Rebecca ThorntonUniversity of Michigan and J-PAL

Medical trials◦ Treatment of STIs (Rakai, Mwanza, Masaka, Manicaland)◦ Vaccines◦ Microbicides

Behavioral trials◦ Education

Individual training (Awareness and strategies); (Duflo et al. 2007) Teacher training (Duflo et al. 2007) Risk knowledge (Dupas 2007) Staying in school (incentives); (Ozler et al.) Costs of school (Uniforms); (Duflo et al. 2007)

◦ Knowledge of HIV status◦ Financial incentives

Thornton, Rebecca The Demand for and Impact of Learning HIV Results. Evidence from a Field Experiment, 2008

Once people learn their HIV status, they will engage in safer sexual behavior

What is the impact of learning HIV results? Limitations with existing studies

◦ Self-reported behavior◦ Selection

Who chooses to test or learn results Where testing centers are located

Field experiment in rural Malawi

MDICP (1998, 2001, 2004) ◦ 125 rural villages in three locations◦ Randomly selected HH; Men, women and adolescents

2004: Offered free HIV and STI tests 91% accepted (2,894)

Randomly assigned voucher to learn HIV results◦ Between $0-$3.00 (average=$1.04)◦ 20% received no incentive◦ Smallest amount: $0.10

Results centers◦ Randomly placed based on HH GPS and clustered by

village◦ Average distance = 2 km

Follow-up survey (2 districts)◦ Reported purchases of condoms (8%)◦ Sexual activity since VCT (62%)◦ Actual purchases of condoms

Gave $0.30; sold condoms at half (subsidized) retail price

24% purchased condoms; 3.7 condoms on average

Note◦ No differential attrition (incentives or distance)◦ Balanced on observables◦ Distinguish between sexually active and not

• HIV Negatives who had sex at Baseline

• HIV Positives who had sex at Baseline

• After 2 years (2006) – re-survey respondents• No differential attrition• Preliminary results (Kohler and Thornton)

HIV positive in 2006

Any sex in past year

Purchased condoms

(2 months) Condoms at home

(1) (2) (3) (4)

Got HIV neg results (2004) 0.012 -0.022 0.049 0.074**

[0.014] [0.387] [0.044] [0.037]

Observations 1765 1629 1883 1884 R-squared 0.00 0.15 0.07 0.03

Barriers to learning HIV results can be easily overcome

After 2 months: little change in demand for condoms◦ Large increase in the likelihood of purchasing condoms

(HIV+ with a partner)◦ However, number of condoms purchased small

After 2 years: no difference in HIV status; little change in reported sexual behavior

What are an individual’s incentives to change behavior?

Standard economic theory◦ Benefits vs. costs of an act of unsafe sex

Behavioral economics◦ Hyperbolic discounting◦ Difficulty delaying gratification (abstaining, using a

condom)◦ Salience of HIV infection at the time of sexual act

Can conditional financial incentives affect sexual behavior?

MDICP subsample in rural Malawi (Kohler and Thornton) Survey and HIV testing: June – August 2006

◦ 28% tested as a couple; 72% as an individual◦ Oversample discordant couples: 9.1 HIV positive

Incentives to “maintain” HIV status: August 2006◦ Couples: If no longer with spouse or refuse a couple test,

automatically enrolled into individual program

Collect sexual diaries throughout the year Test for HIV and give out financial incentives

Couple Individual

None 0 0

Medium 1000 500

High 4000 2000

Difference between those who were offered incentives and those who were not

Preliminary results Possible considerations:

◦ Not measuring sexual behavior in the right way◦ Not the right population◦ Not enough money◦ Incentive too far out in the future

Another incentives project (Dewalque et al.)◦ STIs◦ Quarterly incentives

What worked: ◦ Reducing the costs to education◦ Small short-run incentives to learn HIV results

What didn’t work:◦ Learning about HIV status◦ Moderate incentives for maintaining HIV status

Increase incentive? Decrease time to earn incentive?

What other prevention strategies could have important large effects?

HIV is tricky to study◦ Lots of endogeneity◦ Measurement of variables