Evaluation of the tuberculosis notification impact from an intermediary-facilitated public–private mix intervention in Viet Nam: A population-level quasi-experimental study
12 affiliations
- 1Friends for International TB Relief, Ha Noi, Viet Nam
- 2Department of Global Public Health, Karolinska Institutet, Stockholm, Sweden
- 3University of Sydney Vietnam Institute, Ho Chi Minh City, Viet Nam
- 4Stop TB Partnership, Geneva, Switzerland
- 5National Lung Hospital, Ha Noi, Viet Nam
- 6Pham Ngoc Thach Hospital, Ho Chi Minh City, Viet Nam
- 7The Swedish Institute for Health Economics, Stockholm, Sweden
- 8United States Agency for International Development, Ha Noi, Viet Nam
- 9Global Fund to Fight AIDS, Tuberculosis and Malaria, Geneva, Switzerland
- 10Centre for Tuberculosis Research, Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- 11Tropical and Infectious Diseases Unit, Liverpool University Hospital NHS Foundation Trust, Liverpool, United Kingdom
- 12VNU University of Medicine and Pharmacy, Ha Noi, Viet Nam
Abstract
Background: Treatment coverage gaps remain a major barrier to ending tuberculosis (TB). Public–private mix (PPM) entails the engagement of healthcare providers outside of national TB programs (NTP). PPM strategies are promoted to improve TB notification, particularly in high-burden settings with fragmented care systems, and intermediary agencies are recognized as effective mechanisms to operationalize PPM by bridging NTPs and out-of-network healthcare providers. However, population-level evidence is rare, as most evaluations have been limited to pilot studies, small geographic areas, or uncontrolled designs. This study documents the population-level association of a PPM intervention with TB notifications through the use of unbiased analytical methods to account for heterogeneity from the intervention’s staggered deployment and dynamic intensity. Methods and findings: We present a non-randomized, quasi-experimental evaluation of a large-scale intermediary-facilitated PPM intervention conducted between 2020 and 2023 in 15 provinces of Viet Nam, covering 40.6 million people equivalent to 40% of the population. The intervention engaged 3,154 non-NTP providers in TB care, linking them to the NTP through systematic screening, referral, and reporting mechanisms. The model emphasized active case finding, provider incentives, patient support and integrated data systems to raise notifications as the primary outcome. We analyzed quarterly province-level TB notification data from 2016 to 2025 using a heterogeneity-robust extended two-way fixed-effects framework to estimate the average treatment effect on the treated. The analysis adjusted for province and calendar-quarter fixed effects, and for COVID-19 disruptions. Using Poisson pseudo-maximum-likelihood fixed-effects models, we estimated dose–response effects and post-intervention patterns and triangulated effects with an interrupted time-series analysis of national notifications and repeated all analyses using the intermediate outcome of PPM notifications. Lastly, we calculated marginal cost per additional notification from a funder perspective. The intervention was associated with 316.8 additional notifications per province-quarter (95% confidence interval [CI] [23.4, 610.2]; p = 0.034). Regarding dose–response effects, we observed a 1.4% increase in notifications per 100 verbal assessments per 100,000 population (incidence rate ratio [IRR]=1.00014; 95% CI [1.00002, 1.00025]; p = 0.018). National models suggested 3,206 (95% CI [1,658, 4,763]; p < 0.001) additional notifications annually with a 3.5% intensity-associated notification increase (IRR = 1.00035; 95% CI [1.00018, 1.00052]; p < 0.001). Using PPM notifications produced concordant results. The costs per additional notification were US$ 166-US$ 458. The main limitation was the non-randomized design, with high-burden provinces purposively selected as intervention areas. This was mitigated through conservative control selection and triangulation across methods. Conclusions: This study furnishes robust, policy-relevant evidence that intermediary-facilitated PPM implemented at scale in Viet Nam was associated with significant, dose–responsive increases in PPM and TB notifications at provincial and national levels. These findings promote intermediary agency models as an effective mechanism to operationalize PPM at scale and to generate public health benefits in closing TB treatment coverage gaps. In an era of constrained global health financing, leveraging existing provider networks through intermediary-facilitated PPM offers an affordable and scalable strategy to sustain momentum towards ending TB. Why was this study done?: What did the researchers do and find?: What do these findings mean?: Using a population-level quasi-experimental study design, Luan Nguyen Quang Vo and colleagues assess the effects of a public-private mix intervention implemented in Viet Nam and designed to increase tuberculosis notifications, with the aim that such approaches could ultimately increase treatment coverage.
