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Beyond 80%: The Effect of Conditional Cash Transfers on Vaccination Coverage in Mexico and Nicaragua. Tania Barham Institute of Behavior Science Department of Economics University of Colorado at Boulder Logan Brenzel HNP, World Bank John A. Maluccio Department of Economics
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Beyond 80%: The Effect of Conditional Cash Transfers on Vaccination Coveragein Mexico and Nicaragua Tania Barham Institute of Behavior Science Department of Economics University of Colorado at Boulder Logan Brenzel HNP, World Bank John A. Maluccio Department of Economics Middlebury College We would like to thank the Government of The Netherlands, through the World Bank-Netherlands Partnership Program for their generous support
Background: Global Vaccination Coverage • 1977: smallpox eradicated • 1988: polio eradication efforts began and are on-going (<2000 cases worldwide) • Mid 1990s: 75% of children were vaccinated against major childhood diseases globally • Eradicating measles may be the next challenge • Coverage rates close to 95 percent are needed.
Background: Global Vaccination Coverage Nevertheless … • 2 million children die each year from vaccine preventable diseases • 28 million inadequately protected • Coverage rates for the third dose of DPT3 to plateau below 90 percent for many regions DPT = Diptheria-Pertussis-Tetanus
100 90 80 70 60 50 40 30 20 10 0 2002 1986 1988 1990 1992 1994 1996 1998 2004 1980 1982 1984 2000 Sub-Saharan Africa Latin America and the Caribbean Mid-East and N. Africa Central Europe, CIS Southeast Asia East Asia and Pacific Global Trends in Coverage For DPT3 Source: WHO, 2006, Presentation “Estimated Coverage By Country, Year and Vaccine”, (http://www.who.int/immunization_monitoring/data/SlidesGlobalImmunization.pdf)
Outline • Standard approach to vaccination • Conditional cash transfers as an alterative • Program description: Mexico and Nicaragua • Data • Methods: Double Difference Estimator • Results • Policy conclusions
Vaccination: Standard Approach • Largely supply driven • Provide vaccines at health clinics • Vaccination campaign days • Bring vaccines to the community or often to house • Demand-side: focuses on awareness raising • Potential problem as near complete coverage • Theoretical model: Geoffard and Philipson (1997) • Due to positive externalities vaccination demand is negatively correlated with disease prevalence • Need for a demand incentive
Conditional Cash Transfers (CCTs):An Alternative Approach? • Aim is to build human capital of the poor and break the inter-generational transfer of poverty • Provide cash transfers conditional on receiving services (e.g. education, health, or nutrition) • Links transfers and public services • Are in many countries now: Argentina, Brazil, Colombia, Honduras, Jamaica, Mexico, Nicaragua, Mozambique, Turkey, US, Yemen
Conditional Cash Transfers (CCTs):An alternative approach Cont. • Provide incentive (cash) to households to take children to regular preventative health visits – which include vaccinations • Typically also include increase in supply of health services (e.g., introduction mobile clinics) • ensure targeted population able to receive the care for conditionalities. • keep quality of services from deteriorating when utilization increases • Other studies on CCT and Vaccinations • Morris, et al. 2004
Research Questions 1. Did the Mexican and Nicaraguan pilot CCT programs increase vaccination coverage for children under age 3? • Mexican program: Progresa/Oportunidades • Nicaraguan program: Red de Protección Social (RPS) 2. For which sub-groups of the population did the program have the largest impact?
Preview of results • Use random experiments • Rates above 95% for most vaccines • Increased overall coverage • Mexico: Measles 3 percentage point (pp) after a year (insignificant) • Nicaragua: 20 pp after a year, 12 pp after 2 years • Larger and significant increases for hard to reach populations • Mothers with less education • Live further from a health facility
Progresa: The Program • Transfers conditional on education, health, nutrition • Health conditionalities for children under age 5: • mandatory preventative health visits (include vaccinations) • 0-2 (11 visits total), 2-4 (3 visits a year) • Attend health education workshops • Transfers conditional on attendance, not vaccination status • Transfer given to mothers every other month • Size of transfer approximately 20% of household expenditures • Transfer for health and nutrition: $15.5/month per family
Progresa: Health Services • Used Ministry of Health services • Permanent clinics and mobile clinics • Mobile clinics visited communities on planned dates • May have been an increase in staff and mobile clinics • Services include growth monitoring, anti-parasite treatment, nutrition supplementation, treatment for respiratory infection, diarrhea, tuberculosis, and vaccinations.
Progresa: Randomized Evaluation • Randomized 506 rural villages in 7 states into 320 treatment and 186 control villages. • Only poor households were eligible • Treatment area eligible in 1998, control area in 2000 • Program participation over 90 percent
RPS: The Program • Transfers conditional on education, health, nutrition • Health conditionalities for children under age 5: • mandatory preventative health visits (include vaccinations) • < 2 (24 visits total), 2-5 (6 visits a year) • Attend health education workshops • Transfers conditional on attendance, not vaccination status • Transfer given to mothers every other month • Size of transfer averaged 13-21% of baseline household expenditures • Transfer for health and nutrition: $18/month per family
RPS: Health Services • Health Care Delivery • Contracted and trained private health providers • Providers visited communities on pre-planned dates • Delivered services in existing health clinics, community centers, or private homes • Services includegrowth monitoring, anti-parasite treatment, vitamin and iron supplementation, and (surprise!) vaccinations • Health services became available in June 2001, 6 months after the program started.
