Sam Waller

Making the case for inclusive design

This paper describes the University of Cambridge, Engineering Design Centres (EDC) case for inclusive design, based on 10 years of research, promotion and knowledge transfer. In summary, inclusive design applies an understanding of customer diversity to inform decisions throughout the development process, in order to better satisfy the needs of more people. Products that are more inclusive can reach a wider market, improve customer satisfaction and drive business success. The rapidly ageing population increases the importance of this approach. The case presented here has helped to convince BT, Nestlé and others to adopt an inclusive approach.

Using disability data to estimate design exclusion

Exclusion auditing is a process that can quantitatively evaluate the inclusive merit of different products, or alternative design decisions. The results from such an audit can provide prioritised directions for product improvement and support the business case for reducing the capability levels required to use mainstream products. The 1996/1997 disability follow-up survey, conducted by the Office of National Statistics, is currently the most comprehensive data source for estimating design exclusion in the UK. In this paper, the data source is explained in detail, and a method is presented that uses this data to estimate the exclusion associated with several tasks that occur in series or in parallel, illustrated through worked examples. Having evaluated how many people are excluded, one can investigate why they were excluded, thus generating design insights into how they could be included. Data from the survey is also converted to a series of stylised graphs, which are intended to inspire designers to think about the relationship between the demands required to use a product and the resulting levels of population exclusion.

Quantifying Exclusion for Tasks Related to Product Interaction

Inclusive design aims to enable more people to use mainstream products, services and environments, especially those with minor ability loss. In this context, a mainstream product refers to one that is readily available “off-the-shelf” in competitive markets, produced according to economies of scale. However, there will often be an inevitable limit to the level of ability loss that can be accommodated by such designs, whilst keeping the production volume and styling suitable for mass-market sales at an appropriate price point. Setting appropriate targets for an inclusive design therefore requires understanding the trade-offs between the number of people who are unable to perform tasks that relate to different levels of ability loss, within all the types of ability that are required to interact with the product. Understanding these trade-offs requires a single data source that covers all of these types of ability loss, yet the 1996/97 Disability follow-up survey (DFS) (Grundy et al., 1999) remains the most recent UK dataset that covers all such aspects of ability loss (Johnson et al., 2009).

Approaches to estimating user exclusion.

The success of a product may be measured in many different ways, including: the commercial impact it has on the business that brought it to market; the market share attained; the prestige afforded to the design team; the number of awards won; the delight brought to the customer; the number of repeat purchases; and possibly even the usability of the product. Few products achieve success in all these areas, but successful companies are likely to excel in many. For example, Lego was the world’s sixth largest toy maker in 2006 (Design Council, 2006) and remains an extraordinary success story, based on consistent quality, cost effective delivery and innovative product offerings. However, few know the names of the product designers or the original inventor, Ole Kirk Christiansen. Conversely, many know the name of Apple’s design chief, Jonathan Ive, who was responsible for the revolutionary, and hugely successful, iMac, iPod, iPhone and iPad. The success of a product can also be measured in terms of its accessibility regardless of its market success. Although, too often products succeed in the market place, despite real challenges to usability, due to a lack of credible competition or poor styling of more accessible alternatives. For example, early handheld hair driers were both heavy and bulky, while later products became lighter, smaller, quieter and more attractive. As markets move towards saturation, usability can become a useful means of differentiation. The Ford Focus and Oxo Good Grips range of kitchen utensils are examples of innovative, appealing, profitable and, most importantly, accessible design. Yet as we recognise such examples of good design, standard measures of usability outside of the web community remain rather elusive. This paper reflects on the development of a number of approaches to defining andmeasuring accessibility that have emerged from the work of the iwdesign research consortia over the past decade.

Understanding the Co-occurrence of Ability Loss

Many solutions for one kind of ability loss rely on another kind of ability to compensate, so understanding the co-occurrence of ability loss is critical when designing or specifying products, services or environments that should be accessible to, and usable by, the widest possible range of people. For example, a common solution for vision ability loss is to provide supplementary audio information, yet the success of this strategy will depend on the extent to which people who have vision ability loss do not have hearing ability loss.

Do best practice guidelines improve the legibility of pharmacy labels for the visually impaired

Citation information: Latham K, Waller S & Schaitel J. Do best practice guidelines improve the legibility of pharmacy labels for the visually impaired? Ophthalmic Physiol Opt 2011, 31, 275–282. doi: 10.1111/j.1475‐1313.2010.00816.x

Design and delivery of a national pilot survey of capabilities

Understanding the numbers of people with different levels of ability in the population is important for informing design decisions for mainstream products, but a survey dataset for this purpose does not exist. This paper describes a key step towards obtaining such data. It describes a pilot survey of 362 people across England and Wales in preparation for a full national survey. Information was gathered on vision, hearing, hand and arm function, mobility, cognitive function, product use, psychological characteristics, anthropometrics and demographics. An interesting finding is that of those participants who reported any limitations in daily activities due to capability loss, 44% reported limitations due to loss of more than one capability. This finding highlights the importance of measuring multiple capabilities in a single survey. Top-level lessons learnt include: simplifying vision tests; reducing exclusion criteria for some of the tests; adopting a stratified sampling approach; and allocating more training for interviewers.

Visualizing Design Exclusion Predicted by Disability Data: A Mobile Phone Case Study

Disability data can help to predict the number of people that will be unable to use a particular product. The greatest benefits of this prediction are the design insights that help to reduce exclusion and thereby improve the product experience for a broad range of people. This paper uses a mobile phone case study to demonstrate how a set of visualization outputs from an exclusion audit can generate prioritized design insights to reduce exclusion, particularly when multiple tasks place demands on multiple capabilities.

A Population Perspective on Mobile Phone Related Tasks

For design to be truly inclusive, it needs to take into account the range of users’ capabilities. To do this appropriately, good data on those capabilities is needed. This paper reports on results from a postcode sampled survey of 362 people. The survey examined a wide range of user capabilities and characteristics, but the paper focuses on just a few of the survey measures. These measures examine some of the component activities involved in using mobile telephones: selection of a menu item via two different interaction patterns, use of differing sized pushbutton controls and insertion of two different types of electrical connector. These results can help to inform more inclusive design of mobile phones by examining how people’s capability to perform these activities varies across different activities and by age and gender.

Converting Disability Data into a Format Suitable for Estimating Design Exclusion

The Cambridge Engineering Design Centre is unique in developing analytical tools that can quantitatively assess the inclusive merit of different design decisions, according to the number of potential users that would be excluded: such tools would greatly assist the implementation of inclusive design in businesses (Dong et al., 2003). In addition to those excluded from using a product, many more people will experience difficulty or frustration, so reducing the number of people excluded can improve the experience for a wide range of users. Indeed research commissioned by Microsoft (2003) reported that “60% of Americans aged 18–64 years were likely or very likely to benefit from the use of accessible technology”.