1.3 Benefits and consequences of interaction design
Although not everyone will wear the Bubelle dress or use an EEG headset to play computer games, technologies such as smartphones and computer tablets are becoming an increasingly significant part of daily life for millions of people. The following activity asks you to try to quantify just how big a part technology plays in daily life.
Activity 1 Exploring daily usage of interactive devices
Search the internet for market information or estimates about how many hours adults spend using computers (including laptops and tablets) and smartphones each day. See if you can find figures for more than one country. How accurately do you think these figures reflect your own usage?
In addition to computers and laptops, there is a wide range of other, perhaps less glamorous, interactive products which many people use daily. We may not pay much attention when we use coffee machines, toasters, dishwashers, elevators, automatic doors, car dashboards, vending machines, and so forth, yet without these technologies doing things for us, our daily lives might be very different.
Do you think you are fully aware of the role that interactive technology plays in your life? Below is an activity that will help you answer this question.
Activity 2 My typical day - interactive devices
Choose a typical day in your week and a typical hour in that day. Make a note of all the times you use an interactive product, whether it is a phone, tablet or laptop, alarm clock, cash machine or car. If you use a device multiple times, note it each time. For each interaction, note the following information:
- what device you use
- what you use it for
- how long you use it for
- how easy you find the interaction
- whether you enjoy the interaction
- whether you would have noticed the interaction without being asked to think about it.
Take a moment to reflect on what you observed. How typical was this hour? If you look back over the preceding 24 hours, how might it compare? What other devices come into play? How many of the interactions are frustrating or problematic?
This exercise should give you an idea of the time you spend using interactive products and therefore how much a part of your daily experience these interactions are. It should also help you reflect on the range of activities and tasks that interactive technology enables you to do and what difference that makes in your day. Finally, it should help you think about how you experience those interactions – whether the interactive products are readily usable, and what contributes to a good or bad experience using them.
Compile an overview: add up how much time you spent using interactive devices overall, how many devices you used, and how many of those you used repeatedly. Which device did you use the most? Was any interaction particularly frustrating?
As a worked example, this is an hour in a typical day in the office complete with an overview of my interaction with a number of these things.
|Device and what happens||How often and total duration||What’s it like|
|Phone – gives BBC news notification||
|It beeps in my handbag and is a bit annoying, as the noise of the phone disrupts me from what I’m doing.|
|Phone – send a message to colleague to check whether meeting is on||
|Good. Quick way of checking things, because starting my email can sometimes take ages due to poor Wi-Fi in my workplace.|
|Laptop – check whether meeting is on Skype||
|OK. Depends on whether Wi-Fi is up and running. I can see that other people are not online which is good to know.|
|Laptop – check email||
|Email has become second nature to me. I use it the whole time. I can’t remember anymore whether it is a good experience or not – it is what it is.|
|Door – opening with RFID security tag||
|Getting in through the main door is tricky as I have two bags in my hands and find it awkward to swipe the card with my hands full. Later, door access is OK because I’ve got rid of my heavy bags.|
|Laptop – open documents in Word||
|Opened attachments to mail in Word. Unfortunately Word crashed, so not a very good experience. This has happened a lot to me recently.|
Doing this activity makes me realise that I often work with several devices on the go – my laptop and phone are side by side. My phone is my own personal device but I use it for work purposes.
Many of my interactions with normal office applications – Word, email and Skype are not particularly pleasant. I struggle with lousy Wi-Fi, which slows things down – and applications crashing on my machine. Again, not a good experience.
With an application like email, I find it hard to reflect on whether it is a good experience or not, as it is so much a part of my life that I can’t distance myself from it to provide an opinion.
The above overview is representative for a working day in the office. Working days can be made more complex by (i) using coffee machines (ii) overhead projectors and other big screens when doing presentations (iii) sharing large files with colleagues through a range of methods. When I am at home, and I do often work from home, a different set of things needs to be added – such as kitchen apparatus.
My laptop is the device I used most of all. It is what I use for all my work, which is reading or writing. However, its use is not straightforward.
