Book of the month: Why we make mistakes by Joseph Hallinan

"Why we make mistakes" is another "light" read for this month following on from last month's "Set phasers on stun". Joseph T. Hallinan is a former writer for the Wall Street Journal and winner of the Pulitzer Prize. The Pulitzer Prize was for investigative reporting on medical malpractice in Indiana, USA, and so it seems apt that he has now written a book on mistakes.

Who's it for?

This book is written for a general audience and, as summer holidays draw to a close, could be squeezed into the last few days off, now that the kids have gone back to school. Hallinan covers a number of human factors terms and concepts such as hindsight bias (p. 5, p.65), different types of mistakes (p. 8), framing (p.92), anchoring (p. 103) and illusion of control (p.162). He also mentions some of the big names in human factors research such as Simons and Levin (p. 14), Kahnemann (p.93, p.206), Ericsson (p. 172) and Gaba (p. 192).

I haven't got time to read a whole book...

Read the introduction, chapter 1, chapter 5 and the conclusion. (For a description of these chapters see below)

What's good about this book?

Hallinan starts off well, stating:

"When something goes wrong the cause is overwhelmingly attributed to human error.... And once a human is blamed, the inquiry usually stops there. But it shouldn't - at least not if we want to eliminate the error."(p.2)

In the subsequent 13 chapters, he goes on to look at different causes of mistakes and offers advice on avoiding them.

The tabletop on the left is obviously narrower and longer...

In the first chapter, "We Look but Don't Always See," Hallinan refers to vision, perception and change blindness. The "door" study by Daniel Simons and Daniel Levin may be a useful example to use when discussing this aspect of human factors in a lecture or workshop. This chapter also uses the two tabletops image to show that even when we know that something is true we still cannot force ourselves to see the truth.

In this first chapter, Hallinan then goes on to provide us for another reason that radiologists miss dancing gorillas (and tumours). The less frequently something occurs, the more likely we are to miss it. Because tumours are infrequent radiologists tend to miss them (this is another argument for not requesting tests such as chest x-rays on the off chance that something may be picked up.) Baggage screeners fare little better for the same reason, as Hallinan states, in 2006 at "Los Angeles International Airport screeners missed 75 percent of bomb materials." A reassuring thought for the next time you're standing in line at the airport with your belt and boots in one hand and the other hand holding up your trousers.

The next chapter which has a decent shot at dealing with a human factors problem is chapter 5: "We Can Walk and Chew Gum - but Not Much Else". Hallinan explores the myth of multi-tasking and looks at task saturation, trying to do too many things at the same time. An interesting concept here is that we can walk and chew gum at the same time because neither of these tasks requires conscious thought. We can drive a car and have a conversation because (once we are proficient) driving the car no longer requires our undivided attention. This idea may be useful to present in a human factors workshop or talk; i.e. repeated practice of managing crises in a simulator will allow one to use less mental workload on the basics during a real crisis.

Would you work for this man?

A final concept which may prove of interest is that constant change at the top of an organisation may not be helpful to the organisation itself. Hallinan discusses Warren Buffett's company, Berkshire Hathaway, where none of the CEOs have voluntarily left for other jobs in its 42 year history (p. 160). Hallinan proposes that the CEOs stay in post long enough to receive feedback and learn from their mistakes. Might this have lessons for the NHS?

Hallinan's advice for making fewer mistakes is given in the conclusion and that is to "Think small". Unfortunately he doesn't then quite manage to explain what this means, but instead goes on to provide other, more useful, advice:

1. Calibrate yourself. Be honest when you consider decisions that you have made and what their effect has been. (We have a tendency to think we performed better than we actually did.)
2. Think negatively. By considering what can go wrong you can prepare for that eventuality.
3. Ask others for advice. A spouse, friend or colleague may provide insight into a problem.
4. Sleep. Fatigued people perform less well.
5. Be happy. Happy people make decisions more quickly and are more creative with their problem-solving.

What's not so good about this book?

Areas which could be improved include Hallinan's introduction to System 1 and System 2 thinking which is somewhat clumsy, quoting Paul Slovic: "Our perception of risk lives largely in our feelings, so most of the time we're operating on system No. 1" (p. 95) He also digresses somewhat to spend a significant number of pages discussing the direction sense of men and women (p. 143-148).

Additionally Hallinan shows a slight lack of experience when he discusses how time affects decisions, stating:

"Many factors can affect the way we frame our decisions. One of the least obvious is time."

