It’s common to defend procrastination by claiming that the pressure of a looming deadline leads to better work. But procrastinators may need to find a new excuse, since a five-year study on procrastination suggests that the quality of work decreases when it is performed close to a deadline.

The study, carried out at Warwick Business School in the U.K., plotted the submission times of 777 students against the final grades they received. There was an inverse correlation, meaning that the work submitted earliest received the highest marks.

The research was performed by Dr. David Arnott and Dr. Scott Dacko, and presented at the European Marketing Academy conference.

Later Times, Lower Marks

Exactly how early the essays were submitted had only a minimal effect: Those who turned in their work two days in advance were not worse off than those who turned it in three days in advance.

But in the 24 hours before the submission deadline, a clear pattern emerged, with quality dropping as the deadline edged closer. Delaying, Arnott summarized in a press release, had a “serious and detrimental effect on performance.”

Those who submitted just before the cutoff received a grade 5% lower than those who submitted a day in advance. Depending on a school’s grading system, that translates into a half or whole letter grade.

Identifying Chronic Procrastinators

Arnott and Dacko looked at data from both first-year and third-year students, and found no discernable differences between the two groups. They say this meansthat those who procrastinate are likely to keep up the habit without intervention; more experienced students do not, it appears, teach themselves better time management.

The researchers pointed to this as an area for educators to take more responsibility in promoting time management skills and good study habits.

“We are failing some students,” Dacko said in the release. “The need to enhance students’ ability to organise themselves and self-regulate learning … is evident.”

Of course, lower grades aren’t the only downside linked to procrastination. Other studies have shown that procrastinators have higher stress levels, poorer health and less motivation to improve either condition.