboratories -and not subjects - will be randomized. All laboratories will start doing smears, when indicated by randomization, they will switch to Xpert MTB/Rif. There are no inclusion or
排除标准
- •for the labs. Sputum specimens from non-diagnostic (follow up) patients, second samples for diagnostic tests, insufficient volume/visible blood specimens will be excluded from the Xpert testing.
结局指标
主要结局
Notification Rate Ratio
时间窗: October 2012 (up to 2 years)
Proportion of additional bacteriologically confirmed notified TB cases during intervention period compared to the observation period Patients notified who had a positive test result. The notification rate (NR, i.e., number of notifications/100,000 population/year) ratio (NRR) is defined as the NR in the intervention period/NR in the observation period, and is presented in the statistical analysis section.
Costs Per Detected Case
时间窗: October 2012 (up to 2 years)
Costs per detected case were analyzed using a decision tree model from the national health system perspective. Incremental cost-effectiveness ratio (ICER) was calculated as (costs with Xpert - costs with smears)/(cases detected with Xpert - cases detected with smears). Negative ICERs mean cost saving.
次要结局
- NRR of Non-laboratory Tested TB (Cluster-averaged).(October 2012 (up to 2 years))
- NRR of Negative-laboratory TB (Cluster-averaged).(October 2012 (up to 2 years))