If during the above activity you found that you do use interactive products often but take them for granted, that is because the design allows you to focus on what you want to do rather than having to focus on the interaction itself. Yet each interactive product has a user interface, where the interaction between user and interactive product happens, and each interface and interaction has been designed. In other words, good interaction design supports your activities and enables you to do what you want to do easily, quickly and correctly without getting in the way, supporting a natural and engaging interaction between users and products. Unfortunately, not all interactive products meet this standard.
As you might have experienced, there are indeed consequences to poor interaction design. For example, it may take longer to do things, it may be so frustrating that one might give up altogether, or worse it may result in costly mistakes. A poorly designed thermostat may result in users inputting the wrong settings and wasting money on their heating bill.
Poor interaction design may also result in financial losses for companies that use interactive technology during the production of goods. If employees struggle to use their work tools, their productivity may be drastically reduced, thus increasing production costs. Additionally, interactive technology that is difficult to understand and use may also require more training, which also comes at a cost.
At the same time, if a company produces interactive products that are poorly designed, it may incur severe financial losses following the products’ commercial failure.
However, the costs of poor interaction design are not limited to daily inconvenience for individual users or financial losses for large organisations. There are numerous instances in which poor interaction design has been responsible for accidents that cost lives. The bad design of interactive products that are used for healthcare purposes, either in emergencies or during routine activities, provides a poignant example. In particular, in the video in the next activity, Professor Harold Thimbleby, an expert in the design of safe interactive medical devices, talks about the importance of good design to prevent or accommodate human error. The video illustrates how even the most trivial interaction errors can lead to tragic consequences, for example, when using blood infusion pumps to administer medical treatment to patients with life-threatening conditions.
Activity 3 Saving lives by design
Watch ‘Saving Lives by Design’ below and answer the questions that follow.
Transcript: Saving lives by design
HAROLD THIMBLEBY: Let's go to the beach. And it's a lovely day, and there are people playing. Just suppose some of them got into difficulties. You'd want to call the coast guard to get the help you need. I've got a mobile phone. We tend to think our mobile phones are wonderful-- technology is wonderful.
Well, what's interesting is I choose this and I like it, but very often we have to use devices we can't choose. Well, let's try and call the coast guard. Maybe you don't have coverage on your mobile phone, so you're going to run to use the coast guard phone.
The coast guard phone-- you can see on the sign that it's saying call 999. 999 is the right number to call to get the coast guard. It says 1 2 3. How are we going to dial 999? That's guaranteed we're going to take longer. I'm confused. I don't know what to do. I can't dial 999. I was told to dial 999. What do I do?
Well, there's a really interesting thing going on here-- that somehow the Coast Guard has put a 999 phone on the beach for everybody to use, and you can't do that. Something's gone wrong with the design. Here it's really obvious that it's gone wrong.
Possibly the coast guard don't notice because, of course, the only people who ring them up have succeeded in using it, and they're not going to say, oh, there's a design issue here. They're going to say, come and rescue the kids who are drowning. So it's an obvious design problem, but nobody knows about it.
In hospitals, everybody makes slips. And obviously what's good about hospitals is everybody's professional and those slips gets sorted out. What worries me is people make slips and the technology isn't part of the team that stops those slips turning into catastrophes.
And the cash machine is a really good example of how the catastrophe of losing your cash card is a problem that's been fixed by redesigning the cash machines so that you can't leave your card behind. Because you don't leave it behind now. You want your money. That is a good illustration of how redesigning infusion pumps and calculators and stuff like that would make hospitals a much safer place.
Denise Melanson was a cancer patient who died from an overdose of fluorouracil. Fluorouracil is a chemotherapy drug, and you want to get the right amount of it, and it's really critical to get the right amount. If you have too little, it doesn't kill the cancer. And if you have too much, it kills the patient.
And unfortunately, a mistake was made, and I want to explore what the mistake was. I'll tell you what the story is. Denise Melanson was what's called an ambulatory patient. She was walking around with this infusion pump and a bag of fluorouracil. So this is really nice. It means you can walk around. You're not stuck tied to a bed.
Her bag of fluorouracil runs out, and she goes to the Alberta Cancer Care Centre to get some more drug. And the nurses go to the pharmacy. They get another bag of fluorouracil, and they have to calculate how much fluorouracil the pump is going to give her. And it should have been 1.2 millilitres per hour. They accidentally forgot to divide by the number of hours in a day, so they ended up with 28.8 mils per hour.
