Effect of Tailored Information of Vaccination Schedule on Vaccine Uptake in Northern Nigeria

"A vaccination schedule is complex and dynamic that requires repetitive and timely clinic visits by children and their caretakers."

African countries suffer not only from low vaccination coverage but also from high dropout rate and delayed vaccination uptake. Caregivers' documented misconception of "complete vaccination" can be attributed to the complicated vaccination schedule in Nigeria, for example. There, to cite one vaccination only, children are scheduled to receive the oral poliovirus vaccine (OPV) four times, but then the new vaccine, inactivated polio vaccine (IPV), was introduced in 2015 in Nigeria; it is to be received at 14 weeks after birth. Among the various potential barriers to vaccination, this study focused on the lack of information on the vaccination schedule and investigated whether providing caregivers one-time tailored information on the vaccination schedule improves the vaccine uptake among children.

The study participants were 534 women, each with a child under 8 months of age; they were from 11 settlements in Jada, a local government area in Adamawa state, Nigeria. The study was conducted on September 2019 to June 2020. The researchers employed the ordinary least squares and logistic regression, depending on the type of dependent variables, to analyse the treatment effect.

The intervention, which took place at the respondents' households, began with respondents picking paper strips from a bag to determine which group they would be in (randomisation). Trained interviewers first examined the vaccination cards of the children of women in the treatment arm. If they identified any missed vaccinations in the vaccination cards, they informed the women and told them the type of vaccinations that were missed. Then, they encouraged the women to bring their children to the health facility as soon as possible to receive the vaccines they had missed. If the children of the women in the treatment arm did not miss any vaccination, they were informed about the next vaccination date. Interviewers wrote down the next vaccination date in the vaccination card and gave it to the women. On the other hand, women in the control arm were provided general information on the vaccination schedule verbally regardless of the children's vaccination status. They were not given tailored information, such as whether their children missed any vaccination in the past and when the next vaccination was scheduled.

The treatment increased the odds of visiting the health centre for vaccination at least once by 1.5. On the other hand, the treatment did not improve the vaccination rate at any given time; nor did it increase the full vaccination rate. "This result implies that one-time tailored information has only an immediate but no sustainable effect. However, because one-time information provision can influence the immediate vaccination behaviour, it might be important to constantly remind women about the vaccination schedule in a timely manner, particularly right before when caregivers are expected to take their children to the health facility for vaccination."

In conclusion: "One-time tailored information on the vaccination schedule increases women's clinic visits for the vaccination of their children, but it is not sufficient to improve the full vaccination rate."