Messages on COVID-19 Prevention in India Increased Symptoms Reporting and Adherence to Preventative Behaviors Among 25 Million Recipients with Similar Effects on Non-recipient Members of Their Communities

"[E]ven against a background of a high level of messaging, an additional message by a respected public figure can still have large direct and indirect effects."

Very quickly after the onset of the COVID-19 pandemic, people were inundated with messages from numerous sources. In India, by the end of March and beginning of April 2020, individuals received official messages about physical distancing and hygiene through television, radio, public signs, local government addresses, and a short jingle accompanying outgoing mobile phone calls. Evidence suggests that the Indian government's public health messaging was in large part either ignored, forgotten, misunderstood, or insufficiently disseminated within the community. In this context, among the questions this evaluation sought to answer were: How can we create messages to have an impact in this setting of information overload? Does additional "light-touch messaging" by a credible, well-known individual change behaviour? Do the features of the message matter? Is it important that we reach everyone directly, or can we limit outreach and rely on the information diffusing through the community?

To explore these questions, the researchers conducted a large-scale messaging campaign in West Bengal, a large state in India with a population of 91.3 million, over two-thirds of whom live in rural areas. As control, 3 million subscribers of the phone network Reliance Jio (henceforth Jio) received a short messaging service (SMS, or text) containing a link to the government website on COVID-19, similar to the many messages they have already received. On the other hand, 25 million Jio users were sent a text containing a link to a 2.5-minute YouTube (video) clip delivered by one of the researchers, West Bengal native and 2019 Nobel laureate Abhijit Banerjee, who is also the chair of the West Bengal COVID-19 advisory board. His accomplishments and work have been covered extensively by the media in West Bengal.

All video messages instructed individuals with cough and fever to contact their local community health workers (Accredited Social Health Activists, known as ASHAs). In addition, there were 8 different variants emphasising one practice (social distancing or hand-washing), one rationale for action (cost to self or cost to everyone, including self), and a social problem (either an explicit statement that ostracism of COVID-19 victims is unacceptable and should be reported to the authorities, or no mention of the issue). Experimental message treatments were randomised at the PIN (Postal Index Number) code level.

A few days after the campaign, the researchers conducted 2 phone surveys. First, they surveyed 677 ASHAs from the sample communities to ask them about reporting of symptoms. Second, they surveyed a random sample of 1,883 individuals drawn from a publicly available database of former and current local village council (gram panchayat) members to ask them questions about the message they had received (Jio users) and their knowledge of COVID-19; those who were not messaged directly (non-Jio users) were also included in this survey.

The campaign was found to have:

• Doubled the reporting of health symptoms to the ASHAs (p = 0.001 for fever, p = 0.024 for respiratory symptoms), which almost certainly reflects reporting rather than an increased level of sickness, given lag times for transmission and the time it takes for someone to become symptomatic.
• Decreased travel beyond one's village in the previous 2 days by 20% (p = 0.026) (on a basis of 37% in control) and increased estimated hand-washing when returning home by 7% (p = 0.044) (on a basis of 67.5% in control).
• Spilled over to behaviours not mentioned in the message: Mask-wearing was never mentioned but increased 2% (p = 0.042), while distancing and hygiene both increased in the sample where they were not mentioned by similar amounts as where they were mentioned.
• Spilled over onto nonrecipients within the same community, with effects similar to those for individuals who received the messages. Based on questions included in the survey, it does not appear likely that it is through conversations about COVID-19 that the intervention led to such large-scale community diffusion; it seems more likely to have come from direct observations and imitation of behaviour.

Given the large reach of the messaging campaign, 279,800 unique individuals eventually clicked on the link to watch the video. However, the share of videos watched on average was only 1.14%, which is consistent with the literature on click-through-rates. The rate of viewing did not vary by message content. Combined with the effect on non-targeted behaviour and non-targeted community members, this finding suggests that the video had indirect impacts on many who did not watch.

The results point to several policy implications:

1. There is value in persistent messaging, at least by celebrities. Though there is a lot of information being transmitted in a pandemic environment, a new message can act as a nudge and reminder; this may be particularly important if the conditions change and updating the information is necessary.
2. The exact content of the message may not matter, since the information is out there, and what is needed is a nudge to pay attention to it. Indeed, the literature finds that very long messages impede comprehension, so the message should be short rather than comprehensive.
3. Behaviour and knowledge are not one-to-one. The researchers observed large shifts in distancing, hygiene, and mask-wearing, despite little to no shifts in knowledge. Emphasis on behaviour seems to be paramount.
4. Given that governments have a fixed budget for messages, and since within-community spillovers are large, it is important to disseminate the messages broadly across many communities, rather than using the same budget to try to reach more people within a particular community.

In sum, the results suggest an important role for messaging by credible individuals.