Inattention Errors at Work: Living With Small Mistakes in ADHD

I send an email and in the second I press the send button I see it: the attachment is wrong. Or I have mixed up the client's name with another brand from a previous thread. Or I have forgotten the zero at the end of a figure in a table.

I do not make these mistakes because I do not know things. I know the job, I know which attachment it should be, I know the right figure. It is just that at that moment my eyes pass over it and do not see.

Sometimes a person makes more mistakes in what they know than in what they do not know.

Each of these mistakes is small. But they add up somewhere: as a record of "careless" in the other person's eyes and "sloppy" in my own. In this article I want to look at where those small mistakes come from and how I catch them.

It has a cost

First I want to say that these mistakes are not unimportant, because the attitude of "small mistake, these things happen" is also a kind of denial.

In a study in a large manufacturing company in the US, employees with ADHD were found to have roughly a 4-5 percent drop in job performance, about 2.1 times the relative odds of sick leave and about 2 times the relative odds of a workplace accident or injury (Kessler et al., 2009). This study was done in a factory setting and does not directly measure small mistakes in desk jobs. But it shows that fluctuations in attention have real consequences in the workplace.

In my work these mistakes mostly appear as a loss of trust. One wrong figure in a strategy document can make people question everything else in the document that is right.

Attention comes in waves

One of the most consistently measured features of ADHD in the laboratory is the variability of reaction time. In the same simple task, fast in one trial, slow in the next, then fast again. A meta-analysis that combined 319 studies found that this variability was marked in children and adolescents with ADHD and moderately high in adults too (Kofler et al., 2013). In the glossary its name is reaction time variability.

The same meta-analysis has an honest note and I do not want to skip it: this variability is not specific to ADHD. Adolescents and adults with ADHD could not be distinguished in this respect from groups with other clinical diagnoses. So this finding is not "the signature of ADHD"; it is a fluctuation of attention seen in many conditions.

When I turn this to my own work, the picture becomes clear. I check ten files; in nine my attention is in place, in one it is absent for a second. And I cannot know which file that second will fall on.

An inattention error is not attention being absent altogether. It is attention not being there at exactly that moment.

The mind is somewhere else

The second mechanism is the mind wandering on its own. The review by Bozhilova and colleagues suggests that people with ADHD characteristically describe excessive and spontaneous mind wandering, and that this may be related to the brain's resting network not quieting down enough during a task (Bozhilova et al., 2018). In the glossary: mind wandering.

Routine jobs are the most suitable ground for this. When I am preparing an invoice for the hundredth time, my hands do the job and my mind wanders around the next project. Right then the date gets written wrong.

That is why my inattention errors come up most in easy jobs. A hard job already catches my attention. An easy job releases it. I covered the office-environment version of the same pattern in the article ADHD and the open office, and how the environment is set up in the article ADHD at work.

Seeing the mistake late

The third mechanism feels the most familiar to me: not noticing the mistake, as much as making it.

Normally, when a person makes a mistake, the brain produces a very fast "something is wrong" signal and the person slows down at the next step. The review by Shiels and Hawk suggests that in ADHD both the early detection of a mistake and its later evaluation can be weaker, and that this makes adjusting behavior harder. The authors also note that the findings are inconsistent, and that it is hard to speak with certainty especially about early detection (Shiels and Hawk, 2010).

That I see the mistake one second after pressing send may be related to this. The signal comes, but it comes late. In the glossary the general name for this is error monitoring.

I must state a limit here: all of these mechanisms were measured in laboratory tasks. I could not find a study that directly examines the inattention errors adults with ADHD make at work and the methods that reduce them. The suggestions below are approaches I derived from these mechanisms and from safety research in other fields.

Why "be more careful" does not work

For years I told myself "be more careful." It never worked.

The reason now seems very clear to me: a wave of attention cannot be corrected with willpower. I cannot choose where my attention will be in that second. If the signal for noticing a mistake comes late, wanting it more does not speed it up.

The approach that works is to force attention from outside at the point where the mistake will happen.

The power of a checklist

The most striking example on this subject comes from surgery. With a nineteen-item safety checklist applied in eight hospitals in different regions of the world, the death rate fell from 1.5 percent to 0.8 percent, and in-hospital complications from 11 percent to 7 percent (Haynes et al., 2009).

Surgeons are not careless people. But even the most experienced specialist can skip a routine step. A checklist stops relying on memory and attention and makes it obligatory to ask certain questions at a certain moment.

For someone with ADHD this logic is even more valuable. Let me state once more that this study has nothing to do with ADHD. But it shows that a check set up from outside can catch a mistake without depending on the person's attention.

My small systems

A list only for the expensive points. Putting a checklist on every job turns into not using lists at all for me. Instead I chose a few moments where a mistake is costly: before sending a proposal, before handing in a report, before issuing an invoice. For each there is a list of at most five items. For a proposal, for example: recipient's name, brand name, figures, attachment, date.

A wait before sending. In my email I turned on the setting that delays sending for a short while. That one-second "oh no" moment after pressing send now falls within a period in which I can take it back.

The attachment first, then the text. When writing an email, my first job is to add the attachment, then check the recipient, and finally write the text. The forgotten-attachment mistake is almost entirely about this order.

Reading figures in a different way. When checking a table, instead of reading from top to bottom with the same eye, I read the figures aloud or check them in a different order. The eye completes the familiar pattern; when the pattern changes, it sees the mistake.

Fresh eyes. I read an important document one last time the next morning. When I read it the same day, my eye reads the text in my mind instead of the text on the screen.

A mistake notebook. I write the inattention errors I make in a short list: what happened, in which job, at what time of day. After a few weeks patterns appear. My mistakes gather most at the end of the day and in routine jobs. This information let me move those jobs to other hours. While keeping the notebook I set one rule: when writing down a mistake I do not use a single adjective about myself. Instead of "I was careless again," "at the end of the day, tired, I entered the invoice date wrong." The adjective blames me; the detail shows me where to put a check.

Keep the checklist short. The longer a checklist is, the less it is used. Choose the single moment when a mistake is most costly, and for that moment write only the three mistakes you make most often. Once the list has taken hold, you can move on to a second moment.

A second pair of eyes. On a truly expensive document, I ask someone else for a short look when possible. I stopped seeing this as proof of my own shortcoming; in publishing there is an editor, in surgery a team, in accounting a second check. Seeing the mistakes in your own text is hard for everyone, because the eye reads what it wanted to write.

After making the mistake

There are times when I fail to catch the mistake. I have a routine for those too: say it short, early and together with the correction. "One figure in the file I just sent was wrong, I have attached the corrected version." No long apology, no self-humiliation.

I described the cost at work of the urge to hide small mistakes in the article the pressure to look flawless. I also covered the memory side behind mistakes in the working memory article.

I still send the wrong attachment. But I no longer tell myself "you're sloppy." I say "a check is missing here." The first sentence makes me smaller, the second gives me something to do.