I read this book because working in a pharmacy, I hoped that having an understanding of the psychological basis of error might be helpful in avoiding it.

The book starts with some history. In the early twentieth century Freud was pondering on apparent slips and “accidents” having a basis in the subconscious. I suppose according to Freud, if someone made a slip in dispensing medication it would be because they had some deep seated dislike of a patient, or harboured unconscious opinions about their treatment! Thankfully, other views from the early twentieth century have aged better. In 1905 Ernst Mach wrote that “knowledge and error flow from the same mental sources, only success can tell one from the other.” Mach is referring to the fact that certain helpful types of behaviour, can also cause problems. For example, people have the ability to learn skills which involve a high level of automatic facility, allowing musicians to play musical instruments, typists to type, drivers to drive cars – all without thinking about the mechanics of every string plucked, key pressed or gear changed. But this automatic facility, so useful in many situations, can be a liability when circumstances alter. Step from a manual car into an automatic and you can run into problems when your left foot wants to press a clutch that isn’t there. In a pharmacy, if you have dispensed hundreds of boxes of a medication in a particular strength, there is an opening for error when you come to dispense an unusual strength of that same medication.

I suppose an awareness of this kind of situation does potentially help guard against times when routine brings the possibility of diminished conscious control. But Human Error is not the book to go to if you want simple answers. First there are those bad outcomes arising from useful behaviour. Then there’s the sense that an error is rarely confined to one person. When things go wrong it is usually the result of lots of people making many decisions meeting varied circumstances, which finally lead down to the unfortunate individual who makes a blunder – the last piece in a malign jigsaw puzzle. Then there are the traps in all the means we employ to guard against error – automated systems leading to loss of skills in dealing with problems; or systems protected by layers of defence tending to soak up hidden deficiencies until there is a sudden failure. Oddly, I came away from this book with a greater acceptance of error, even in trying to find a way to avoid it. Error is inevitable, and if you make error a forbidden sin, then you can never discuss or learn from things going wrong.

It is perhaps ironic that Human Error is a highly academic book, which leaves nothing to chance in its numbered sections, sub sections and sub sub sections. It does not flow. Concepts have to be nailed down into endless acronyms, leaving me floundering amongst SLIMs, SLIs, THERPs, PSFs, PIFs and SUs. Even the name Three Mile Island gets turned into TMI. I did not enjoy wading through this academic acronym code. I can’t see any problem with calling Three Mile Island by that name as many times as required.

Nevertheless, if you can live with the style, and accept that you won’t find an easy prescription that will make you a more accurate, less error prone person, this is a very interesting book. I would recommend it to anyone working in a job where a small slip can have serious consequences; or to anyone making big decisions, where small, unintended consequences in those decisions can store up serious problems for the future.