RPS: Randomized Evaluation • Randomized intervention at locality level (21 treatment, 21 control) in 6 rural municipalities • Treatment area eligible in 2001, control area in 2003 • Program participation over 90 percent Localities include 1-5 communities and average 100 households.
Data: Mexico • Progresa Evaluation Surveys • Baseline in May 1998, post-baseline May 1999 • Measures impact 12 months after baseline • 11,571 observations < age 3 (7,199 treatment)
Data: Nicaragua • RPS Evaluation Surveys • Baseline in Aug/Sept 2000, post-baseline Oct. 2001 and Oct. 2002. • Measures impact 5 and 17 months after health services introduced • 2,229 observations < age 3 (half in treatment) • Administrative Data • 2000-04 in treatment areas, 2003-04 in control areas • Complete vaccination history • available for control children < 2 in 2000. • Higher quality: collected by trained professionals • 9,986 children under age 3
Methods: Dependent Variables • Tuberculosis (BCG) • single dose, birth • Measles (MCV) • single dose, 12 months • Diphtheria-Pertussis-Tetanus (DPT3)–Only Nicaragua • 3 doses, 2, 4 and 6 months • Oral polio (OPV3)–Only Nicaragua • 3 doses, 2, 4 and 6 months • Fully vaccinated child (FVC) – Only Nicaragua • received all vaccines
Methods: Analysis Age Groups • On-time • <12 months: BCG • 12-23 months: MCV, DPT3, OPV3, FVC • Catch-Up • 12-23 months: BCG • 24-35 months: MCV, DPT3, OPV3, FVC
Methods Cont. • Intent-to-Treat Double-Difference Effect
Econometric Model: Double Difference Vicmt = ß12001t + ß22002t + δ1Tc *2001t + δ2Tc *2002t + µm + X’λ + εicmt • i = child c = locality m=municipality t=year • V = 1 if child i vaccinated zero otherwise • 2001 = 1 if year is 2001 and zero otherwise • 2002 = 1 if year is 2002 and zero otherwise • T = 1 if in treatment area and 0 in control area • μm = municipality-level fixed effect • X = baseline individual, parental, and household variables • ε = unobserved idiosyncratic error • Standard errors clustered at the locality level • Use linear probability models (OLS) because rates reach 100 % for some subgroups; results similar with logit or probit models
On-Time and Catch-Up Vaccinations Mexico No. of observations of all surveys:<12 mths=5701 12-23 mths=7018 24-35 mths=6328 ** Significant at 1 % level, * significant at 5 % level, + significant at 10 % level
On Time Vaccination, MCV Mexico ** Significant at 1 % level, * significant at 5 % level, + significant at 10 % level
On-Time Vaccination: Nicaragua No. Observations over all surveys: <12 mths =654 12-23 mths =759 ** Significant at 1 % level, * significant at 5 % level, + significant at 10 % level
On-Time Vaccination: Nicaragua No. Observations over all surveys: <12 mths =654 12-23 mths =759 ** Significant at 1 % level, * significant at 5 % level, + significant at 10 % level
On-Time Vaccination Using Admin Data No. Observations over all surveys: <12 mths =4596 12-23 mths =5390 ** Significant at 1 % level, * significant at 5 % level, + significant at 10 % level
On Time Vaccination, Full CoverageNicaragua ** Significant at 1 % level, * significant at 5 % level, + significant at 10 % level
Catch-Up Vaccination: Nicaragua No. Observations over all surveys: 12-23 mths =759 24-35 mths = 812 ** Significant at 1 % level, * significant at 5 % level, + significant at 10 % level
Robustness Considerations • Measurement Error (Nicaragua) • Results similar if condition on showing vaccination card. • Two different data sources • Concerns about systematic measurement error mitigated using high quality administrative data
Robustness Consideration • Increase in coverage in control areas • Spill-over effects: did not find effects (Nicaragua) • Strengthening of Ministry of Health through program • leads to better delivery of vaccines? • lead to increase supply in pilot areas? • No detailed supply data available • Government resources freed up in treatment area due to private delivery go to control areas? (Nicaragua) • Conservative results?
Summary • Rates were close to or greater than 95 % for BCG, OPV3 and DPT3 • Nicaragua: OPV3 and DPT3 were below 90% for country as a whole in 2005. • Mexico: • Small effects • due to high baseline levels of vaccination • Equalize rates between treatment and control areas
Summary Cont. • Nicaragua: • By 2002: significant increases of more than 12 pp for on-time and catch-up FVC • Effects larger for harder to reach populations • Mothers less educated at baseline • Further from a health clinic • Equalized coverage across subgroups
Limitations • Cannot identify demand vs supply effects (note: both components necessary) • Increase in control areas are not fully understood • Comparison area may be controlling for some increase in supply • Difficult to make cost comparisons given integrated nature of program • Don’t know program sustainability when cash transfers stop
Public Policy Relevance • Role for demand-incentives in vaccination policy • High vaccination levels achieved quickly • Reach populations that may be missed by traditional methods • Effects in middle- and low- income countries • Possible Future Directions • Demand-side incentive just for vaccinations • Need better information on the supply-side to isolate demand effect • Cost-benefit analysis