Denise Melanson should have come back four days later with an empty bag. Instead she came back four hours later. And basically, she'd be given an overdose of fluorouracil and that killed her.
What went wrong? There are several things that went wrong. One is the way the calculation was done. It's actually very difficult to do the drug dose calculation. And the best I can do is it takes 22 keystrokes on a calculator. If you make any slip while you're doing that calculation, you just get the wrong result.
If you're using a calculator, the whole point using a calculator is you don't know what the right result is. So if you make a slip and get the wrong result, you don't know. So here, they made a slip. They forgot the 24 hours in a day. The calculator had no idea what they were doing, and it just gave them the wrong answer.
The normal take on this is that the nurses should be trained to do the sum properly. My take on it is why are they using a calculator that doesn't know what they're doing? It's easy enough to set up the device. These infusion pumps can do that sort of sum. And in fact the bag of fluorouracil the nurses were given said 1.2 millilitres per hour on it. There's actually no need for them to do the calculation at all.
But the point is, if they make a slip-- and from time to time, everybody will make a slip-- the calculator doesn't help. This is the infusion pump that Denise Melanson was using. The root cause analysis, the study of why she died included a study of this pump. Five nurses from the ward where she was treated were taken for two hours to study how to go through the same scenario that ended up killing Denise Melanson.
Basically, none of the five nurses they had in that two hour study could use this pump effectively. They had problems with it. One of the obvious problems is the decimal point is the same as the up arrow key, and that confuses nurses.
The conclusion that the root cause analysis had is that the nurses need to be trained to use the pump. That seems like an obvious comment to make, like, you've got these things-- people ought to be able use them.
I'm interested in design. And the different issue is, why didn't the manufacturers do a two hour study with five nurses and find out that they're selling an infusion pump that people can't use? They could've redesigned it so that it was easier to use. And it only takes five nurses for two hours, and you discover all sorts of problems with it. Those problems should have been fixed before it was sold.
I'm arguing that design can make things safer. There are two sorts of infusion pump, and the question is which design is better? There's one sort like the pump I've just show you which has got a calculator keypad on it. If you want to enter a number like 12.3, you key in 1 2 point 3. But you key in the digit. The other sort is an incremental keypad, whereas if you want to 12.3, you press up and down, and you gradually increase the number to 10, and 12, 12.3, or you decrease it 100 down from 90, 80, 70 to 12.3.
So one sort of infusion has up/down keys to increase or decrease a number. The other sort has got a keypad on it with 10 digits and a decimal point, and you type in the number that you want. Which is better?
We've done some experiments, and it turns out that the up/down keypad is twice as good. And the reason for this is if you're using a numeric keypad, you want to enter 12.3 or whatever number, you just press the keys. Your eyes are looking at the keypad. You don't look at the display because you know what you're doing. You look at the keypad because you need to know where to put your fingers. If you make a slip, you don't notice.
With the up/down keypad, you hardly need to look at the up/down keys because you know where they are. You need to look at the number. And of course, you keep on adjusting the number until it's right. And unsurprisingly, when you think of it like that, you end up with being more accurate and more reliable if you use the up/down keypad.
So that's a simple example where an experiment tells you one sort of design is twice as good as the other sort of design in terms of error rate. The point is, if the technology is re-designed to detect errors, then everybody could do a much better job. At the moment, technology ignores errors and it does anything. We've done some peer reviewed papers that showed that if you detect errors in this process, you can halve the death rate.
I've given you a few examples of how bad design leads to problems from the coast guard phone on the beach to infusion pumps, calculators, up/down keypads. You can redesign things to make them safer and better support the tasks that people are doing.
In health care, you've got IT systems and gadgets that are letting nurses and patients down. They're killing people and nurses are getting sacked rather than solving the design problem. I'm on a mission to get this message out-- that everybody needs to be aware that the technology that we're using could be a lot better.
- a.What design problem is highlighted with the example of the coast guard emergency phone?
- b.What error did the nurse make when setting the infusion pump and why? Is this a human error or something else?
- c.Which of the two infusion pump designs discussed in the video is safer and why?
