Cost-effectiveness of rapid diagnostic tests, compared to microscopic tests, for the diagnosis and treatment of gestational malaria in Colombia from an institutional perspective.

BACKGROUND: Gestational malaria is associated with negative outcomes in maternal and gestational health; timely diagnosis is crucial to avoid complications. However, the limited infrastructure, equipment, test reagents, and trained staff make it difficult to use thick blood smear tests in rural areas, where rapid testing could be a viable alternative. The purpose of this study was to estimate the cost-effectiveness of rapid tests type III (Plasmodium falciparum/Plasmodium spp P.f/pan) versus microscopic tests for the diagnosis and treatment of gestational malaria in Colombia. METHODS: Cost-effectiveness analyses of gestational malaria diagnosis from an institutional perspective using a decision tree. Standard costing was performed for the identification, measurement and assessment phases, with data from Colombian tariff manuals. The data was collected from Health Situation Analysis, SIVIGILA and meta-analysis. Average and incremental cost-effectiveness ratio were estimated. The uncertainty was assessed through probabilistic sensitivity analysis. RESULTS: The cost of rapid diagnostic tests in 3,000 pregnant women with malaria was US$66,936 and 1,182 disability adjusted life years (DALYs) were estimated. The cost using thick blood smear tests was US$50,838 and 1,023 DALYs, for an incremental cost-effectiveness of US$ 101.2. The probabilistic sensitivity analysis of rapid diagnostic tests determined that they are highly cost-effective in 70% of the cases, even below the US$1,200 threshold; also, they showed an incremental net monetary benefit of $150,000 when payer's willingness is US$1,000. CONCLUSION: The use of rapid diagnostic tests for timely diagnosis and treatment of gestational malaria is a highly cost-effective strategy in Colombia, with uncertainty analyses supporting the robustness of this conclusion and the increased net monetary benefit that the health system would obtain. This strategy may help in preventing the negative effects on maternal health and the neonate at a low cost.

Systematic review of microeconomic analysis of pregnancy-associated malaria.

INTRODUCTION: Pregnancy-associated malaria (PAM) is a health problem with serious clinical, epidemiological and economic effects. PURPOSE: To analyze the microeconomic evaluations of PAM reported in the world scientific literature. METHODS: Systematic review with 15 different search strategies in PubMed, ScienceDirect, Scielo, Google Scholar and Malaria in Pregnancy (MiP) Library. A search, selection and extraction protocol was applied, which guaranteed completeness and reproducibility in accordance with preferred reporting items for systematic reviews and meta-analysis guidelines. The methodological quality was evaluated using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) guide. The analysis were based on frequencies, costs and average and incremental cost-effectiveness ratios in 2018 US dollars adjusted for purchasing power parity. RESULTS: Twenty-two evaluations published between 1990 and 2018 were analyzed, of which 82% addressed cost-effectiveness in Africa. Twelve interventions were studied; of these, intermittent preventive treatment in pregnant women with sulfadoxine-pyrimethamine (IPTp-SP) was the most frequent strategy. The main outcomes were low birth weight, anaemia and DALYs avoided. The best average cost-effectiveness ratio was reported in IPTp-SP with a cost of US$ 2 per DALY avoided, followed by the administration of IPTp-SP in pregnant women with HIV (US$ 14.2). CONCLUSIONS: The studies focus on Africa with a high heterogeneity in the interventions, outcomes, resources and populations studied. All the interventions were highly cost-effective, which demonstrates the importance of including prevention, care and control resources for PAM as a priority in health sector budgets. This is especially true considering the importance of its intervention for social progress and overcoming poverty in endemic areas.

