Tuberculosis care: an evaluability study

OBJECTIVE: to verify whether the tuberculosis control program (TCP) is evaluable and to examine the feasibility of building an evaluation model in apriority municipality for the control of tuberculosis. METHOD: this evaluability study was conducted in a municipality in northeastern Brazil. For data collection, documental analysis and interviews with key informants were performed. For indicator validation, the nominal group technique was adopted. RESULTS: the details of TCP were described, and both the logical model and the classification framework for indicators were developed and agreed up on, with the goal of characterizing the structural elements of the program, defining the structure and process indicators, and formulating the evaluation questions. CONCLUSION: TCP is evaluable. Based on logical operational analysis, it was possible to evaluate the adequacy of the program goals for the control of tuberculosis. Therefore, the performance of a summative evaluation is recommended, with a focus on the analysis of the effects of tuberculosis control interventions on decreasing morbidity and mortality.


Introduction
In the last decade, the incidence and mortality rates of tuberculosis (TB) have decreased in the six geographical regions defined by the World Health Organization (WHO) and in most of the 22 countries that account for 80% of TB cases worldwide, among which Brazil occupies the 19 th position. TB represents a serious public health problem, with approximately 9 million new cases and 1.5 million deaths each year (1) . In Brazil, TB kills 4500 people annually and is the leading cause of death among HIV/AIDS patients (2) . Despite the reduction in the number of cases in Brazil, the incidence rates have increased substantially among vulnerable population groups living in large cities (3) .
TB has assumed the status of a global emergency (1) and has been included in the government's policy agenda in several countries. To achieve the goal of decreasing the global burden of TB (incidence and mortality) by up to 50% by 2015 in comparison with the 1990 rate, the Ministry of Health of Brazil-through the National Tuberculosis Control Program (NTCP) and guided by the STOP-TB strategy-has endorsed the implementation and sustainability of the directly observed treatment short-course (DOTS) to improve laboratory diagnosis, conduct supervised treatments with the continuous supply of drugs, and develop an adequate information and registry system for program monitoring (2,(4)(5)(6) .
In conjunction with the national primary health care policy, the NTCP aims to intensify the decentralization of activities associated with the diagnosis and treatment of TB in primary health care since 2006. Furthermore, it aims to strengthen social control mechanisms and ensure the sustainability of disease control actions (2) .
Considering the epidemiological complexity of TB and the challenges imposed on the health care system and services for the eradication of the disease in the 21 st century, the evaluation of the tuberculosis control program (TCP) preceded by an evaluability study (ES) becomes relevant. In this context, ES is an important procedure to determine the feasibility of a systematic evaluation of TCP performance (7) . Internationally, the use of ES in different programs, disciplines, and contexts is evident (8) . A previous study conducted in Canada (9) examined the feasibility of evaluating a program for survivors of torture. With regard to tuberculosis, the use of a logical model of the community action program for the prevention of TB in public health in Ontario, Canada, was mentioned when reporting the use of an intervention based on the Ottawa Charter for Health Promotion (10) .
In Brazil, studies on public health are scarce.
Relevant studies include topics on human resource policies (11) and women's health (12) . Studies focused on tuberculosis include the evaluation of TB control interventions established in Niterói, Rio de Janeiro (13) , and in the legal Amazon (14) . Therefore, this study aimed to verify whether the TCP is evaluable, verify the feasibility of building an evaluation model of the program, and propose recommendations for future evaluation studies.

Methods
This evaluability study or pre-evaluation ( Evaluability studies are essential to the description of specific programs by identifying goals, objectives, and actions; structuring the logical models based on resources, activities, expected impacts, and possible correlations between program components; formulating evaluative questions; designing evaluation models; identifying the entities involved or interested in the evaluations (9) ; and proposing recommendations to the program and identifying the relevance of implementing such evaluations.
A logical model was developed to systematically identify the issues underlying the TCP by detailing the resources, activities, expected results, and correlations between these elements (7) . During the process of defining the logical model, it is important to review it and, if necessary, to readjust it to incorporate new aspects that were not previously addressed in its initial conception, with the goal of making it a valuable tool when defining the focus of the evaluation (15) .  (17) .
After building the logical model, the classification framework for indicators was elaborated, and its criteria and indicators were identified using the nominal group

Results
The diversity of organizational characteristics of access to tuberculosis diagnosis affect the proper management of the disease (20) in local health services and strengthen the performance of evaluation studies centered in the operational aspects (2)  The classification framework for indicators ( Figure 2) was constructed considering that a program evaluation should be based on parameters (15) and, for -Implementation of processes for TBcontinuing education, emphasizing the offering of courses on the diagnosis and treatment of TB.
-Conducting forums, seminars, and workshops to discuss improvements in TB control.
-Technical support to health units for the promotion of TB control actions in the community.
-Community mobilization to promote the coordination with formal social control authorities.
-Development and implementation of projects in health education and social communication and mobilization, with a focus on early diagnosis, treatment adherence, and fighting against discrimination.
-Production of educational and informative material for the dissemination of promotional and preventive actions on TB.

Discussion
This study highlights the need to incorporate new activities into the political and institutional context to meet internationally established goals (1) , with an emphasis on the effective decentralization of intervention strategies for family health care. The logical model can be used as a tool for the assessment and monitoring of the program and to evaluate its effects (21)(22) . Accordingly, the elements addressed in Using the classification framework for indicators comprising criteria, indicators, and previously developed standards, it is possible to assess TCP to verify whether the intervention results are being achieved as planned and are reaching the target population (13) . Moreover, evaluation questions are decisive for the success of the evaluation by defining what topics will be evaluated in conjunction with the focus of the evaluation (15) .

Conclusion
The tuberculosis control program is an evaluable program when considering its structural elements.