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Dr. Esther Duflo, Nobel Laureate in Economics, and co-founder and co-director of the Abdul Latif Jameel Poverty Action Lab (J-PAL) sat down with Dr. Benjamin Cook for a "fireside chat" at the 12th National Institute of Mental Health Global Mental Health Research Without Borders Conference. Dr. Duflo discussed J-PAL's efforts to develop and test interventions for improving mental health and how cash transfer programs can be used to improve mental health. She also discussed the importance of using randomized control trials (RCTs) in shaping global mental health initiatives. Dr. Duflo shared insights from projects addressing loneliness among older individuals in India, secondary school scholarships in Ghana, and other studies that have informed social policies. Looking forward, she discusses climate change as a threat to the reductions in poverty realized in the last 30 years and encourages the expansion of networks of research and policy collaborations to improve global health.
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Salud Global , Salud Mental , Humanos , Pobreza , Cambio ClimáticoRESUMEN
BACKGROUND: A growing number of older persons in developing countries live entirely alone and are physically, mentally, and financially vulnerable. OBJECTIVE: To determine whether phone-based cognitive behavioral therapy (CBT) or a cash transfer reduce functional impairment, depression, or food insecurity in this population. DESIGN: Randomized controlled trial. (ClinicalTrials.gov: NCT04225845; American Economic Association RCT Registry: AEARCTR-0007582). SETTING: Tamil Nadu, India, 2021. PARTICIPANTS: 1120 people aged 55 years and older and living alone. INTERVENTIONS: A 6-week, phone-based CBT and a 1-time cash transfer of 1000 rupees (U.S. $12 at market exchange rates) were evaluated in a factorial design. MEASUREMENTS: The World Health Organization Disability Assessment Schedule (WHODAS), the Geriatric Depression Scale, and food security, all measured 3 weeks after CBT for 977 people and 3 months after for 932. Surveyors were blind to treatment assignment. RESULTS: The WHODAS score (scale 0 to 48, greater values representing more impairment) decreased between baseline and the 3-week follow-up by 2.92 more (95% CI, -5.60 to -0.23) in the group assigned cash only than in the control group, and the depression score (ranging from 0 to 15, higher score indicating more depressive symptoms) decreased by 1.01 more (CI, -2.07 to 0.06). These effects did not persist to the 3-month follow-up, and CBT alone and the 2 together had no significant effects. There were no effects on food security. LIMITATIONS: The study cannot say whether more sustained or in-person therapy would have been effective, how results would translate outside of the COVID-19 period, or whether results in the consented sample differ from those in a larger population. Primary outcomes were self-reported. CONCLUSION: Among older people living alone, a small cash transfer was effective in alleviating short-term (3 weeks) functional impairment, produced a small but not clinically or statistically significant reduction in depression, and had no effect on food security. There were no short-term effects from CBT or the 2 interventions together. None of the interventions showed any effect at 3 months. PRIMARY FUNDING SOURCE: National Institute on Aging (NIA).