Costo-efectividad de pruebas para el diagnóstico de geohelmintiasis: Revisión sistemática de la literatura / Cost-effectiveness of diagnostic tests in soil-transmitted helminth infections: a systematic review of literature

Introducción: Existen diversas pruebas para el diagnóstico de las geohelmintiasis, con múltiples estudios que demuestran la heterogeneidad en su validez diagnóstica y pocos que aluden su costo-efectividad. Objetivo: Sistematizar las evaluaciones económicas sobre las pruebas aplicadas en el diagnóstico de geohelmintos. Métodos: Revisión sistemática en seis bases de datos con 24 estrategias de búsqueda. Se aplicó un protocolo de selección de estudios, garantizando exhaustividad, reproducibilidad y evaluación de la calidad metodológica. Se realizó síntesis cualitativa de la información. Resultados: En la literatura científica mundial sólo se dispone de cuatro evaluaciones económicas completas para el diagnóstico de geo-helmintos, en la modalidad de estudios de costo-efectividad; en éstas se evaluaron cinco pruebas en 247 adultos y 6.708 niños. En los desenlaces en salud empleados se encontraron la proporción de pacientes positivos y algunos parámetros de validez diagnóstica como la sensibilidad y la especificidad, mientras que los costos se circunscribieron a insumos y salarios. Estos hallazgos ponen de manifiesto la baja aplicación de los recursos teóricos y metodológicos de la economía de la salud en el diagnóstico de las geohelmintiasis. Conclusión: Las evaluaciones económicas de pruebas para el diagnóstico de geohelmintos y parásitos intestinales en general son exiguas en el ámbito mundial y los pocos estudios disponibles presentan limitaciones de validez interna y externa que impiden la aplicación de sus resultados a otros ámbitos.

Introduction: The tests for diagnosis of the geohelmintiasis are diverse, with multiple studies that demonstrate heterogeneity in its diagnostic validity and few about its cost-effectiveness. Objective: To systematize the economic evaluations on the tests applied in the diagnosis of geohelminths. Methods: Systematic review in six databases with 24 search strategies. A protocol for the selection of the studies was applied, guaranteeing completeness, reproducibility and evaluation of methodological quality. Qualitative synthesis of the information was made. Results: In the scientific literature there are four complete economic evaluations (cost-effectiveness studies) for the diagnosis of geo-helminths; in these, five tests were evaluated in 247 adults and 6,708 children. In the health outcomes the studies employed the proportion of positive patients and some diagnostic validity parameters such as sensitivity and specificity, while costs were limited to inputs and salaries. These findings show the low application of the theoretical and methodological resources of health economics in the diagnosis of soil-transmitted helminth infections. Conclusion: The economic evaluations of tests for the diagnosis of geohelminths and intestinal parasites in general are meager worldwide and the few available studies have limitations of internal and external validity that prevent the application of their results to other areas.

[Validity of three methods for inmuno-diagnostic of neurocysticercosis: systematic review of the literature with meta-analysis 1960-2014]. / Validez de tres métodos de inmuno-diagnóstico de neurocisticercosis: revisión sistemática de la literatura con meta-análisis 1960-2014.

INTRODUCTION: The screening of neurocysticercosis is complex and immunological methods have varying validity. OBJECTIVE: To evaluate the validity of ELISA for antigen and antibody, and EITB for antibody in the screening of neurocysticercosis. METHODS: Meta-analysis of diagnostic tests with an ex-ante protocol implemented in five databases with 15 search strategies, ensuring reproducibility in the selection and extraction of information. Sensitivity, specificity, likelihood ratios (LR), diagnostic odds ratio and ROC curve were estimated in MetaDiSc, and predictive values, and Youden index were estimated in Epidat. RESULTS: EITB presented sensitivity of 85.7% (95% CI 83.5-87.7), specificity 93.9% (95% CI = 92.7-95.0), PLR 19.6 (95% CI = 8,6-44.6), NLR 0.16 (95% CI = 0.12-0.21), OR diagnostic 136.2 (95% CI = 54.7-342.6) and area under the curve 0.926. In ELISA for antibody sensitivity was 87.5% (95% CI = 86.1-88.8), specificity 92.2% (95% CI = 91.4-93.0), PLR 11.3 (95% CI = 8.45-15.11), NLR 0.15 (95% CI = 0.13-0.18), diagnostic OR 87.4 (95% CI = 60.1-127.1) and area under the curve 0.950. ELISA for antigen showed low diagnostic validity. No differences were found in these parameters by sample, antigen or antibody type. CONCLUSION: ELISA for antibodies and EITB have a similar diagnostic value, detection of serum and CSF showed a similar validity.

