Why voice notes have better outcomes than texts

We used to talk to people face to face. Then the telephone was invented, and we could talk to people in different towns, even different countries. Enter the digital era, ushering in a host of new ways to communicate, both in work settings and our personal lives.

Some digital innovations were clunky and short-lived, but others have endured and thrived: emails, video calls, texts, chats, and voice messages. And it’s the latter that particularly interests Xu Zhang, Assistant Professor of Marketing at LBS.

Imagine if you could message your doctor as easily as you message a friend. That’s already the reality for patients in China, where digital apps such as WeChat or Alipay have become a common gateway to healthcare services, changing how many people book, manage and even undergo medical appointments.

Healthcare at scale

Finding ways to provide healthcare at scale to a shifting demographic is a massive global headache. By 2050, 22% of people will be over 60 (up from 12% in 2015). While longer lifespans present huge opportunities for individuals and societies, it’s an inescapable fact that increasingly ageing populations also require more medical support. Healthcare systems all around the world are under immense strain.

One place where digital tools are already delivering care at scale is China. In 2019 the country had fewer than 300 licensed internet hospitals. Today it has more than 3,000. China has the world’s largest number of online medical consultation users, more than 30% of the global total – with transactions exceeding US$ 1.4 billion in 2025.

WeChat, one of the biggest players in this space, has morphed into an all-in-one digital super-app, with more than 1.4 billion monthly active users. Users open ‘Mini-Programs’ (apps within the app) run by hospitals and healthcare platforms, where they can choose a hospital or doctor and book a time slot.

But it doesn’t stop there. The tech supports the patient through the entire journey – including payments. If a doctor orders a blood test or an X-ray, the patient can pay for it in the app. Likewise, test results and digital prescriptions are delivered within the same app.

Various researchers have investigated medical chatbot interactions. But Zhang and her co-author Yi Zhang, a postdoctoral researcher at The Hong Kong Polytechnic University, wanted to look at how human doctors communicate with their patients and, specifically, what difference it makes when they send voice notes as part of the back-and-forth messaging.

Can voice notes improve outcomes?

Previous studies suggested that text-based formats are often more structured and thoughtful. Text can also be easier for recipients to scan, reread and annotate, making it well-suited for information that requires reflection or later reference.

In contrast, voice notes can be more expressive and are quicker for senders to produce, but they are harder for recipients to retain and revisit.

The researchers analysed a unique dataset of more than 1.8 million real online doctor–patient consultations from one of China’s leading dedicated telehealth platforms, where patients can consult physicians directly by chat. The physicians were distributed across 30 provinces in mainland China. The consultations cost on average 124 RMB (US$ 17).

For each consultation, they looked at patient, physician and consultation characteristics. For example, they counted the number of anxiety-related words within the intake forms patients filled in before the consultation, and recorded patient history such as prior consultations, chronic conditions and hospital visits.

Xu Zhang and Zhang studied the full sequence, content, and modality of exchanged messages. They even accounted for the doctor’s time pressure, impatience and fatigue on that day by measuring aspects of their workload.

To measure how patients responded, the researchers looked at four outcomes: whether patients thanked their doctor, sent a gift, said they would follow the doctor's advice, or would come back for another consultation.

Double machine learning was used to separate the effect of voice notes from everything else, and they analysed ‘paralinguistic’ features (how something is said rather than what is said) such as tone, pitch, volume and speech rate.

The authors noted: “Voice notes allow physicians to communicate more information, present medical content less densely, and express greater empathy.

The study is from China but it’s relevant around the world, says Xu Zhang. The topline finding is that when physicians use voice notes, patients respond more positively.

“This is especially important in the healthcare domain, a sensitive domain where there is lots at stake,” says Xu Zhang.

Why did the voice notes have a positive impact? “Less jargon, more warmth,” explains Xu Zhang.

“When they were speaking rather than typing, doctors explained more, used plainer language and showed more empathy, and even their tone of voice made a difference.

“For the platforms, voice notes are a simple design feature that can improve patient experience, encourage follow-through on doctors’ recommendations and strengthen the ongoing patient-provider relationship.”

In addition, experienced physicians were more likely to use voice notes, and all physicians most likely to do so on days when they had heavier caseloads and for consultations later in their daily queue, consistent with the evidence that speaking is faster and takes less effort than typing.

The benefits were broadly consistent across the 10 medical specialities studied, with one possible exception: rehabilitation medicine, where patients who received voice notes were less likely to return to the same doctor.

There, Xu Zhang speculates that the patient seeking advice on exercises for rehabilitation following injury or surgery might need something different: precise, accurate information that they can come back to. “For patients in rehabilitation, precise instructions they can revisit may matter more than the warmth of a voice,” she suggests.

Lessons for leaders

There are some interesting takeaways here for non-medical services, says Xu Zhang, given chat-based support is the fastest-growing customer service channel.

“From banks to financial advisors, real estate to retail, more customer conversations now happen by chat. It has yet to be tested outside healthcare, but maybe voice will make it feel more human.

“If your human agents serve clients by chat, you could consider letting them send voice notes as well as text. You could also use AI tools to turn voice notes into structured text summaries, so clients get both the warmth of voice and the precision of text. Whether voice brings the same benefits to AI chatbots is still an open question.”

In financial services, where advisors need to talk to their clients about the kinds of products and services available to them, a voice note may be more reassuring than a text, Xu Zhang posits.

The other potential usage she envisions – her academic background is in marketing, after all – is in premium retailing, where emotional connection and resonance are as important as the high quality of the product itself. Voice notes may be particularly useful when a person needs more explanation or reassurance.

Within organisations as well, whether you are communicating in a group WhatsApp chat or on Teams, it’s worth considering what information might be best delivered by text, and when it might be more effective to use a voice note.

Voice notes are very different from ‘ordinary’ conversation in that they are asynchronous; you can pick one up and listen to it minutes or even hours after it is left. WhatsApp reported in 2022 that more than seven billion voice notes were sent on that platform every day.

At a time when we are increasingly using non-human intelligence to support us, it’s interesting to think about which of our interactions could still benefit from communication as old-school as a human’s voice conveying information into another person’s ear.

‘Beyond Text: How Voice Notes Shape Outcomes in Chat-Based Services’ by Xu Zhang and Yi Zhang is forthcoming in Management Science.