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COVID-19 , Terapia Cognitivo-Conductual , Humanos , Anciano , Anciano de 80 o más Años , India , Ambiente en el Hogar , AutoinformeRESUMEN
Background: Cost-effective demand-side interventions are needed to increase childhood immunization. Multiple studies find tying income support programs (≥USD 50 per year) to immunization raises coverage. Research on maximizing impact from small mobile-based conditional cash transfers (mCCTs) (≤USD 15 per fully immunized child) delivered in lower-income settings remains sparse. Methods: Participants in Karachi, Pakistan, were individually randomized into a seven arm, factorial open label study with five mCCT arms, one reminder (SMS) only arm, and one control arm. The mCCT arms varied by amount (high â¼USD 15 per fully immunized child versus low â¼USD 5 per fully immunized child), schedule (flat versus rising payments over the schedule), design (certain versus lottery payments), and payment method (airtime or mobile money). Children were enrolled at BCG, pentavalent-1 (penta-1) or pentavalent-2 (penta-2) vaccination and followed until at least 18 months of age. A serosurvey in 15% sub-sample validated reported study coverage. The full immunization coverage (FIC) at 12 months (primary outcome) was analyzed using logit regression. ClinicalTrials.gov (NCT03355989), 3ie registry (58f6ee7725fc1), and AEA RCT Registry (AEARCTR-0001953). Findings: Between November 6, 2017, and October 10, 2018, a total of 11,197 caregiver-child pairs were enrolled, with 1598-1600 caregiver-child pairs per arm. FIC at 12 months was statistically significantly higher for any mCCT versus SMS (OR:1.18, 95% CI: 1.05-1.33; p = 0.005). Within the mCCT arms, FIC was statistically significantly higher for high versus low amount (OR: 1.16, 95% CI: 1.04-1.29; p = 0.007), certain versus lottery payment (OR: 1.30, 95% CI: 1.17-1.45; p < 0.001) and airtime versus mobile money (OR: 1.17, 95% CI:1.01-1.36; p = 0.043). There was no statistically significant difference between a flat and increasing schedule (OR: 1.03, 95% CI: 0.93-1.15; p = 0.550). SMS had a marginally statistically significant impact on FIC versus control (OR: 1.16, 95% CI: 1.00-1.35; p = 0.046). Findings were similar for up-to-date coverage of penta-3, measles-1 and measles-2 at 18 months. Interpretation: Small mCCTs (USD 0.8-2.4 per immunization visit) can increase FIC at 12 months and up-to-date coverage at 18 months at USD 23 per additional fully immunized child, in resource-constrained settings like Pakistan. Design details (certainty, schedule and delivery method of mCCTs) matter as much as the size of payments. Funding: Global Innovation Fund, GiveWell.
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Vacunas contra la COVID-19 , COVID-19/prevención & control , Países en Desarrollo , Investigación Biomédica , COVID-19/economía , COVID-19/epidemiología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/provisión & distribución , Uso del Teléfono Celular , Control de Enfermedades Transmisibles , Humanos , India/epidemiología , Máscaras , Cobertura de Vacunación , Vacilación a la VacunaciónRESUMEN
During the Coronavirus Disease 2019 (COVID-19) epidemic, many health professionals used social media to promote preventative health behaviors. We conducted a randomized controlled trial of the effect of a Facebook advertising campaign consisting of short videos recorded by doctors and nurses to encourage users to stay at home for the Thanksgiving and Christmas holidays ( NCT04644328 and AEARCTR-0006821 ). We randomly assigned counties to high intensity (n = 410 (386) at Thanksgiving (Christmas)) or low intensity (n = 410 (381)). The intervention was delivered to a large fraction of Facebook subscribers in 75% and 25% of randomly assigned zip codes in high- and low-intensity counties, respectively. In total, 6,998 (6,716) zip codes were included, and 11,954,109 (23,302,290) users were reached at Thanksgiving (Christmas). The first two primary outcomes were holiday travel and fraction leaving home, both measured using mobile phone location data of Facebook users. Average distance traveled in high-intensity counties decreased by -0.993 percentage points (95% confidence interval (CI): -1.616, -0.371; P = 0.002) for the 3 days before each holiday compared to low-intensity counties. The fraction of people who left home on the holiday was not significantly affected (adjusted difference: 0.030; 95% CI: -0.361, 0.420; P = 0.881). The third primary outcome was COVID-19 infections recorded at the zip code level in the 2-week period starting 5 days after the holiday. Infections declined by 3.5% (adjusted 95% CI: -6.2%, -0.7%; P = 0.013) in intervention compared to control zip codes. Social media messages recorded by health professionals before the winter holidays in the United States led to a significant reduction in holiday travel and subsequent COVID-19 infections.
