Email Interruptus

Chances are, you won’t get to the end of this story without being interrupted by a text message or an urgent email that you just have to open. And I’m okay with that; I just checked my email in the middle of writing this first paragraph.

According to some studies, the average knowledge worker enjoys a measly five minutes of uninterrupted time; once interrupted, half won’t even get back to what they were doing in the first place. Yet organizational expectations or social pressures make it hard to resist the urge to check incoming emails or text messages — pressing tasks be damned.

Most of us harbour some shame at our inability to ignore interruptions from our technological tools. Shamel Addas understands your pain but says these interruptions are not necessarily bad. They can even be productive.

“I know from personal experience that some interruptions are actually good,” says Addas, an assistant professor of information systems at Smith School of Business. “It depends on the content and timing. You can get some critical information that will help, like completing your task. So that’s one of the assumptions I feel needs to be challenged and tested.”

While interruptions are widespread, Addas says, our understanding of how they influence individual performance is limited. What we do know is based on lab studies of discrete events that last a few seconds, which is not how interruptions play out in the working world.

“What happens in real life is more like a continuous stream of interruptions, like a chain of interruptions, and we often don’t go back to the interrupted task right away,” says Addas. “Sometimes each interruption in and of itself is not that bad but the effect can accumulate over time and lead to fatigue and stress. So it’s important to understand the bad and good effects of interruptions over time and as they accumulate.”

Hybrid Interruptions

Addas has conducted several studies to pry open “the black box of the relationship between interruptions and performance.” His first study was based on interviews with software and product developers at eight information technology firms. He started with the idea that not all interruptions have the same effects, and divided them into system-generated interruptions, such as system crashes or buggy software, and those mediated by technology, such as emails or text messages.

Addas also looked at the content of the interruptions, and distinguished between those that were “congruent” and “incongruent.” Congruent interruptions contain relevant and key information, reveal potential problems, or request actions that relate to an employee’s primary activities. Incongruent interruptions provide or request information or actions that aren’t relevant to primary activities. They may relate to non-core work or be personal in nature.

Among other things, Addas identified “hybrid interruptions”; they don’t fit with the current task but do fit within the broader meaning of a person’s work. “These hybrid interruptions have mixed kind of effects,” says Addas. “They cost you in terms of time and possibly output quality because they disrupt what you’re working on, but they compensate for these effects because they help people understand what they’re doing in the broader picture. These interruptions can come in handy for future tasks or projects.”

The Good in Email Interruptions

In his second study, Addas focused on email interruptions. He gleaned data from a survey of 365 business-to-business salespeople and a web-based diary that 212 B2B salespeople used to record interruptions over several days.

He was particularly interested in understanding the impact of interruptions not only on the task at hand but on related core tasks, such as prospecting customers, preparing for sales calls, making presentations, or closing the sale. He therefore focused on individuals’ overall exposure to interruptions over the course of their work.

Just recognizing that there are different types of interruptions, each with its own trade off, can help managers mitigate the negative impacts on performance and stress

What the study showed is that the interruptions that were incongruent to primary activities directly undermined the workers’ performance — they led to higher error rates, poorer memory, and lower output quality. It also took longer for the salespeople to return to their primary work and complete their tasks. Incongruent interruptions also had an indirect effect on performance: they increased workers’ stress levels by making them feel their workload was unmanageable.

That was expected. While congruent interruptions — those that contribute to workers’ primary activities — also increased stress levels, they also boosted salesperson performance. They were tied to mindful processing of task activities, which led to better performance both in terms of efficiency and effectiveness.

Out of Sight, Out of Mind

Addas also discovered that the very features of the interrupting technology can influence the outcomes of the interruptions positively or negatively. Individuals who engaged in several email threads of conversations at the same time or those who kept getting interrupted by email but let the messages pile up in their in-box experienced higher stress levels and lower performance.

“This creates a constant reminder of all the stuff that needs to be done,” says Addas. “On the other hand, for those who just deleted emails or filed them into other folders, it was out of sight, out of mind.

And those who reprocessed their received messages during interruptions episodes or rehearsed their message responses before sending saw some benefits. Doing this enabled them to process their tasks more mindfully, Addas says, which boosted their performance.

Addas says that technology-based interruptions can have effects on group performance as well.  The stress that individuals feel, for example, can spill over to close colleagues. And when there are interdependencies on tasks, if one person is constantly interrupted, others must pick up the slack.

Management Implications

What does this mean for managers? For one thing, just recognizing that there are different types of interruptions, each with its own trade off, can help managers mitigate the negative impacts on performance and stress.

Addas suggests that managers develop email management programs and interventions, such as specifying a time-response window for emails based on their urgency or relevance to primary activities. They can also establish periods of quiet time for uninterrupted work. And they can encourage work groups to develop effective coordination strategies to ensure one person’s interruptions do not adversely affect colleagues.

As for individuals, they can start handling interruptions in batch rather than in real time to reduce the costs of switching back and forth between tasks and interruptions. To reduce stress from overload, Addas suggests, people should limit parallel exchanges during interruptions and delete or folder messages that are of limited use for their core work.

“People might well consider thinking carefully about the messages they construct and examining carefully their previously received messages as needed to ensure that they process their tasks more mindfully, which is beneficial for performance,” Addas says.

Addas believes there are design implications to consider as well, particularly relating to context aware systems and email clients. Context aware systems know what kinds of tasks people are working on and can detect high and low periods of workload. “Email clients can be programmed to screen messages for task-relevant content and distinguish between incongruent and congruent interruptions,” he says. “They can then manipulate the timing at which each type of interruption is displayed to users, such as masking incongruent interruptions until a later time.”

After all, even the most disciplined of us need a little help to resist temptation.

— Alan Morantz

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