Anybody who has worked in a simulator or in an environment where time is critical, will be aware of how great an effect time has on on decision-making. Hallinan also mentions looking for "the" root cause which Sidney Dekker would have something to say about, namely:

"Asking what is the cause (of an accident), is just as bizarre as asking what is the cause of not having an accident. Accidents have their basis in the real complexity of the system, not their apparent simplicity. (p. xiii)" (The Field Guide to Understanding Human Error"

A final criticism of Hallinan's book (and perhaps much of human factors research) is that so many of the conclusions are based on research carried out on American university (Princeton, Ohio Wesleyan, Duke, Carnegie Mellon, Yale...) students; are these truly representative of the rest of the population?

To conclude

This is another book which should be borrowed, not bought. It has some material that may be useful for those who prepare human factors workshops. For the human factors novice it provides an easy-to-read introduction to some of the concepts and big thinkers in the field.

Putting patient safety first

Is your hospital adopting a safety culture? For both patients and staff? Below is a message sent to all hospital staff by the Interim Medical Director at Forth Valley Royal Hospital, Larbert. This is the sort of message we need to receive and spread in order to promote safety.

Dear Colleague

I am grateful to all of you who contribute to teaching and supervision of junior doctors and I am sure I can count on your wholehearted welcome and support to new colleagues starting this week.

Following recent guidance from the GMC and NES all new doctors at induction are being reminded of their duty to raise any concerns regarding patient safety as soon as possible.   This should be done as soon as possible after the perceived safety risk  -  with their supervisor or with another consultant in the department; with the Director of Medical Education (Dr David McQueen);  an AMD or;  with the Medical Director.   Concerns should be raised timeously in the knowledge that they will be considered seriously, without prejudice and will be acted upon appropriately.

The learning environment we provide should ensure that their training should take place in a supportive environment where undermining or bullying behaviour is not tolerated.   There is a ‘zero tolerance’ of undermining and we hope this will not be experienced at any time.   If the trainee feels that this is an issue for them, they are asked to urgently report it to a member of the consultant staff (if possible, to their clinical or educational supervisor or to a College Tutor, or equivalent).

Thank you again for your invaluable support.

Sent on behalf of

Dr Peter Murdoch

Interim Medical Director  

Forth Valley Royal Hospital

What's in a word?

The words we use allow us to think and talk about concrete things (such as cars) and abstract concepts (such as love). Although it depends on the definition of the word "word", today there are either 600,000 or over 1 million words in the English language, with the number of words increasing at the rate of 8500 per year. Depending upon education and literacy, a person will know between 35,000 to 75,000 words.

Language shapes our world

The language we use helps us to communicate with one another. Even more than that, the language we use both affects and reflects how we see the world. This is called "linguistic relativity". To show how language affects how we see the world we need only think about terms such as "global warming" and "credit crunch". These concepts express previously unknown dangers which affect how secure we feel about our own and our children's futures.

"Piegnartoq”: the snow [that is] good for driving sled

Language also reflects the importance we attach to certain ideas or things. For example, the Inuits have more than 50 distinct words for snow, reflecting the importance of this substance in their culture. (Although there is controversy regarding the exact number of words.)

The exclusion of particular words in a language system also implies a framework of values to the language users. When a behavioural marking system such as Anaesthesia Non-Technical Skills (ANTS) lists the behaviours expected of a good anaesthetist, these are endowed with added importance and those behaviours not listed may be considered to be less important. The idea that our language limits and determines our ability to think is called "linguistic determinism".

As an example of how language may affect thinking, let us imagine two new words: 

• Sladen
• Quaden

Sladen means the leadership required by a person in charge of strategy and long-term effects. Quaden is the leadership required when decisions are needed immediately with little or no information. One could use these terms to discuss a given individual's strengths and weaknesses, or to compare the characteristics of those who have one or the other type of leadership. The use of these new words would affect how we think about leadership. The words would also reflect our thinking, in the sense that we are interested enough in leadership for us to want to discern different types. (I'm using Sladen and Quaden as fictitious examples and am aware that terms such as "strategic leadership" already exist.)

The language of human factors

The language of human factors allows us to be more precise about what went well and what we found to be a challenge. If you have a teaching role then the human factors vocabulary will allow you to move from: "Well, that was terrible, wasn't it?" to "Your main problem was that you lost situational awareness when you volunteered to take over chest compressions." Learning the human factors vocabulary and concepts will also allow you to reflect both more effectively  and more efficiently on your own performance. For example, in the language of human factors, errors may be divided  into slips/trips, lapses, mistakes and violations. These types of errors have different causes and therefore different remedies. But without the vocabulary, a mistake is a mistake is a mistake; your ability to  improve yourself and others will be compromised.