Validez de tres métodos de inmuno-diagnóstico de neurocisticercosis: revisión sistemática de la literatura con meta-análisis 1960-2014 / Validity of three methods for inmuno-diagnostic of neurocysticercosis: systematic review of the literature with meta-analysis 1960-2014

Introduction: The screening of neurocysticercosis is complex and immunological methods have varying validity. Objective: To evaluate the validity of ELISA for antigen and antibody, and EITB for antibody in the screening of neurocysticercosis. Methods: Meta-analysis of diagnostic tests with an ex-ante protocol implemented in five databases with 15 search strategies, ensuring reproducibility in the selection and extraction of information. Sensitivity, specificity, likelihood ratios (LR), diagnostic odds ratio and ROC curve were estimated in MetaDiSc, and predictive values, and Youden index were estimated in Epidat. Results: EITB presented sensitivity of 85.7% (95% CI 83.5-87.7), specificity 93.9% (95% CI = 92.7-95.0), PLR 19.6 (95% CI = 8,6-44.6), NLR 0.16 (95% CI = 0.12-0.21), OR diagnostic 136.2 (95% CI = 54.7-342.6) and area under the curve 0.926. In ELISA for antibody sensitivity was 87.5% (95% CI = 86.1-88.8), specificity 92.2% (95% CI = 91.4-93.0), PLR 11.3 (95% CI = 8.45-15.11), NLR 0.15 (95% CI = 0.13-0.18), diagnostic OR 87.4 (95% CI = 60.1-127.1) and area under the curve 0.950. ELISA for antigen showed low diagnostic validity. No differences were found in these parameters by sample, antigen or antibody type. Conclusion: ELISA for antibodies and EITB have a similar diagnostic value, detection of serum and CSF showed a similar validity.

Introducción: La tamización de neurocisticercosis es compleja y los métodos inmunológicos presentan validez variable y generalmente bajos tamaños de muestra. Objetivo: Evaluar la validez de ELISA para detección de antígeno y anticuerpo, y EITB para detección de anticuerpo en la tamización de neurocisticercosis. Métodos: Meta-análisis de pruebas diagnósticas con un protocolo ex-ante aplicado en cinco bases de datos con 15 estrategias de búsqueda, garantizando reproducibilidad en la selección y extracción de la información. Se estimó sensibilidad, especificidad, cocientes de probabilidad (CP), razón de odds diagnósticas y curva ROC en MetaDiSC, y valores predictores, índice de Youden y exactitud en Epidat. Resultados: EITB presentó sensibilidad de 85,7% (IC 95% = 83,5-87,7), especificidad 93,9% (IC9 5% = 92,7-95,0), CPP 19,6 (IC 95% = 8,6-44,6), CPN 0,16 (IC 95% = 0,12-0,21), OR diagnóstica 136,2 (IC 95% = 54,7-342,6) y área bajo la curva 0,926. En ELISA para anticuerpos la sensibilidad fue 87,5% (IC 95% = 86,1-88,8), especificidad 92,2% (IC 95% = 91,4-93,0), CPP 11,3 (IC 95% = 8,45-15,11), CPN 0,15 (IC 95% = 0,13-0,18), OR diagnóstica 87,4 (IC 95% = 60,1-127,1) y área bajo la curva 0,950. ELISA para antígeno presentó baja validez diagnóstica. No se hallaron diferencias en estos parámetros según tipo de muestra, antígeno o anticuerpo. Conclusión: ELISA para anticuerpos y EITB presentan una utilidad diagnóstica similar, la detección de suero presentó una validez similar al líquido cefalorraquídeo.