According to one of those often-quoted statistics that should be true but probably isn’t, the average number of people who read a PhD thesis all the way through is 1.6. And that includes the author. More interesting might be the average number of PhD theses that the typical scientist — and reader of Nature — has read from start to finish. Would it reach even that (probably apocryphal) benchmark? What we know for sure is that the reading material keeps on coming, with tens of thousands of new theses typed up each year.

To what end? Reading back over a thesis can be like opening up a teenage diary: a painful reminder of a younger, more naive self. The prose is often rough and rambling, the analyses spotted with errors, the methods soundly eclipsed by modern ones. And students in the process of writing a thesis can find themselves in a very dark place indeed: lost in information, overwhelmed by literature, stuck for the next sentence, seduced by procrastination and wondering why on earth they signed up to this torture at all.

Two News Features this week reflect on that question. They examine the past, present and future of the PhD thesis and the oral examination that often accompanies it. In one, three leading scientists — including Francis Collins, director of the US National Institutes of Health — dig out and reread their theses for us, and talk about what they learned. Their musings (filmed and available in a series of videos) show, reassuringly, that they are just the same as the rest of us. They made mistakes, had moments of self-doubt and considered quitting. (Collins actually did quit.) But their stories also reveal how it is important to have the long view in mind.

Thumbing through their theses now, they see how much they learned about the scientific process and how to conduct rigorous research. They realize how precious it was to be able to devote themselves to a single piece of original and creative work. And they feel a sense of accomplishment and pride — as everyone tends to after any difficult life challenge that they struggle with and eventually conquer.

“Students could do themselves and their audience a favour by keeping it crisp and short.”

Completing a thesis represents a coming of age not just scientifically, but also educationally and personally. It signals the passing of an intellectual milestone — from a student under the care of a supervisor to an individual who asks questions of their own. It marks the end of formal education, and graduation to a new phase in life. For many people, it also sees their departure from science altogether. Often, the PhD years coincide with significant personal events, as we mature emotionally and meet friends, partners and colleagues who will stay with us for life. All this can also turn thesis-writing into a more significant event than merely the writing up of a (usually) minor piece of science.

Still, it’s perhaps too easy to get sentimental over the thesis. For a start, the process has to keep up with the times. The PhD is already assessed in many different ways around the world (as the second News Feature describes) and scientists should welcome ways to keep it relevant. The goal of PhD assessment everywhere remains, rightly, to demonstrate that a student has conducted, and can communicate, independent, original research. But the way in which that’s achieved can and should be improved.

For one thing, it doesn’t have to involve a vast printed volume. A lot of students could do themselves, their supervisors, their examiners and their wider audience a favour by keeping it crisp and short. Postgraduate supervisors should stress this at the beginning. And it’s important to make the work in the thesis available to future researchers by publishing or sharing the data in some form. To contribute to the world beyond the author’s immediate circle, a PhD thesis should be read and used, and not just serve as a shelf ornament or doorstop.

For those inspired to go back to their own thesis, and those who are examining a freshly written one, it’s best to be kind. As long as the fundamentals are there — the question is interesting and the approach and analysis rigorous — it’s fair to forgive the typos and the research paths that turned out to be dead ends. A PhD is, after all, training in research, and to try — and fail — is a valuable part of that course.

Do you know where your PhD thesis is? Dig it out and share with @NatureNews on Twitter using the hashtag #3wordthesis. You might even bump up that average readership.