Usability, Learnability, Memorability

This entry is part 1 of 12 in the series Medical Computing

(A version of this series was first published in the newsletter of the Informatics Section of the American College of Emergency Physicians)

Those of you who know me (or maybe have just heard about me) know that I am a zealot about user interface design. With good reason! Those who think they are computer-illiterate are wrong; it’s their computers that are human-illiterate.

Software has gotten better over the years, but, truthfully, it’s still really, really bad. Mainline software such as that from Microsoft has – through usability testing, which is a key concept – gradually evolved to where it is reasonably good software. But ED software and other niche products have arguably lagged, due at least in part to the costs of usability testing. Have you ever cursed a computer or punched a monitor? (Be honest now!) Have you ever used a new computer or a new program that:

  • was just right for your needs,
  • worked perfectly out of the box,
  • had no need to look at manuals or online help,
  • improved your productivity right away,
  • provided nice new functions that you didn’t even know you needed, and
  • was as much fun as a good computer game?

Well, these are rhetorical questions, but they shouldn’t be. We need to raise our expectations of our computers and software. Read the rest of this entry


Tognazinni’s Paradox

This entry is part 2 of 12 in the series Medical Computing

In the first of this series, I tried to persuade you that your computer is human-illiterate. We discussed ways that people try to improve this, including usability testing. I introduced you to Alan Cooper’s About Face: The Essentials of User Interface Design (you did go out and buy it and read it, didn’t you?) which included such bon mots at “No matter how cool your interface is, less of it would be better.” I introduced you to Jakob Nielsen, his book Usability Engineering, and his online columns. Next, we went on to put usability into its place in Neilsen’s schema of overall acceptability of a program, including such other factors such as cost and reliability. We then reviewed the five components of usability:

1)       Ease of learning

2)       Efficiency of use

3)       Ease of remembering

4)       Rate of error during use

5)       Subjectively pleasing

We went on to learn about Learnability and Memorability (and, I hope, in a learnable and memorable way: remember the Kiss-and-Ride signs?)

OK, enough recapitulation, and on to: Tognazzini’s Paradox. Let me now introduce you to Bruce Tognazzini, AKA “Tog,” who was the Apple Computer User Interface Evangelist (yes, this was an official Apple Computer title). In the early days of Apple, he was responsible for much of the Mac’s interface that was laudable. (We will not talk about how much of it was stolen by Microsoft for Windows, or contrariwise how much Apple stole from the Xerox Palo Alto Research Center (PARC). Anyway, Tog was and is famous for his innovations and even more for his insights about computer user interfaces. His book Tog on Interface is an updated collection of his columns – highly recommended reading. As soon as you finish Cooper’s book, start reading Tog’s book. Read the rest of this entry


Design Integrity, Simplicity and Abstraction

This entry is part 3 of 12 in the series Medical Computing

In the first of this series, I tried to persuade you that your computer was human-illiterate, and we defined and discussed usability, memorability, and learnability. In the second, we discussed Tognazzini’s Paradox: how the hardest part of designing an effective program is often what seems the most trivial – sometimes simply a matter of changing a single word.

The Famous View of Fallingwater

The Famous View of Fallingwater

Now, we should discuss design integrity, and in particular, simplicity and abstraction.

Integrity is easy to identify, hard to explain. Let me give a few examples and make an attempt at explaining.

First, Frank Lloyd Wright. National and international associations of architects have acclaimed one of his houses the most important building of the 20th century: Fallingwater. Fallingwater, a house he built for the Kaufmann family of Pittsburgh, is the finest example of his “organic” architecture. Wright considered organic architecture to be what is entirely appropriate to its place, its time, and its user. Having Bear Run go through the living room, and building the room out over the waterfall, sounds like an exercise in spectacle. Yet anyone who has been to Fallingwater (something I highly recommend – and while you’re there, also visit his house Kentuck Knob, open for display about 10 miles away – make sure you visit the sculpture gardens by walking about half an hour down the hill to the entrance buildings) can understand that is is actually a very understated house – there isn’t a bit of spectacle. The irregular, staggered horizontal lines of the house mesh with the flat-bedded stone of the Bear Run ravine, and the house seems to be a natural extension of Laurel Mountain’s bones rather than something imposed on the landscape.

Conover House Back View

Conover House Back View

I strongly recommend that your visit to Fallingwater also include a day-hike in the surrounding Bear Run Nature Reserve, so you can get a feel for Pennsylvania’s Laurel Highlands, the western edge of the Appalachian Mountains and a just lovely area to hike. But be prepared for wet weather – the top of Laurel Ridge to the east is a temperate rain forest. It’s about an hour’s drive from my house in Pittsburgh, which was the house and architect’s studio of one of Wright’s pupils, and for years its renovation has been taking more than all my time, effort and energy, but it at least shows I truly buy into this “organic” idea. Read the rest of this entry


Discount Usability Testing

This entry is part 4 of 12 in the series Medical Computing

In the first of this series, I tried to persuade you that your computer was human-illiterate, and we defined and discussed usability, memorability, and learnability. In the second, we discussed Tognazzini’s Paradox: how the hardest part of designing an effective program is often what seems the most trivial—sometimes simply a matter of changing a single word. In the third, we talked about design integrity, simplicity and abstraction. Now, let’s address “discount usability testing.”

When we talk about “usability testing” most of us think about expensive consultants, fancy labs with one-way mirrors and video recorders, and the like. Yes, usability testing can be done in such labs. Yes, companies like Microsoft have permanent million-dollar user testing labs.

But if you design, program or provide feedback on any portion of an ED information system – learn how to do some discount usability engineering. Usability guru Jakob Nielsen says: “I advise clients to avoid design agencies that are too arrogant to include user testing in their project plans.” For that matter, if you are a user: do some quick and dirty usability testing to document on how bad (or how good) your system is – either to demand a better system, or to demand that the vendor provide usability updates! Read the rest of this entry



This entry is part 5 of 12 in the series Medical Computing

In past articles, we discussed human-illiterate computers, and we discussed usability, memorability, learnability and Tognazzini’s Paradox: how  changing a single word can make big differences in usability. We also discussed design integrity, simplicity, abstraction, and discount usability testing. Now, we’ll talk about personas.

It seems to me that personas are a bit like Critical Incident Stress Debriefing (CISD). Both have generated a lot of heated discussion: does it work? And, despite solid evidence that definitively answers the question, heated discussion continues.

<Sideline>There is good evidence that CISD doesn’t work, but there is a large national network of people strongly committed to providing CISD sessions for victims of disaster. Now don’t get me wrongCritical Incident Stress Management (CISM), of which CISD is just one part, is important. Psychologically stressful incidents may result in acute stress reactions which, if unrecognized and untreated, can lead to full-blown post-traumatic stress disorder (PTSD). CISD, which is a group debriefing session, a limited one-time psychological intervention, is promoted as a way to control acute stress reactions and prevent PTSD. But it’s been conclusively shown that CISD sessions are at best useless and at worse harmful. I am medical director for a multistate search and rescue organization. As such, I have had to review the literature and make a medical direction decision that, despite the strong feelings of CISD teams, our organization should never participate in CISD group debriefing sessions. This not to say that CISM isn’t needed; it is. But the “management” should not include group debriefing. </Sideline>

The evidence shows that CISD does not work. But the evidence shows that personas do work. There is certainly an air of “Cooper-worship” in the literature on personas, which excites some opposition (and “Cooper-hate”), but the underlying engineering strategy of using personas is solidly established.

OK, so what is a “persona” and why should you care? Read the rest of this entry