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Human Factors and Usability Services
What is Usability?
Usability addresses the relationship between tools and their users. In order for a tool to be effective, it must allow intended users to accomplish their tasks in the best way possible. The same principle applies to computers, websites, and other software. In order for these systems to work, their users must be able to employ them effectively. What makes a product usable?

Usability depends on a number of factors including how well the functionality fits user needs, how well the flow through the application fits user tasks, and how well the response of the application fits user expectations. We can learn to be better user interface designers by learning design principles and design guidelines. But even the most insightful designer can only create a highly-usable system through a process that involves getting information from people who actually use the system. Usability is the quality of a system that makes it easy to learn, easy to use, easy to remember, error tolerant, and subjectively pleasing.

Why is Usability Important?
From the user's perspective usability is important because it can make the difference between performing a task accurately and completely or not, and enjoying the process or being frustrated. From the developer's perspective usability is important because it can mean the difference between the success or failure of a system. From a management point of view, software with poor usability can reduce the productivity of the workforce to a level of performance worse than without the system. In all cases, lack of usability can cost time and effort, and can greatly determine the success or failure of a system. Given a choice, people will tend to buy systems that are more user-friendly. How Do You Achieve a High Level of Usability?

The key principle for maximizing usability is to employ iterative design, which progressively refines the design through evaluation from the early stages of design. The evaluation steps enable the designers and developers to incorporate user and client feedback until the system reaches an acceptable level of usability. The preferred method for ensuring usability is to test actual users on a working system. Achieving a high level of usability requires focusing design efforts on the intended end-user of the system. There are many ways to determine who the primary users are, how they work, and what tasks they must accomplish. However, clients' schedules and budgets can sometimes prevent this ideal approach. Some alternative methods include user testing on system prototypes, a usability inspection conducted by experts, and cognitive modeling.

Where is Usability Applied?
Usability is one of the focuses of the field of Human-Computer Interaction. As the name suggests, usability has to do with bridging the gap between people and machines. A user interface (or human-computer interface) refers to the parts of a hardware and/or software system that allow a person to communicate with it. This includes output devices (the way the computer talks to a user) and input devices (the way a user talks to the computer). Typical "output devices" include computer monitors and the windowing systems that run on them, but also include speakers and other devices that provide feedback. "Input devices" include peripherals like keyboards, mice, and joysticks, but also include microphones and even eye movement devices. Each of these interface components have devices corresponding to the visual (sight), aural (sound), and hepatic (touch) channels of the brain. Usability engineering studies these elements of the user's experience.

Human Factors Methods
There are a variety of approaches to usability evaluation that you may choose to take that Renfro Consulting provides. The methodologies can be divided into two broad categories: those that gather data from actual users and those that can be applied without actual users present. Of course the approach you choose to take must factor in variables such as the cost of evaluation, the appropriateness of the technique to your project, time constraints of the project, and the cost associated with the implementation and training of new users.

Usability evaluations can be conducted at many stages during and after the design and development process. In choosing a usability evaluation method, cost is invariably a consideration. But it is important to keep in mind that the value of a usability evaluation needs to be calculated not only in time and materials involved, but also in terms of the impact on the end-users, especially considering the cost of losing return visitors to your website due to unusable design.

Methods Section Overview
  1. Cognitive Walkthrough is an approach to evaluating an interface based on breaking down and analyzing actions that a user must perform in order to use the system or perform a task.
  2. Focus Groups gather groups of users to get their feedback, initial reactions to a design, and discuss their preferences. Focus groups can be useful for raising issues that may not come out during interviews.
  3. Prototyping involves developing representations of a system for testing purposes and can range from simple sketches to almost fully functional systems.
  4. Task Analysis evaluates how the end-user actually uses software or websites. An analyst determines the user goals and tasks, then makes recommendations aimed at increasing efficiency and user-friendliness.
  5. Usability Inspection reviews a system based on a set of usability guidelines. Experts familiar with issues of usability in design perform the usability inspection.
  6. User Testing observes actual users interacting with software or websites. Users are asked to perform tasks while usability experts observe and take note of their actions.

Cognitive Walkthrough
Cognitive walkthroughs are performed at any stage of design using a prototype, a conceptual design document, or the final product. This is a more specific version of a design walkthrough, focusing on cognitive principles. Based on a user's goals, a group of evaluators steps through tasks, evaluating at each step how difficult it is for the user to identify and operate the interface element most relevant to their current sub-goal and how clearly the system provides feedback to that action. Cognitive walkthroughs take into consideration the user's thought processes that contribute to decision making, such as memory load and ability to reason.

For example, finding this website can be broken down to several levels of tasks. At a general level, it requires opening up a browser, remembering the URL and typing it in the text box at the top of your browser. Or, if you do not remember the URL, you must choose a search engine, think of a search term, view the results, scroll through the results, and then click on the link. Each of these actions can be further decomposed.

This approach is intended especially to help understand the usability of a system for first-time or infrequent users, that is, for users in an exploratory learning mode.

Focus Groups Using focus groups to evaluate a system is a very efficient way to get user feedback and gauge initial reactions to a design. Focus groups are also good at discovering how the system being tested differs from the user's current expectations. As we see it, focus groups provide two major benefits. First, they are less expensive than conducting interviews with the same number of people. Second, they rely on group interaction to trigger memories that may not come up during interviews.

Where task analysis often discovers the standard way people interact with information systems, focus groups can bring out exceptions to the rules. These exceptions are often very important interactions that users simply do not think of in one-on-one sessions.

