Small financial incentives, of as little as £30, could encourage injecting drug users to complete a course of hepatitis B virus (HBV) vaccination, according to researchers.
A new study published in The Lancet found heroin users who received a maximum total of £30 supermarket vouchers in equal or graduated instalments in return for full compliance with a regimen of three HBV vaccine injections were at least 12 times as likely to complete the course within 28 days, compared with those not receiving a financial incentive.
“The size of the increase we observed was striking”
The study was led by Professor John Strang from the National Addiction Centre at King’s College London, which also included researchers at Imperial College London and University College London.
“That monetary incentives increase compliance is unremarkable, but the size of the increase we observed was striking,” said Professor Strang.
“Injecting drug users are at high risk of infection and transmission of hepatitis B. This is a potentially life-saving vaccine, and increasing its uptake among this group has important benefits to public health, as well as to the individual.”
HBV affects about 22% of injecting drug users in the UK. Medication can slow the spread of the virus, although there is no completely effective cure.
It is estimated that 15%-25% of people with untreated chronic HBV die of liver disease. A highly effective vaccine exists, but the rate of vaccination uptake is poor.
The researchers randomly assigned 210 patients into three groups: HBV vaccination without incentive, fixed value contingency management (£10 voucher at each of three vaccinations), or escalating value contingency management (£5 voucher at first vaccination visit, £10 voucher at second visit, and £15 voucher at third visit).
Only 9% of 67 participants in the treatment as usual group completed all scheduled vaccinations, compared with 45% of 78 participants in the fixed reward group, and 49% of 65 participants in the escalating reward group.
Some 80% of participants receiving financial incentives also attended appointments on time, ensuring a more efficient use of resources.
- Read the full study paper in The Lancet