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Importance: Social distancing is critical to the control of COVID-19, which has disproportionately affected the Black community. Physician-delivered messages may increase adherence to these behaviors. Objectives: To determine whether messages delivered by physicians improve COVID-19 knowledge and preventive behaviors and to assess the differential effectiveness of messages tailored to the Black community. Design, Setting, and Participants: This randomized clinical trial of self-identified White and Black adults with less than a college education was conducted from August 7 to September 6, 2020. Of 44â¯743 volunteers screened, 30â¯174 were eligible, 5534 did not consent or failed attention checks, and 4163 left the survey before randomization. The final sample had 20â¯460 individuals (participation rate, 68%). Participants were randomly assigned to receive video messages on COVID-19 or other health topics. Interventions: Participants saw video messages delivered either by a Black or a White study physician. In the control groups, participants saw 3 placebo videos with generic health topics. In the treatment group, they saw 3 videos on COVID-19, recorded by several physicians of varied age, gender, and race. Video 1 discussed common symptoms. Video 2 highlighted case numbers; in one group, the unequal burden of the disease by race was discussed. Video 3 described US Centers for Disease Control and Prevention social distancing guidelines. Participants in both the control and intervention groups were also randomly assigned to see 1 of 2 American Medical Association statements, one on structural racism and the other on drug price transparency. Main Outcomes and Measures: Knowledge, beliefs, and practices related to COVID-19, demand for information, willingness to pay for masks, and self-reported behavior. Results: Overall, 18â¯223 participants (9168 Black; 9055 White) completed the survey (9980 [55.9%] women, mean [SD] age, 40.2 [17.8] years). Overall, 6303 Black participants (34.6%) and 7842 White participants (43.0%) were assigned to the intervention group, and 1576 Black participants (8.6%) and 1968 White participants (10.8%) were assigned to the control group. Compared with the control group, the intervention group had smaller gaps in COVID-19 knowledge (incidence rate ratio [IRR], 0.89 [95% CI, 0.87-0.91]) and greater demand for COVID-19 information (IRR, 1.05 [95% CI, 1.01-1.11]), willingness to pay for a mask (difference, $0.50 [95% CI, $0.15-$0.85]). Self-reported safety behavior improved, although the difference was not statistically significant (IRR, 0.96 [95% CI, 0.92-1.01]; P = .08). Effects did not differ by race (F = 0.0112; P > .99) or in different intervention groups (F = 0.324; P > .99). Conclusions and Relevance: In this study, a physician messaging campaign was effective in increasing COVID-19 knowledge, information-seeking, and self-reported protective behaviors among diverse groups. Studies implemented at scale are needed to confirm clinical importance. Trial Registration: ClinicalTrials.gov Identifier: NCT04502056.
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Negro o Afroamericano , COVID-19/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Promoción de la Salud , Médicos , Racismo , Población Blanca , Adulto , Comunicación , Competencia Cultural , Escolaridad , Femenino , Conductas Relacionadas con la Salud , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Distanciamiento Físico , Salud Pública , SARS-CoV-2 , Mercadeo Social , Encuestas y Cuestionarios , Adulto JovenRESUMEN
During the COVID-19 epidemic, many health professionals started using mass communication on social media to relay critical information and persuade individuals to adopt preventative health behaviors. Our group of clinicians and nurses developed and recorded short video messages to encourage viewers to stay home for the Thanksgiving and Christmas Holidays. We then conducted a two-stage clustered randomized controlled trial in 820 counties (covering 13 States) in the United States of a large-scale Facebook ad campaign disseminating these messages. In the first level of randomization, we randomly divided the counties into two groups: high intensity and low intensity. In the second level, we randomly assigned zip codes to either treatment or control such that 75% of zip codes in high intensity counties received the treatment, while 25% of zip codes in low intensity counties received the treatment. In each treated zip code, we sent the ad to as many Facebook subscribers as possible (11,954,109 users received at least one ad at Thanksgiving and 23,302,290 users received at least one ad at Christmas). The first primary outcome was aggregate holiday travel, measured using mobile phone location data, available at the county level: we find that average distance travelled in high-intensity counties decreased by -0.993 percentage points (95% CI -1.616, -0.371, p -value 0.002) the three days before each holiday. The second primary outcome was COVID-19 infection at the zip-code level: COVID-19 infections recorded in the two-week period starting five days post-holiday declined by 3.5 percent (adjusted 95% CI [-6.2 percent, -0.7 percent], p -value 0.013) in intervention zip codes compared to control zip codes. ONE SENTENCE SUMMARY: In a large scale clustered randomized controlled trial, short messages recorded by health professionals before the winter holidays in the United States and sent as ads to social media users led to a significant reduction in holiday travel, and to a decrease in subsequent COVID-19 infection at the population level.
