ABSTRACT
BACKGROUND: Active case finding (ACF) in household contacts of tuberculosis (TB) patients is now recommended for National TB Programs (NTP) in low- and middle-income countries. However, evidence supporting these recommendations remains limited. This study evaluates the effectiveness and cost-effectiveness of ACF for household contacts of TB cases in a large TB endemic district of Lima, Peru. METHODS: A pragmatic stepped-wedge cluster randomized controlled trial was conducted in 34 health centers of San Juan de Lurigancho district. Centers were stratified by TB rate and randomly allocated to initiate ACF in groups of eight or nine centers at four-month intervals. In the intervention arm, NTP providers visited households of index patients to screen contacts for active TB. The control arm was routine passive case finding (PCF) of symptomatic TB cases. The primary outcomes were the crude and adjusted active TB case rates among household contacts. Program costs were directly measured, and the cost-effectiveness of the ACF intervention was determined. FINDINGS: 3222 index TB cases and 12,566 household contacts were included in the study. ACF identified more household contact TB cases than PCF, 199.29/10,000 contacts/year vs. 132.13 (incidence rate ratio of 1.51 (95% CI 1.21-1.88)). ACF was associated with an incremental cost-effectiveness ratio of US $16,400 per disability-adjusted life year averted and not cost-effective assuming a willingness-to-pay threshold for Peru of US $6360. CONCLUSION: ACF of TB case household contacts detected significantly more secondary TB cases than PCF alone, but was not cost-effective in this setting. In threshold analyses, ACF becomes cost-effective if associated with case detection rates 2.5 times higher than existing PCF programs.
Subject(s)
Contact Tracing/economics , Tuberculosis/diagnosis , Adult , Cost-Benefit Analysis , Family Characteristics , Female , Humans , Male , Peru/epidemiologyABSTRACT
BACKGROUND: We designed a pragmatic stepped-wedge cluster randomized controlled trial in order to evaluate provider-initiated evaluation of household contacts (HCs) of smear positive tuberculosis (TB) cases within a routine TB program in Lima, Peru. METHODS/DESIGN: National TB program (NTP) officers of San Juan de Lurigancho District (Lima, Peru) and university-based researchers jointly designed a pragmatic stepped-wedge cluster randomized trial design in order to evaluate a planned active case finding (ACF) program for all HCs of smear-positive TB cases in 34 district healthcare centres. Randomization of time to intervention initiation was stratified by health centre TB case rate. The ACF intervention included provider-initiated home visits of all new sputum smear positive TB patients in order to evaluate household contacts for active TB. Active TB was diagnosed using symptom screening, sputum screening, chest x-ray and clinical evaluation. Once initiated, ACF was provided by NTP staff and integrated into the routine DOTS TB program activities. DISCUSSION: This study protocol describes the pragmatic stepped-wedge cluster randomized trial of active household contact evaluations within an NTP. The stepped-wedge design met overlapping needs of local TB programmers and researchers to adequately evaluate the large-scale roll out of a new control program in a TB endemic setting. Multiple planning meetings were required to develop the necessary networks and in order to understand the operations, needs and goals of the NTP staff and researchers collaborating on this project. The advantages and challenges of using this study design in practice and within existing routine TB programs in a middle-income country context are discussed. TRIAL REGISTRATION: ClinicalTrials.gov NCT02174380. Registered 24 Jun 2014.
