Tailored online interventions to promote seasonal influenza vaccination

In a recent study published in JAMA Network Open, researchers evaluated the efficacy of tailored online interventions in improving seasonal influenza vaccination (SIV) uptake among older adults.

Study: Chatbot-Delivered Online Intervention to Promote Seasonal Influenza Vaccination During the COVID-19 Pandemic. Image Credit: BaLL LunLa/Shutterstock.com

Background

SIV can effectively prevent influenza and mortality among older adults. The Center for Health Protection in Hong Kong recommends that adults aged 65 or older receive SIV yearly.

Although SIV is free for this age group in Hong Kong, its coverage is inadequate and was 40.4% in 2021-22. Fewer trials have compared the efficacy of mailing reminders to no intervention but had small effect sizes.

Although home visits and telephone sessions appear effective and have larger effect sizes, they are more resource-intensive.

One study observed that standard verbal education by medical students was effective in increasing SIV uptake. Nevertheless, tailored interventions for SIV are lacking among older adults.

A stage of change (SOC) measures readiness for behavioral change. A meta-analysis revealed higher efficacy of SOC-tailored interventions, especially in less motivated subjects, than interventions not tailored to SOCs. Chatbots can be potentially valuable in delivering SOC-tailored interventions promoting SIV.

About the study

In the present study, researchers assessed the efficacy of chatbot-delivered SOC-tailored interventions in improving SIV uptake among older adults in Hong Kong. This non-blinded randomized controlled trial (RCT) was performed between December 2021 and July 2022.

Eligible subjects were community-dwelling, Cantonese- or Mandarin-speaking smartphone users aged 65 or older who did not take SIV during the 2021-22 influenza season.

Individuals with contraindications to SIV, cognitive impairment, deafness, blindness, or the inability to communicate were excluded. Random telephone sampling was implemented for recruitment. Participants were offered supermarket coupons after the baseline survey and six months post-intervention.

Subjects were randomized to the intervention or control arm after the baseline survey. Intervention participants watched one of the SOC-tailored health promotional videos on SIV uptake every two weeks for four sessions. The messages in the videos followed strategies to facilitate SOC progression. Four videos with slight variations were prepared to prevent repetition.

Participants' SOC was assessed based on their intention to receive SIV. SOCs included pre-contemplation, contemplation, and preparation stages. The pre-contemplation stage was defined as having no intention to take SIV in the next six months.

The contemplation stage was the intention to receive SIV in the next six months without plans to take SIV in the next month. The preparation stage was the intention to take SIV in the next month.

Beginning the second session, subjects were asked if they had already been vaccinated for the upcoming influenza season, and positive responders were deemed to be at the action stage. Similarly, controls received standard videos at the same intervals. Information in these videos was identical to that disseminated by the government through mass media. The study's outcomes included SIV uptake at six months and SOC at baseline and six months.

Findings

Overall, 396 participants completed the baseline survey; they were aged, on average, 70.2. Most subjects (62.9%) were females. Approximately 60% of participants had ever been vaccinated for influenza.

About 37.4%, 22%, and 40.6% of participants were at the pre-contemplation, contemplation, and preparation stages, respectively. At six months, 100 and 70 participants in the intervention and control groups were at the action stage.

The SIV uptake rate and the average SOC score were significantly higher among intervention subjects than controls.

Among the 117 intervention participants completing at least two sessions, 55.6% progressed to a higher SOC, with a statistically significant increase in their mean SOC score from the first to the (most) recent session.

More intervention participants completed at least one session than controls, and many in the intervention group (80%) were satisfied with the promotional messages in the videos.

Conclusions

The study revealed a higher efficacy of SOC-tailored intervention in improving SIV uptake than the standard, non-SOC-tailored intervention, with about ten percentage points higher SIV uptake rate in the intervention group than the overall SIV coverage among older adults in Hong Kong.

The intervention system was viable to provide tailored health promotional messages according to participants' SOC and required fewer resources, given that it can automatically evaluate SOC and select appropriate interventions.

Overall, the findings suggest that SOC-tailored interventions may be (more) sustainable in increasing SIV uptake.

Written by

Tarun Sai Lomte

Tarun is a writer based in Hyderabad, India. He has a Master’s degree in Biotechnology from the University of Hyderabad and is enthusiastic about scientific research. He enjoys reading research papers and literature reviews and is passionate about writing.