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Health worker absence, HIV testing and behavioral change. Markus Goldstein (World Bank) Joshua Graff Zivin (UCSD) James Habyarimana (Georgetown) Kiki Pop-Eleches (Columbia) Harsha Thirumurthy (UNC-Chapel Hill). Information and behavior. Information assumed to shape choices and behavior
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Health worker absence, HIV testing and behavioral change Markus Goldstein (World Bank) Joshua Graff Zivin (UCSD) James Habyarimana (Georgetown) Kiki Pop-Eleches (Columbia) Harsha Thirumurthy (UNC-Chapel Hill)
Information and behavior • Information assumed to shape choices and behavior • This has implications for effects of HIV testing • Provides information about future health and longevity • Setting for this study • Antenatal clinic in Kenya where testing is offered to pregnant women for prevention of MTCT • Aim: study take-up of HIV testing and impact of learning HIV status on behavioral outcomes
Two important aspects of HIV testing • Take-up of HIV testing • Supply and demand side factors influence this, but role of each not well understood • Should testing be an important component of policy response to HIV? • Discussion has largely focused on its impact on sexual behavior (Coates et al. 2000; Thornton 2008) • Impacts on other outcomes largely neglected • Take-up of other valuable health services • forward-looking behavior
Obstacles to scale-up of HIV testing • Supply and demand side factors • Demand side factors (see Thornton 2008 & others) • This paper focuses on supply side • Structural constraints (health worker absence) • Health worker absence in developing world • 35% absence rate among public health providers (Chaudhury et al. 2005) • Limited evidence re: impact on health outcomes • Also a valid instrument for testing decision
Effects of HIV testing (1): health outcomes • Main reason for testing pregnant women: provide PMTCT medication & advice • In 2005, 11% of HIV+ women in Africa got PMTCT • Inexpensive & effective meds available for PMTCT • Nevirapine ($0.50 per dose) • In this setting, ARV therapy also given for PMTCT • Other possible benefits of PMTCT counseling • Healthier mothers and children through safer delivery and increased take-up of neonatal care
Effects of HIV testing (2): socio-economic behavior • Information about future health & expected longevity should affect number of inter-temporal investment decisions at household level • Fertility – important assumption in macro models of impact of AIDS epidemic (Young 2005) • Human capital formation • Asset accumulation
TESTING AND COUNSELLING: HEALTH OUTCOMES BREAST FEED Individual ANC HEALTH OUTCOMES BIRTH LOCATION TEST Structural Inputs PMTCT
TESTING AND COUNSELLING: ECONOMIC OUTCOMES FERTILITY Individual ANC ECONOMIC OUTCOMES TEST SCHOOLING Structural Inputs INVESTMENT
Summary of results Absence rate of 10% of PMTCT nurse Large effect on uptake of testing and counseling Large effect on delivery of PMTCT medications Safer delivery Lower likelihood of breastfeeding Change in investment behavior among negatives Asset accumulation Schooling No effects on fertility preferences
Outline • Panel survey of pregnant women in Kenya • HIV testing decisions and nurse absence
Survey in Nyanza Province Kenya adult prevalence 6.7% (1.2 million) Nyanza Province adult prevalence of 20% Rural health center provides ANC care, and has HIV clinic that provides ARVs (managed by AMPATH program) Survey conducted in two waves
Panel survey of pregnant women • Wave 1: In-clinic interview before HIV test (July ‘05 – Feb ‘06) • Only first time visitors for current pregnancy interviewed • Short questionnaire, included subjective beliefs about HIV status • 650 women from catchment area enrolled • HIV testing offered after wave 1 interview • Wave 2: Household interview (May ‘06 – Feb ‘07) • comprehensive socio-economic data collected at home: • demographics, education, health, employment, sexual behavior, assets, etc • Interviewed ANC client and spouse • Completed panel on 591 women (9% attrition) • Loss to follow up generally due to relocation out of province
Additional data obtained from clinic • PMTCT logbook • HIV status: continuously updated because pregnant women could have tested on subsequent antenatal visits • Nurse presence/absence: based on # of women tested • AMPATH records • Fraction of HIV+ women who enrolled (imperfect matching)
PMTCT in western Kenya • Pregnant women typically get tested at first ANC visit • 3 visits recommended • Most common med for HIV+ women: Nevirapine • Given to the mother with onset of labor and drops given to the baby within 72 hours of birth • Reduces the risk of transmission by about 50% • In our study setting, ART also given for PMTCT • Breastfeeding generally not recommended
Health worker absence & HIV testing • About 77% of women in panel data tested for HIV • 25% of those who tested were HIV+ • Controlling for selection into testing • 10% absence rate for PMTCT nurse (relatively small) • Useful as an instrumental variable to deal with selection • Effect of absence on testing is first stage • Also control for day of the week and prior beliefs
HIV testing and behavior change • Instrument for testing offers opportunity to examine whether behavior changes after learning HIV status • We estimate separate effects for HIV- and HIV+ women • Comparison group? • We compare to women who do not get tested but have similar pre-test beliefs about own status
IV strategy for estimating impact of testing (by test result) • Ideally: • Do not know status for non-testers • Therefore, we assume that • Control for pre-test subjective beliefs • Our assumption (non-testers’ behavior shaped by beliefs)
Subjective beliefs about HIV status • First, are pre-test subjective beliefs good proxy for HIV status? • i.e. do pre-test beliefs predict actual test result? • Second, do beliefs change after learning HIV status? • Perhaps a prerequisite for behavioral change to occur • We examine beliefs about own status and partner’s status
HIV testing and behavior change • Evidence of changes in subjective beliefs about one’s status provide motivation for other behavioral responses • We first estimate average effect across all women who learn they are HIV+ and HIV- (not interacted with pre-test beliefs)
Why pre-test beliefs may matter (Boozer & Philipson 2000) Costs and Benefits of testing Benefit of testing Cost of testing High-risk Prior belief (subj. belief) Low-risk
Literature has focused largely on the effect of HIV testing on sexual behavior • Policy rationale • Those who test HIV- may have incentives to avoid infection • Those who test HIV+ can be encouraged to adopt safe sex practices • Effects are theoretically ambiguous • In both cases, the opposite response possible • Existing studies of testing and sexual behavior • Coates el al. 2000: VCT, Kenya and Tanzania • Thornton 2005: community-based VCT, Malawi
Impacts on other outcomes also important for evaluation of HIV testing • PMTCT take-up, health outcomes • Socio-economic behavior, particularly forward-looking decisions
Heterogeneous response by level of surprise and updating • As in Boozer and Philipson (JHR 2000) • Do women who learn more from the HIV test have larger changes in behavior? • Not much evidence that this matters • Actual test result is more salient than how surprised one is by the test result
Summary of results • Absence rates are moderate but have large effects on PMTCT outcomes • Pre-test beliefs do predict HIV status, and these beliefs evolve over time • Increases in investment behavior for women who test HIV-negative • No effect on fertility