Impact of a vaccination promotion intervention using motivational interview techniques on long-term vaccine coverage: the PromoVac strategy

ABSTRACT

Background: Delayed vaccinations at 2, 4, and 6 months are associated with a higher probability of delayed age-appropriate vaccination during childhood. This study aimed to assess the effectiveness of an information session on immunization during infancy.

Methods: An individual educational information session with motivational interview techniques for immunization of infants was conducted (experimental group) or not conducted (control group) during postpartum stay in a quasi-experimental cohort study. Immunization data were collected from the Eastern Townships Public Health registry at 3, 5, 7, 13, 19, and 24 months of age. Logistic regressions with repeated measures were performed to assess the intervention’s impact. Relative risks (RR) were estimated. A multivariate model was obtained adjusted for confounding factors.

Results: The experimental and control groups included 1140 and 1249 families, respectively. In per protocol analysis, a significant increase in VC of 3.2, 4.9, 7.3, 6.7, 10.6, and 5.1% was observed at 3, 5, 7, 13, 19, and 24 months. Children from experimental group had 9% more chance at a complete vaccination status between 3 and 24 months compared to children from control group (RR (95% CI): 1.09 (1.05-1.13), p < .001). Children with complete vaccination status at 3 months were more likely to have a complete vaccination status at 24 months (82.3 vs. 48.1%, RR (95% CI): 2.72 (2.28-3.24), p < .001). After adjustment, the estimated RR of the intervention’s impact was 1.05 (1.02-1.07), p < .001.

Conclusions: An educational information session about immunization based on motivational interview techniques conducted during postpartum hospitalization could improve immunization during infancy.

KEYWORDS:

• Motivational interviewing
• vaccine coverage
• infants
• health promotion intervention
• maternity wards

Abbreviations

CHUS	=	Centre hospitalier universitaire de Sherbrooke
CI	=	confidence intervals
GEE	=	generalized estimating equations
ITT	=	intention-to-treat
MI	=	motivational interview
PP	=	per-protocol
RR	=	relative risk
VC	=	vaccine coverage

Disclosure of potential conflicts of interest

No potential conflict of interest were disclosed.

Acknowledgments

The authors would like to thank all mothers who took part in this study during their post-partum stay. Then, we would like to thank all the nurses as well as health professionals of the CHUS maternity ward. We also would like to thank Pierrot Richard and Arianne Grégoire from the Eastern Townships public health department for their precious assistance in the collect of vaccination data.

Contributor’s Statements

Thomas Lemaitre acquired, analyzed and interpreted the data, drafted the article, and approved the final version of the manuscript to be submitted.

Nathalie Carrier performed data analysis and data interpretation, and reviewed and edited the final manuscript.

Anne Farrands participated in the mothers’ recruitment, performed MI sessions, collected data, and reviewed and edited the final manuscript.

Virginie Gosselin performed data interpretation, and reviewed and edited the final manuscript.

Geneviève Petit participated in the conception and design of the study, performed data interpretation, and reviewed and edited the final manuscript.

Arnaud Gagneur developed the strategy, designed the study, performed data analysis and data interpretation, wrote, reviewed and edited the final manuscript.

Additional information

Funding

This study was funded with the public health subsidy program of the Eastern Townships public health department. The authors have no financial relationships relevant to this article to disclose.