- a.The coast guard phone sign asks users to do an action (dial 999) for which there is no input device (the only keys are 1, 2 and 3). There is therefore a mismatch between the activity that the user wants to do and the interface, which does not support this activity. When people are using devices with which they are unfamiliar, it is particularly important that they are understandable.
- b.The nurse inputted a drug release rate into the infusion pump that was 24 times higher than it should have been. She used a calculator to calculate the release rate but forgot to divide by the number of hours in the day. The calculator did not know this or what the correct rate should have been, so it did not alert the nurse to the error. Such an error is often considered to be a human error, i.e. something that the user did wrong – rather than an error made by the machine. In this case, the error could have been avoided by an inbuilt calculator specifically for the purpose of this pump. The point of the video is to show how rather than considering such mistakes as human errors, that these are design faults, where the design of the device has not taken on board who will be using it and for what purpose. In the case of medical devices, such design decisions can be a matter of life and death.
- c.The safest pump design was the one that featured up and down arrows as input mechanisms, because that forced users to look at the display rather than at the keypad, and because they could only make incremental adjustments. It is interesting that such a subtle difference – i.e. where the users will focus during the interaction – can make such a difference.
This section should have given you an idea as to why interaction design is so important, what consequences poor interactions can lead to, and conversely, what benefits good interactions can provide.
But what makes a design good or poor? What makes interactive products succeed or fail? In other words, what is interaction design all about?
The following activity is designed to help you think about these questions.
Activity 4 Experiencing and designing for different capabilities
This activity is about exploring and experiencing what it is like to operate everyday devices when the user has quite different capabilities. It is important that you carry out all aspects of this activity, as you need to be able to refer back to your experiences while studying this section.
- a.Select an everyday device that you might use on a regular basis and carry out a straightforward operation that you normally do. For example, try composing a short text message with your mobile phone, making a phone call with your home phone, or operating your TV using a remote control.
- b.Now, try doing the same while wearing thick gloves; if you don’t have these, try putting your hands into very thick socks. This is to simulate constraint: for example, you might be on a ski slope wearing heavy gloves, or you might have no fingers, or you might have very large fingers with little dexterity.
- c.Make a note of the difficulties that you experience (if any) and why you think you are experiencing them. Now think about what you need to do in order to fulfil the action you’re attempting. What properties would the device need to have in order for you to carry out the action, given the constraints of the glove or sock?
- d.Now think about how you might alter the controls in order to meet your needs. Can you think of more than one alternative?
- e.Now, using pen and paper, try drawing one of the alternative versions of the controls that you have considered.
- f.Try ‘interacting’ or pretending to interact with your sketched device while wearing thick gloves or socks. Are any improvements needed? If so, think again about what you need and what changes you think are necessary to meet those needs, and then draw the controls again and try them out.
- g.Make a note of the changes you would make to the original device and why you think these would be necessary to enable you to use it.
For this exercise, I tried using my old Motorola mobile phone while wearing my big oven gloves (Figure A).
Of course, the flat keypad of this particular model of phone makes it impossible to press the keys with precision with the gloves on, so I had to think of a different keypad. To have something to compare my drawings to, I first drew the phone’s keypad more or less to scale (Figure B).
My first modification to accommodate the fact that I was wearing mittens was a reproduction of the same keypad in a larger scale (Figure C): this worked a lot better with my gloves, but it meant that I would have to go around with a huge phone, which I was not happy about.
To reduce the size of the keypad and still be able to use it, I had to reduce the number of keys, so I had to rethink the way in which the keypad was organised (Figure D).
In my reorganised keypad, each function only has one key (e.g. there is only one ‘enter’ key instead of two and users have to select options to enter via the arrows at the top of the keypad) and some keys can be used for multiple choices (e.g. ‘up and down’ keys can be used to choose different letters and numbers … I copied the idea from the infusion pump interface, described by Professor Harold Thimbleby in Activity 4). This arrangement and reduced number of keys means that I need to press the same key multiple times (e.g. when I want to bring up a particular letter) or for different durations (e.g. the ‘left’ and ‘right’ arrows at the bottom of the keypad could be used to move the cursor left or right if pressed quickly, or to delete letters and numbers if pressed for longer). This is less convenient, but it means that I can still have a phone of a reasonable size and that I can use it while wearing the mittens.