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During the COVID-19 epidemic, many health professionals started using mass communication on social media to relay critical information and persuade individuals to adopt preventative health behaviors. Our group of clinicians and nurses developed and recorded short video messages to encourage viewers to stay home for the Thanksgiving and Christmas Holidays. We then conducted a two-stage clustered randomized controlled trial in 820 counties (covering 13 States) in the United States of a large-scale Facebook ad campaign disseminating these messages. In the first level of randomization, we randomly divided the counties into two groups: high intensity and low intensity. In the second level, we randomly assigned zip codes to either treatment or control such that 75% of zip codes in high intensity counties received the treatment, while 25% of zip codes in low intensity counties received the treatment. In each treated zip code, we sent the ad to as many Facebook subscribers as possible (11,954,109 users received at least one ad at Thanksgiving and 23,302,290 users received at least one ad at Christmas). The first primary outcome was aggregate holiday travel, measured using mobile phone location data, available at the county level: we find that average distance travelled in high-intensity counties decreased by -0.993 percentage points (95% CI -1.616, -0.371, p-value 0.002) the three days before each holiday. The second primary outcome was COVID-19 infection at the zip-code level: COVID-19 infections recorded in the two-week period starting five days post-holiday declined by 3.5 percent (adjusted 95% CI [-6.2 percent, -0.7 percent], p-value 0.013) in intervention zip codes compared to control zip codes.
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BACKGROUND: The paucity of public health messages that directly address communities of color might contribute to racial and ethnic disparities in knowledge and behavior related to coronavirus disease 2019 (COVID-19). OBJECTIVE: To determine whether physician-delivered prevention messages affect knowledge and information-seeking behavior of Black and Latinx individuals and whether this differs according to the race/ethnicity of the physician and tailored content. DESIGN: Randomized controlled trial. (Registration: ClinicalTrials.gov, NCT04371419; American Economic Association RCT Registry, AEARCTR-0005789). SETTING: United States, 13 May 2020 to 26 May 2020. PARTICIPANTS: 14 267 self-identified Black or Latinx adults recruited via Lucid survey platform. INTERVENTION: Participants viewed 3 video messages regarding COVID-19 that varied by physician race/ethnicity, acknowledgment of racism/inequality, and community perceptions of mask wearing. MEASUREMENTS: Knowledge gaps (number of errors on 7 facts on COVID-19 symptoms and prevention) and information-seeking behavior (number of web links demanded out of 10 proposed). RESULTS: 7174 Black (61.3%) and 4520 Latinx (38.7%) participants were included in the analysis. The intervention reduced the knowledge gap incidence from 0.085 to 0.065 (incidence rate ratio [IRR], 0.737 [95% CI, 0.600 to 0.874]) but did not significantly change information-seeking incidence. For Black participants, messages from race/ethnicity-concordant physicians increased information-seeking incidence from 0.329 (for discordant physicians) to 0.357 (IRR, 1.085 [CI, 1.026 to 1.145]). LIMITATIONS: Participants' behavior was not directly observed, outcomes were measured immediately postintervention in May 2020, and online recruitment may not be representative. CONCLUSION: Physician-delivered messages increased knowledge of COVID-19 symptoms and prevention methods for Black and Latinx respondents. The desire for additional information increased with race-concordant messages for Black but not Latinx respondents. Other tailoring of the content did not make a significant difference. PRIMARY FUNDING SOURCE: National Science Foundation; Massachusetts General Hospital; and National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases.
