Night owls are more likely to underperform at work than those who are more productive in the morning, a new study suggests.

Researchers wanted to assess whether so-called evening chronotypes have poorer work ability than morning larks, or morning chronotypes, because of their ability to function during standard morning working hours.

They assessed almost 6,000 workers in Finland who are part of a life-long study.

When the study participants were aged 46, they were quizzed about their working life and health, and they were questioned about their sleep patterns to find out their natural chronotype.

Overall, 10% of men and 12% of women were deemed to be evening chronotypes and the majority of these (72%) worked in day jobs.

They were monitored over the next four years to see who had stopped working and taken a disability pension.

The findings, published in the journal Occupational & Environmental Medicine, suggest that night owls may be twice as likely as morning larks to underperform at work, according to their self-rated performance.

Around 28% of men and 24% of women classed as owls were considered as underperforming at work when they were 46, a significantly higher proportion than among larks or intermediate chronotypes.

The odds of underperformance were twice as high among the owls as they were among the larks.

Night owls were also more likely to have retired early due to disability, though these numbers were small.

“We found that evening chronotypes were associated with double-sized odds of poor work ability compared with morning chronotypes,” the authors from the University of Oulu in Finland wrote.

They suggested that a person’s chronotype should be considered “when planning work schedules”.