Limitations of the UNAIDS 90-90-90 Metrics: A Simulation-Based Comparison of Cross-Sectional and Longitudinal Metrics for the HIV Care Continuum

Citation

Haber, Noah; Lesko, Catherine R.; Fox, Matthew P.; Powers, Kimberly A.; Harling, Guy; Edwards, Jessie K.; Salomon, Joshua A.; Lippman, Sheri A.; Bor, Jacob; & Chang, Angela Y., et al. (2020). Limitations of the UNAIDS 90-90-90 Metrics: A Simulation-Based Comparison of Cross-Sectional and Longitudinal Metrics for the HIV Care Continuum. AIDS, 34(7), 1047-1055. PMCID: PMC7253182

Abstract

OBJECTIVES: The UNAIDS 90-90-90 and other cross-sectional metrics can lead to potentially counterintuitive conclusions when used to evaluate health systems' performance. This study demonstrates how time and population dynamics impact UNAIDS 90-90-90 metrics in comparison with a longitudinal analogue.
DESIGN: A simplified simulation representing a hypothetical population was used to estimate and compare inference from UNAIDS 90-90-90 metrics and a longitudinal metrics based on Kaplan-Meier-estimated 2-year probability of transition between stages.
METHODS: We simulated a large cohort over 15 years. Everyone started out at risk for HIV, and then transitioned through the HIV care continuum based on fixed daily probabilities of acquiring HIV, learning status, entering care, initiating ART, and becoming virally suppressed, or dying. Within simulations we only varied the probability of ART initiation. We repeated the simulation with an increased probability of death.
RESULTS: The cross-sectional probability of being on ART among persons who were diagnosed responded relatively slowly to changes in the rate of ART initiation. Increases in ART initiation rates caused apparent declines in the cross-sectional probability of being virally suppressed among persons who had initiated ART, despite no changes in the rate of viral suppression. In some cases, higher mortality resulted in the cross-sectional metrics implying improved healthcare system performance. The longitudinal continuum was robust to these issues.
CONCLUSION: The UNAIDS 90-90-90 care continuum may lead to incorrect inference when used to evaluate health systems performance. We recommend that evaluation of HIV care delivery include longitudinal care continuum metrics wherever possible.

URL

http://dx.doi.org/10.1097/QAD.0000000000002502

Reference Type

Journal Article

Year Published

2020

Journal Title

AIDS

Author(s)

Haber, Noah
Lesko, Catherine R.
Fox, Matthew P.
Powers, Kimberly A.
Harling, Guy
Edwards, Jessie K.
Salomon, Joshua A.
Lippman, Sheri A.
Bor, Jacob
Chang, Angela Y.
Anglemyer, Andrew
Pettifor, Audrey E.

Article Type

Regular

PMCID

PMC7253182

Continent/Country

Nonspecific

ORCiD

Pettifor - 0000-0002-3387-0817
Haber - 0000-0002-5672-1769
Edwards, J -0000-0002-1741-335X