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Negro o Afroamericano , COVID-19/etnología , COVID-19/prevención & control , Información de Salud al Consumidor , Hispánicos o Latinos , Conducta en la Búsqueda de Información , Salud Pública/métodos , Adulto , COVID-19/epidemiología , Femenino , Humanos , Incidencia , Masculino , Máscaras , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/prevención & control , Neumonía Viral/virología , SARS-CoV-2 , Encuestas y Cuestionarios , Grabación en VideoRESUMEN
OBJECTIVE: Voluntary Counseling and Testing for HIV (VCT) and increasing access to male condoms are common strategies to respond to the HIV/AIDS pandemic. Using biological and behavioral outcomes, we compared programs to increase access to VCT, male condoms or both among youth in Western Kenya with the standard available HIV prevention services within this setting. DESIGN: A four arm, unblinded randomized controlled trial. METHODS: The sample includes 10,245 youth aged 17 to 24 randomly assigned to receive community-based VCT, 150 male condoms, both VCT and condoms, or neither program. All had access to standard HIV services available within their communities. Surveys and blood samples for HSV-2 testing were collected at baseline (2009-2010) and at follow up (2011-2013). VCT was offered to all participants at follow up. HSV-2 prevalence, the primary outcome, was assessed using weighted logistic regressions in an intention-to-treat analysis. RESULTS: For the 7,565 respondents surveyed at follow up, (effective tracking rate = 91%), the weighted HSV-2 prevalence was similar across groups (control group = 10.8%, condoms only group = 9.1%, VCT only group = 10.2%, VCT and condoms group = 11.5%). None of the interventions significantly reduced HSV-2 prevalence; the adjusted odds ratios were 0.87 (95% CI: 0.61-1.25) for condoms only, 0.94 (95% CI: 0.64-1.38) for VCT only, and 1.12 (95% CI: 0.79-1.58) for both interventions. The VCT intervention significantly increased HIV testing (adj OR: 3.54, 95% CI: 2.32-5.41 for VCT only, and adj OR: 5.52, 95% CI: 3.90-7.81 for condoms and VCT group). There were no statistically significant effects on risk of HIV, or on other behavioral or knowledge outcomes including self-reported pregnancy rates. CONCLUSION: This study suggests that systematic community-based VCT campaigns (in addition to VCT availability at local health clinics) and condom distribution are unlikely on their own to significantly reduce the prevalence of HSV-2 among youth.
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Condones , Consejo , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Adolescente , Cultura , Femenino , Estudios de Seguimiento , Infecciones por VIH/diagnóstico , Herpesvirus Humano 2/fisiología , Humanos , Análisis de Intención de Tratar , Kenia/epidemiología , Masculino , Población Rural , Adulto JovenRESUMEN
Randomized controlled trials have found only modest effects of microfinance, but these studies focus on new clients. Existing estimates may thus understate ongoing gains for more experienced borrowers and the longer-run potential of microfinance. We estimate impacts of microfinance on experienced borrowers, using an episode when a microfinance institution modestly increased existing clients' fees in randomly selected villages (in exchange for a mandatory health insurance policy that turned out to be useless). This increase in fees led to a 22 percentage point decline in loan renewal in treatment villages (95% confidence interval: 16 to 27), compared to control villages where the policy was not introduced. Using this randomly generated variation in microfinance participation among experienced borrowers, we find impacts of microfinance that are strikingly similar to previous estimates for new clients: neither business outcomes nor household consumption were affected, on average. Also, consistent with prior studies, we find significant impacts on business outcomes among clients who had started their businesses before microfinance entered the village (0.06 standard deviation decline in an index of business outcomes from the loss of microfinance, 95% confidence interval: -0.002 to -0.12). However, despite these measured losses, these clients were just as willing to give up microfinance.
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INTRODUCTION: Prenatal care is recommended during pregnancy to improve neonatal and maternal outcomes. Women of lower socioeconomic status (SES) are less compliant to recommended prenatal care and suffer a higher risk of adverse perinatal outcomes. Several attempts to encourage optimal pregnancy follow-up have shown controversial results, particularly in high-income countries. Few studies have assessed financial incentives to encourage prenatal care, and none reported materno-fetal events as the primary outcome. Our study aims to determine whether financial incentives could improve pregnancy outcomes in women with low SES in a high-income country. METHODS AND ANALYSIS: This pragmatic cluster-randomised clinical trial includes pregnant women with the following criteria: (1) age above 18 years, (2) first pregnancy visit before 26 weeks of gestation and (3) belonging to a socioeconomically disadvantaged group. The intervention consists in offering financial incentives conditional on attending scheduled pregnancy follow-up consultations. Clusters are 2-month periods with random turnover across centres. A composite outcome of maternal and neonatal morbidity and mortality is the primary endpoint. Secondary endpoints include maternal or neonatal outcomes assessed separately, qualitative assessment of the perception of the intervention and cost-effectiveness analysis for which children will be followed to the end of their first year through the French health insurance database. The study started in June 2016, and based on an expected decrease in the primary endpoint from 18% to 14% in the intervention group, we plan to include 2000 women in each group. ETHICS AND DISSEMINATION: Ethics approval was first gained on 28 September 2014. An independent data security and monitoring committee has been established. Results of the main trial and each of the secondary analyses will be submitted for publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT02402855; pre-results.
