Bill & Melinda Gates Foundation.

Bill and Melinda Gates Foundation.

No abstract

BackgroundAccurate surveillance data are paramount to effective TB control. The Republic of South Africa’s National TB Control Program (NTP) has conducted TB surveillance since 1995 and adopted the Electronic TB Register (ETR) in 2005. This evaluation aimed to determine the completeness and reliability of data in the Republic of South Africa’s TB Surveillance System.MethodsThree of nine provinces, three subdistricts per province, and 54 health facilities were selected by stratified random sampling. At each facility, 30 (or all if <30) patients diagnosed in Quarter 1 2009 were randomly selected for review. Patient information was evaluated across two paper and four electronic sources. Completeness of program indicators between paper and electronic sources was compared with chi-square tests. The kappa statistic was used to evaluate agreement of values.ResultsOver one-third (33.7 %) of all persons with presumptive TB recorded as smear positive in the TB Suspect Register did not have any records documenting notification, treatment, or management for TB disease. Of 1339 persons with a record as a TB patient at the facility, 1077 (80 %) were recorded in all data sources. Over 98 % of records contained complete age and sex data. Completeness varied for HIV status (53-86 %; p < 0.001) and DOT during the intensive phase of treatment (17-54 %; p < 0.001). Agreement for sex was excellent across sources (kappa 0.94); moderate for patient type (0.78), treatment regimen (0.79), treatment outcome (0.71); and poor for HIV status (0.33).ConclusionsThe current evaluation revealed that one-third of persons diagnosed with TB disease may not have been notified of their disease or initiated on treatment (‘initial defaulters’). The ETR is not capturing all TB patients. Further, among patients with a TB record, completeness and reliability of information in the TB Surveillance System is inconsistent across data sources. Actions are urgently needed to ensure that all diagnosed patients are treated and managed and improve the integrity of surveillance information.

BackgroundTuberculosis (TB) indicators in South Africa currently remain well below global targets. In 2008, the National Tuberculosis Program (NTP) implemented a community mobilization program in all nine provinces to trace TB patients that had missed a treatment or clinic visit. Implementation sites were selected by TB program managers and teams liaised with health facilities to identify patients for tracing activities. The objective of this analysis was to assess the impact of the TB Tracer Project on treatment outcomes among TB patients.MethodsThe study population included all smear positive TB patients registered in the Electronic TB Registry from Quarter 1 2007-Quarter 1 2009 in South Africa. Subdistricts were used as the unit of analysis, with each designated as either tracer (standard TB program plus tracer project) or non-tracer (standard TB program only). Mixed linear regression models were utilized to calculate the percent quarterly change in treatment outcomes and to compare changes in treatment outcomes from Quarter 1 2007 to Quarter 1 2009 between tracer and non-tracer subdistricts.ResultsFor all provinces combined, the percent quarterly change decreased significantly for default treatment outcomes among tracer subdistricts (−0.031%; p < 0.001) and increased significantly for successful treatment outcomes among tracer subdistricts (0.003%; p = 0.03). A significant decrease in the proportion of patient default was observed for all provinces combined over the time period comparing tracer and non-tracer subdistricts (p = 0.02). Examination in stratified models revealed the results were not consistent across all provinces; significant differences were observed between tracer and non-tracer subdistricts over time in five of nine provinces for treatment default.ConclusionsCommunity mobilization of teams to trace TB patients that missed a clinic appointment or treatment dose may be an effective strategy to mitigate default rates and improve treatment outcomes. Additional information is necessary to identify best practices and elucidate discrepancies across provinces; these findings will help guide the NTP in optimizing the adoption of tracing activities for TB control.