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BibTeX
@article{vo2026evaluation,
title = {{Evaluation of the tuberculosis notification impact from an intermediary-facilitated public–private mix intervention in Viet Nam: A population-level quasi-experimental study}},
author = {Luan Nguyen Quang Vo and Thuy Thi Thu Dong and Huy Ba Huynh and Binh Anh Luong and Huong Thi Lan Mo and Andrew James Codlin and Rachel Forse and Thuy Doan To Mai and Lan Phuong Nguyen and Jacob Creswell and Luong Van Dinh and Hoa Binh Nguyen and Phu Xuan Vu and Tuan Dinh Nguyen and Lan Huu Nguyen and Thi Minh Ha Dang and Son Van Luu and Nam Hoang Do and Huyen Thanh Truong and Phan Do Nguyen and Tushar Garg and Jad Shedrawy and Kristi Sidney Annerstedt and Minh Huy Pham and Jamie Tonsing and Tom Wingfield and Mohammed Ahmed Yassin and Nhung Viet Nguyen and Knut Lönnroth},
journal = {PLOS Medicine},
year = {2026},
month = sep,
doi = {10.1371/journal.pmed.1005144},
url = {https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1005144},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Evaluation of the tuberculosis notification impact from an intermediary-facilitated public–private mix intervention in Viet Nam: A population-level quasi-experimental study
AU - Luan Nguyen Quang Vo
AU - Thuy Thi Thu Dong
AU - Huy Ba Huynh
AU - Binh Anh Luong
AU - Huong Thi Lan Mo
AU - Andrew James Codlin
AU - Rachel Forse
AU - Thuy Doan To Mai
AU - Lan Phuong Nguyen
AU - Jacob Creswell
AU - Luong Van Dinh
AU - Hoa Binh Nguyen
AU - Phu Xuan Vu
AU - Tuan Dinh Nguyen
AU - Lan Huu Nguyen
AU - Thi Minh Ha Dang
AU - Son Van Luu
AU - Nam Hoang Do
AU - Huyen Thanh Truong
AU - Phan Do Nguyen
AU - Tushar Garg
AU - Jad Shedrawy
AU - Kristi Sidney Annerstedt
AU - Minh Huy Pham
AU - Jamie Tonsing
AU - Tom Wingfield
AU - Mohammed Ahmed Yassin
AU - Nhung Viet Nguyen
AU - Knut Lönnroth
PY - 2026
DA - 2026/09/23
JO - PLOS Medicine
DO - 10.1371/journal.pmed.1005144
UR - https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1005144
AB - Background: Treatment coverage gaps remain a major barrier to ending tuberculosis (TB). Public–private mix (PPM) entails the engagement of healthcare providers outside of national TB programs (NTP). PPM strategies are promoted to improve TB notification, particularly in high-burden settings with fragmented care systems, and intermediary agencies are recognized as effective mechanisms to operationalize PPM by bridging NTPs and out-of-network healthcare providers. However, population-level evidence is rare, as most evaluations have been limited to pilot studies, small geographic areas, or uncontrolled designs. This study documents the population-level association of a PPM intervention with TB notifications through the use of unbiased analytical methods to account for heterogeneity from the intervention’s staggered deployment and dynamic intensity. Methods and findings: We present a non-randomized, quasi-experimental evaluation of a large-scale intermediary-facilitated PPM intervention conducted between 2020 and 2023 in 15 provinces of Viet Nam, covering 40.6 million people equivalent to 40% of the population. The intervention engaged 3,154 non-NTP providers in TB care, linking them to the NTP through systematic screening, referral, and reporting mechanisms. The model emphasized active case finding, provider incentives, patient support and integrated data systems to raise notifications as the primary outcome. We analyzed quarterly province-level TB notification data from 2016 to 2025 using a heterogeneity-robust extended two-way fixed-effects framework to estimate the average treatment effect on the treated. The analysis adjusted for province and calendar-quarter fixed effects, and for COVID-19 disruptions. Using Poisson pseudo-maximum-likelihood fixed-effects models, we estimated dose–response effects and post-intervention patterns and triangulated effects with an interrupted time-series analysis of national notifications and repeated all analyses using the intermediate outcome of PPM notifications. Lastly, we calculated marginal cost per additional notification from a funder perspective. The intervention was associated with 316.8 additional notifications per province-quarter (95% confidence interval [CI] [23.4, 610.2]; p = 0.034). Regarding dose–response effects, we observed a 1.4% increase in notifications per 100 verbal assessments per 100,000 population (incidence rate ratio [IRR]=1.00014; 95% CI [1.00002, 1.00025]; p = 0.018). National models suggested 3,206 (95% CI [1,658, 4,763]; p < 0.001) additional notifications annually with a 3.5% intensity-associated notification increase (IRR = 1.00035; 95% CI [1.00018, 1.00052]; p < 0.001). Using PPM notifications produced concordant results. The costs per additional notification were US$ 166-US$ 458. The main limitation was the non-randomized design, with high-burden provinces purposively selected as intervention areas. This was mitigated through conservative control selection and triangulation across methods. Conclusions: This study furnishes robust, policy-relevant evidence that intermediary-facilitated PPM implemented at scale in Viet Nam was associated with significant, dose–responsive increases in PPM and TB notifications at provincial and national levels. These findings promote intermediary agency models as an effective mechanism to operationalize PPM at scale and to generate public health benefits in closing TB treatment coverage gaps. In an era of constrained global health financing, leveraging existing provider networks through intermediary-facilitated PPM offers an affordable and scalable strategy to sustain momentum towards ending TB. Why was this study done?: What did the researchers do and find?: What do these findings mean?: Using a population-level quasi-experimental study design, Luan Nguyen Quang Vo and colleagues assess the effects of a public-private mix intervention implemented in Viet Nam and designed to increase tuberculosis notifications, with the aim that such approaches could ultimately increase treatment coverage.
SN - 1549-1676
ER -