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Motivación , Aceptación de la Atención de Salud , Complicaciones del Embarazo/prevención & control , Resultado del Embarazo , Atención Prenatal/economía , Clase Social , Adulto , Femenino , Feto , Francia , Edad Gestacional , Humanos , Salud del Lactante/economía , Recién Nacido , Salud Materna/economía , Embarazo , Complicaciones del Embarazo/economía , Derivación y Consulta , Proyectos de Investigación , Poblaciones Vulnerables , Adulto JovenRESUMEN
Many poor children are underprepared for demanding primary school curricula. Research in cognitive science suggests that school achievement could be improved by preschool pedagogy in which numerate adults engage children's spontaneous, nonsymbolic mathematical concepts. To test this suggestion, we designed and evaluated a game-based preschool curriculum intended to exercise children's emerging skills in number and geometry. In a randomized field experiment with 1540 children (average age 4.9 years) in 214 Indian preschools, 4 months of math game play yielded marked and enduring improvement on the exercised intuitive abilities, relative to no-treatment and active control conditions. Math-trained children also showed immediate gains on symbolic mathematical skills but displayed no advantage in subsequent learning of the language and concepts of school mathematics.
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Intervención Educativa Precoz/métodos , Intuición , Conceptos Matemáticos , Matemática , Niño , Preescolar , Ciencia Cognitiva , Femenino , Humanos , India , Lenguaje , Aprendizaje , Masculino , Pobreza , Distribución Aleatoria , Instituciones AcadémicasRESUMEN
A seven-year randomized evaluation suggests education subsidies reduce adolescent girls' dropout, pregnancy, and marriage but not sexually transmitted infection (STI). The government's HIV curriculum, which stresses abstinence until marriage, does not reduce pregnancy or STI. Both programs combined reduce STI more, but cut dropout and pregnancy less, than education subsidies alone. These results are inconsistent with a model of schooling and sexual behavior in which both pregnancy and STI are determined by one factor (unprotected sex), but consistent with a two-factor model in which choices between committed and casual relationships also affect these outcomes.
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Educación/economía , Infecciones por VIH/prevención & control , Estado Civil , Embarazo en Adolescencia , Evaluación de Programas y Proyectos de Salud , Educación Sexual/economía , Conducta Sexual , Enfermedades de Transmisión Sexual/prevención & control , Adolescente , Vestuario/economía , Condones/estadística & datos numéricos , Escolaridad , Relaciones Extramatrimoniales , Femenino , Fertilidad , Herpes Genital/prevención & control , Humanos , Kenia , Masculino , Embarazo , Abstinencia Sexual , Parejas Sexuales , Enfermedades de Transmisión Sexual/epidemiología , Sexo Inseguro , Adulto JovenRESUMEN
We present results from six randomized control trials of an integrated approach to improve livelihoods among the very poor. The approach combines the transfer of a productive asset with consumption support, training, and coaching plus savings encouragement and health education and/or services. Results from the implementation of the same basic program, adapted to a wide variety of geographic and institutional contexts and with multiple implementing partners, show statistically significant cost-effective impacts on consumption (fueled mostly by increases in self-employment income) and psychosocial status of the targeted households. The impact on the poor households lasted at least a year after all implementation ended. It is possible to make sustainable improvements in the economic status of the poor with a relatively short-term intervention.
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To study the impact of the choice of injection points in the diffusion of a new product in a society, we developed a model of word-of-mouth diffusion and then applied it to data on social networks and participation in a newly available microfinance loan program in 43 Indian villages. Our model allows us to distinguish information passing among neighbors from direct influence of neighbors' participation decisions, as well as information passing by participants versus nonparticipants. The model estimates suggest that participants are seven times as likely to pass information compared to informed nonparticipants, but information passed by nonparticipants still accounts for roughly one-third of eventual participation. An informed household is not more likely to participate if its informed friends participate. We then propose two new measures of how effective a given household would be as an injection point. We show that the centrality of the injection points according to these measures constitutes a strong and significant predictor of eventual village-level participation.