Introductory note by Alfredo MorabiaThis article closes the series of contributions on the history of epidemiologic methods and concepts. It traces, in some epidemiology textbooks published in the 20 th century, the evolution of the way five main topics have been taught: study designs (cohort studies and case-control studies), confounding, bias, interaction, and causal inference. These correspond to the topics covered by the other papers in the series. The only exception is the concept of interaction, for which I had not been able to find an author. This final paper has been sent to review and/or comment to all the living authors of the textbooks. Three authors opted for commentaries which are also published in this issue of Social and Preventive Medicine and two for reviews. Our publisher, Birkhäuser, has been kind enough to let us post the pdfs of all these papers on the website: www.epidemiology.ch (choose history). A revised version of these papers accompanied by a substantial introduction, pooled bibliography and index will appear in 2004 as a book entitled "The history of epidemiological methods and concepts" (Birkhäuser). SummaryTextbooks are an expression of the state of development of a discipline at a given moment in time. By reviewing eight epidemiology textbooks published over the course of a century, we have attempted to trace the evolution of five epidemiologic concepts and methods: study design (cohort studies and case-control studies), confounding, bias, interaction and causal inference. Overall, these eight textbooks can be grouped into three generations. Greenwood (1935) Miettinen (1985) and Rothman (1986)'s textbooks belong to a third generation, "modern epidemiology", presenting an integrated perspective on study designs and their measures of outcome, as well as distinguishing and formalizing the concepts of confounding and interaction. Our review demonstrates that epidemiology, as a scientific discipline, is in constant evolution and transformation. It is likely that new methodological tools, able to assess the complexity of the causes of human health, will be proposed in future generations of textbooks.

Background Standardised tuberculosis (TB) treatment through directly observed therapy (DOT) is available in South Africa, but the level of adherence to standardised TB treatment and its impact on treatment outcomes is unknown. Objectives To describe adherence to standardised TB treatment and provision of DOT, and analyse its impact on treatment outcome. Methods We utilised data collected for an evaluation of the South African national TB surveillance system. A treatment regimen was considered appropriate if based on national treatment guidelines. Multivariate log-binomial regression was used to evaluate the association between treatment regimens, including DOT provision, and treatment outcome. Results Of 1 339 TB cases in the parent evaluation, 598 (44.7%) were excluded from analysis owing to missing outcome or treatment information. The majority (697, 94.1%) of the remaining 741 patients received an appropriate TB regimen. Almost all patients (717, 96.8%) received DOT, 443 (59.8%) throughout the treatment course and 274 (37.0%) during the intensive (256, 34.6%) or continuation (18, 2.4%) phase. Independent predictors of poor outcome were partial DOT (adjusted risk ratio (aRR) 3.1, 95% confidence interval (CI) 2.2 – 4.3) and previous treatment default (aRR 2.3, 95% CI 1.1 – 4.8). Conclusion Patients who received incomplete DOT or had a history of defaulting from TB treatment had an increased risk of poor outcomes.

Introductory note by Alfredo MorabiaThis article closes the series of contributions on the history of epidemiologic methods and concepts. It traces, in some epidemiology textbooks published in the 20 th century, the evolution of the way five main topics have been taught: study designs (cohort studies and case-control studies), confounding, bias, interaction, and causal inference. These correspond to the topics covered by the other papers in the series. The only exception is the concept of interaction, for which I had not been able to find an author. This final paper has been sent to review and/or comment to all the living authors of the textbooks. Three authors opted for commentaries which are also published in this issue of Social and Preventive Medicine and two for reviews. Our publisher, Birkhäuser, has been kind enough to let us post the pdfs of all these papers on the website: www.epidemiology.ch (choose history). A revised version of these papers accompanied by a substantial introduction, pooled bibliography and index will appear in 2004 as a book entitled "The history of epidemiological methods and concepts" (Birkhäuser). SummaryTextbooks are an expression of the state of development of a discipline at a given moment in time. By reviewing eight epidemiology textbooks published over the course of a century, we have attempted to trace the evolution of five epidemiologic concepts and methods: study design (cohort studies and case-control studies), confounding, bias, interaction and causal inference. Overall, these eight textbooks can be grouped into three generations. Greenwood (1935) Miettinen (1985) and Rothman (1986)'s textbooks belong to a third generation, "modern epidemiology", presenting an integrated perspective on study designs and their measures of outcome, as well as distinguishing and formalizing the concepts of confounding and interaction. Our review demonstrates that epidemiology, as a scientific discipline, is in constant evolution and transformation. It is likely that new methodological tools, able to assess the complexity of the causes of human health, will be proposed in future generations of textbooks.