Spreading the word(s)

Many religions have missionaries who "spread the Word". Although I don't equate patient safety or human factors with a religion, I would suggest that one of the activities that those of us involved in these fields should be doing is "spreading the word(s)". Jürgen Habermas reasoned that all speech acts have a goal, ie. by talking we are trying to have an effect on the world around us. The goal for us in the patient safety arena should be a wider understanding of the words and concepts which define human factors. With this vocabulary, the rest of the healthcare community and the people we care for will be better able to reflect, understand and discuss our failings and successes. Without this vocabulary we will be less able to improve the care we provide. Let us help transform the healthcare system so that when we talk about "hindsight bias", "power gradient" and "task fixation" every HCA, every nurse, every chief executive knows what we mean.

Book of the month: Set phasers on stun by Steven Casey

The subtitle of Dr. Steven Casey's book explains its appearance on this blog:

This book is an easy holiday read which does not tax the mind. The chapters, wich consist of 18 stories of human-technology/design problems, are independent of one another and can therefore be read out of sequence. As a reminder that human error and human-technology interface problems can be found wherever the two come into contact, this book suits both the general reader and the human factors devotee. 

Casey is the president of Ergonomic Systems Design, Inc. and an associate editor of "Ergonomics in Design" a publication of the Human Factors and Ergonomics Society (HFES). He read psychology and engineering at the University of California and North Carolina State University.

Published in 1993, Casey's book preceded the Institute of Medicine's landmark report "To Err is Human" by six years. In many ways this is a book which presaged the current interest in human factors in Medicine. This book focuses on the "incompatibilities between the way things are designed and the way people perceive, think, and act." 

Casey provides eighteen stories which he hopes will teach "a lesson about people, about the design of things, and about the necessity of addressing this all-important component of technology." The stories are well-written and engrossing, however there is very little exploration of human factors or human error. Do not, therefore, expect an expansion of your human factors vocabulary or theoretical constructs. 

Every story, except one, quotes a number of references to back up the dialogue and sequence of events. The story lacking references "Double Vision" (p.152-160) does not explain why these are lacking, although the suggestion from the author's prologue is that these events were witnessed by one of the protagonists. This person must then have relayed the story to Casey.

A potential use of this book may be to present one of the stories to an audience and ask them what human factors are illustrated therein. This may be of particular use if you have already covered the dancing gorilla and the "battleship vs lighthouse" scenario. For example, the chapter "A Memento of Your Service" tells the story of Pastrengo Rugiati, a captain of an oil tanker who has a deadline for docking at the oil terminal. If he fails to meet the deadline he will have to wait another six days before he can make another attempt. His ship has drifted off course, there are fishing boats in the area and he is taking a route he has never sailed before. This is the sort of complex, dynamic, stressful situation which we often encounter in healthcare and the parallels may be drawn by a human factors audience.

The book also illustrates the value of in situ simulation for stress testing. In the chapter "Return from Salyut" Russian cosmonauts have to close a valve on their spacecraft as it re-enters the atmosphere. Unfortunately the amount of time it takes to close the valve exceeds the amount of time available before the cabin depressurises. In situ simulation allows the healthcare community to test for these design failures in both equipment and processes.

At times Casey illustrates some of the characteristics which are perhaps frowned upon in human factors. For example in the above oil tanker story, Casey talks about the two fishing boats Rugiati has to worry about:

Actually, these were two French "crabbers" working the shallow waters of the shoals. This alone should have alerted the supertanker crew of the danger ahead. (p.52)

The subtext is that the crew should have recognised the fishing boats as "crabbers" but there is no indication as to how likely this is. On p.147 Casey talks about the "inevitable" shift of sea water within the Herald of Free Enterprise, a term that Sidney Dekker frowns upon. Dekker would argue that the word "inevitable" reflects old-school thinking about human error, where a sequence of events leads to an inevitable conclusion.

Although Casey's thesis is the need to be aware of the role of ergonomics in human error, the word "ergonomics" is never used and the argument is not developed. Many of the current concepts and vocabulary in human factors, such as situation awareness, shared mental model, task fixation, etc. are never mentioned. It is possible that this is because the book was written in 1993, however an introduction to the vocabulary of ergonomics would have been a useful addition for the novice reader.

A couple of additional complaints are:

• The size of the footnotes. At times these take up half the page (p.51) and it is often unclear why these footnotes are not embodied within the text.
• The lack of diagrams/illustrations. For example, on p.121-122 Casey uses a considerable number of words to explain the structure of an SL-1 reactor and on p.170-171 he describes the routes of a number of warships off the California coast. In both instances, simple diagrams would have been helpful.

Although wary of making this into a good news/bad news/good news "sandwich", none of the above criticism should stop you from borrowing (not buying) this book. The stories are interesting, from a wide range of industries and will provide you with additional fodder for your human factors workshops/talks.