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Digital messaging to drive sustainable behavioural change

(Image credit: Image Credit: Gilles Lambert / Unsplash)

We take health knowledge for granted. Of course, we need to eat healthily, take vitamins and see a doctor if we are unwell. But many people in the world do not have that knowledge. They don’t understand that what we eat affects our health, haven’t a clue what vitamins are and a clinic or doctor may be hours away and cost money they do not have.   

Health message programmes delivered by mobile phone can change that. If you know what to feed your family to help them stay well and when to take them to the clinic you can make healthy choices. Often the changes needed are simple. In India poor families routinely feed their baby black tea and biscuit for breakfast. Not only is this nutritionally poor, but the tea inhibits iron absorption. Replace the tea with milk, and the biscuit with cereal and breakfast suddenly becomes a good start to the day.    

Results from our messaging programmes in the developing world have included increasing the percentage of babies taken for HIV testing, encouraging more women to have vaccinations during pregnancy, increasing the number of women taking iron tablets, and reducing the incidence of smoking in the house. 

Messaging is all about health education. Messaging programmes cannot build clinics, train doctors or supply vitamin pills. But they can and do change individual’s behaviour and in this sense technology is driving healthier lifestyles.   

Before you begin    

Before writing a mobile messaging behaviour change programme there are four key steps to consider: 

1. What will your programme change? Start with what you can change.  Many health mobile programmes skip this step and without it you just don’t know if your programme has succeeded. You cannot change everything at once so it’s very important to select some key issues and craft your messages to focus on those.   

2. What’s the most effective ‘dosage’. Our work in low resource settings has shown us that dosage matters. The wider to programme the more messages you need to send. A single issue messaging programme may only need a dozen messages. On the broad issues of maternal and child health, we found that two SMS messages a week for at least six months seems to be the tipping point.    

3. What are the barriers and motivators to change?  

Unless you learn about these, the chances are your programme will fail. Without knowing what barriers people have to climb, and what motivates people, you may spend time and money developing a programme that is ignored.   

4. How will you measure the change?   

It is useful to be able to prove that your messages changed things.  You may be able use national average figures as a baseline. Or you may be able to set up a control group. But since you have people reading your messages on their phone it makes sense to carry out short surveys by SMS. It’s worth doing an early survey so you can identify anything that needs changing early on.    

How do you write messages that work?   

Mobile phone SMS messages are very short. At 140 characters, every letter and every space counts. (We use 140 characters including spaces, to allow for translation into languages that come up longer than English.) Audio messages work best at around one minute (about 200 words). So, there is no room to qualify the information you include.   

Work carried out by BJ Fogg at the Persuasive Tech Lab at Stanford University provides a format to make effective behaviour change messages.  We have used these principles in the programmes we have developed which are now being used in six countries and we have added some ‘golden rules’ of our own.   

  • Messages need to be simple, direct and accurate. 
  • Break the change down into the smallest possible step. So, a handwashing message may need several steps…collecting water, buying soap, putting water near the cooking area, washing hands with soap, drying hands.   
  • Make each step as easy as you can. 
  • Make the emotional connection with the end user first. Once you have their attention, you can ‘drip feed’ vital information to them little by little. 
  • Re-iterate but do not repeat. We have found that people get annoyed if they are sent exactly the same message again. Or they think the programme has made a mistake.   
  • Keep it personal. The phone is intimate. You hold it in your hand and up to your ear. So use ‘you’’ and ‘your family’ not ‘the patient’.   
  • Use the words the consumer uses. You can add the medical word as well. That’s a good way of educating people. But if people in India say ‘sugar sickness’ for diabetes then your messages need to say that. 

Behaviour change at scale   

The real secret of a mobile phone based messaging programme is that it is both personal and scalable.    

A ‘pivot date’ means you can tightly target the messages to suit the individual’s needs. Our projects in India, China, South Africa and other countries have been on maternal and child health. Here the pivot date is the date the baby is due. We can then work out when vaccinations and clinic appointments are due and deliver just the right message in the right week. The same principle applies in other fields. If you are offering pre- and post-operative care information you can pivot around the operation date.  Or the date of diagnosis in the case of chronic diseases. You could even design a weight loss programme that alters the messages according to how much weight has been lost. Once you have developed the pattern of messages, you then target them according to where the end user sits on the ‘journey’ of your messages.   

Ultimately, it’s tempting to focus on the technology and many programmes do just that. But it’s vital to get the content of the programme exactly right first. Liebig's law of the minimum applies here. This was developed for agriculture and it states that ‘growth is dictated not by total resources available, but by the scarcest resource (the limiting factor)’. Content is often the limiting factor in mobile phone programmes, rather than the technology. Unless the messages engage people, resonate and help them make changes, they will not be read. The right content makes a mobile phone a lot more powerful.  

Daphne Metland, Director at Thrive   

Image Credit: Gilles Lambert / Unsplash

Daphne Metland
Daphne has set up a multi award-winning, international health editorial agency, Thrive and also co-founder of creative communications company, ubisend.