Conducting only a single focus group can be misleading, however, as some groups are affected by "group-think" or may simply have irregular views. For this reason, at least two groups should be evaluated for any one project. The focus group leader writes up the impressions and comments of the groups and recommends areas for improvement.

Prototyping
Prototyping techniques involve developing representations of a target system for evaluation and testing purposes. Prototyping is an essential element of an iterative design approach, where designs are created, evaluated, and refined with the results of testing at each cycle feeding into the design focus of the next cycle. Prototypes can range from extremely simple sketches (low-fidelity prototypes) to full systems that contain nearly all the functionality of the final system (high-fidelity prototypes).
Here is a list of some prototyping terms and techniques:
  • thumbnail sketch
  • rough
  • comp / mockup
  • paper prototype
  • video prototype
  • wizard of oz prototype
  • functional prototype
  • rapid-prototyping
Task Analysis
Task analysis is a method that evaluates how people actually accomplish things with software. Through observation and interviews with users, an analyst determines a set of goals belonging to the target user. Then, a set of tasks that support these goals is determined. These are prioritized based on criteria such as the importance of the goal to the organization and the frequency of task performance.

The highest priority tasks are decomposed into their individual steps. The level of decomposition varies with the budget and type of system evaluated. The analyst then suggests ways to make the task more efficient or suggests new tasks which more effectively support the goals. It is important to recognize that the analysis is done from the perspective of the end-user-not from the point of view of managers or executives who do not necessarily use the system

Usability Inspection A usability inspection is a review of a system based on a set of guidelines. The review is conducted by a group of experts who are deeply familiar with the concepts of usability in design. The experts focus on a list of areas in design that have been shown to be troublesome for users.

Usability guidelines are usually derived from studies in human-computer interaction, ergonomics, graphic design, information design, and cognitive psychology. Some areas that get evaluated are the language used in the system, the amount of recall required of the user at each step in a process, and how the system provides feedback to the user. In particular, issues such as clarity, consistency, navigation, and error minimization are analyzed. Once the problems are discovered, the experts make recommendations for resolving these issues.

User Testing
User testing is the mainstay method when it comes to finding usability problems. Nothing is more convincing than watching person after person encounter difficulties with the same part of a software or information system. The difficult areas that repeat themselves between multiple test participants reveal areas that should be studied and changed by the developers. User testing can often uncover very specific areas needing improvement, where focus groups and task analysis often find more general areas needing improvement.

A trained observer conducts user testing often with the assistance of software developers. People who are representative of the target audience are asked to perform representative tasks with the software. The observer writes a user testing report listing the problems and offering recommendations based on their findings.

Just as computers vary by operating system, processor speed, screen size, memory, and networking abilities, users vary in ways both expected and unexpected. Some differences that are more commonly thought of are language, gender, age, cultures, preferences, and interests. But some of the differences that need to be addressed more by the software and web development community are skills, ability levels, and constraints under which users may be operating. Designing for diversity not only increases the number of people able to access your software or website but also increases their level of involvement with it. Barrier-free design is beneficial for all users. Designing for universal access is not only good social practice, but in general, it is good business practice.

Accessibility Services
Who is affected by accessibility?
1 in 5 people in the United States has some kind of disability and an estimated 30 million people are impacted by inaccessible computer and software design. The number of people with disabilities is only increasing, as it has increased 25% in the last decade, especially among those 50 years old and above. And among the 31 million seniors aged 65 and above, 16 million reported some level of disability (Census Brief 97-5). But accessibility actually affects a much larger percentage of the population, as many people who do not have permanent disabilities have temporary conditions that can affect the way they operate for a period of time. And beyond that, the very young and the very old can also benefit from more accessible design. With this in mind, accessibility in website design should really be thought of as part of universal design.

The internet and accessibility
The internet has the potential to broaden the lives and increase the independence of people with disabilities. For people who can be physically as well as socially isolated, access to the internet can offer information about, social interaction, cultural activities, employment opportunities, and consumer goods. But, as statistics demonstrate, not as many people with disabilities are able to take advantage of these possibilities, in large part because their needs have not been addressed by the web design community.

In 1996, the Department of Justice determined that the Americans with Disabilities Act applies to Internet web pages. The Department of Justice is backing lawsuits filed across the country against websites that do not conform to Title II and Title III of the ADA. The Telecommunications Act of 1996 also includes legislation to enforce standards in converging technology, wireless communications, and emerging technology. And beginning in June 2001, all new federal websites must conform to Section 508 of the Rehabilitation Act of 1973.

Who's interested in accessibility?
The legal ramifications are not the only reasons for compliance with accessibility standards, however. There are many market sectors that are interested in sites that conform to accessibility standards, such as:
  • Government
  • Education
  • Libraries
  • News groups and online periodicals
  • Public utilities and transportation
  • Hospitals
  • Banking, bill payment
Who benefits from accessibility?
The public sector is not the only area that benefits from more accessible websites, software, and hardware. Any business that wants a larger market share should be interested in making their products more accessible.

Many of the issues raised by advocates of accessibility are addressed by the "universal design" approach. Universal design calls for developing products that accommodate the broadest range of users regardless of age or ability. It calls for design that is usable for everyone without needing special alterations or adaptations for accessibility. The benefits of universal design in products extends beyond the elderly or disabled populations. Universal design also addresses many of the issues that arise in internationalization, which is becoming increasingly important in today's marketplace. Some of the key elements to universal access are: providing for interoperability with many applications; providing accessibility to the disabled; and providing customization and localization features for people from different countries and cultures

Renfro Consulting can evaluate your product and create the VPAT documentation used to show the level of accessibility compliance. This can then be used to market to governmental agencies and other customers who require accessibility testing and verification.

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