I had been thinking about writing a post about this for some time, then serendipitously, this tweet came up in my timeline:

@AlonKeinan @jrossibarra papers have 4.5 auths on average and get 2.6 reviews, so you only need to do 0.6 reviews for each sub you’re on

— Axios Review (@AxiosReview) October 9, 2013

Well I’ve got something to say about that, but we’ll get to that shortly.

I want to start with a gripe – as academic/associate editor at FrontiersIn and BMC (and formerly PLOS ONE), I often find it really difficult to find reviewers for papers. I’d say around 50% of the time, an invite is sent and is simply ignored – not accepted, not declined, just left to expire. I’m not sure on what planet this is an acceptable “response” to a peer review invitation, but it’s not on my planet. If you can’t do it, click “decline to review” – it really helps and prompts editors to invite someone else. Ignorance is just rude. I’m keeping a list by the way, things will go far better for you if you stay off my list 😉

Now, let’s get to @AxiosReviews’ flawed tweet. According to the US Library of Medicine, it looks like the average paper has 5 authors, not too different to the tweet above’s claim of 4.5. The number of peer reviews is intuitively between 2 and 3, so 2.6 seems a decent estimate too – though there is no mention of the editor, who is often simply an academic donating some of their time to the journal, just like a peer reviewer.

The fatal flaw of the tweet above is the maths – the number of authors / number of reviews leading to 0.6 reviews for every paper you’re on. This assumes all authors are equal, and of course they are not. Editors look at prior publications to select reviewers and are simply not going to choose someone from the middle of a list of authors; so the effective number of authors per paper is 2 – the first author and the last author.

If we then accept 2.6 as the average number of reviewers, and add in the editor, we get 3.6.

The maths now looks quite different – for every first or last author paper you publish, you need to complete 1.8 reviews – almost double.

But wait – this is still wrong. This assumes each paper is only reviewed once, clearly untrue for papers that are rejected by certain journals before eventually being accepted, and those papers that are reviewed but never published (for the purposes of simplicity I am counting multiple rounds of review of the same paper at the same journal is one unit of peer review).

Rejection rates are hard to come by, but this article suggests that 25% of papers go first to a journal different to the one they eventually get published in. So we need 25% more input from editors and reviewers, and our 3.6 turns into 4.5.

Where we end up is that, for every first or last author paper you publish, you need to carry out 2.25 editorial or peer review activities.

We return to my question – for every first or last author paper you need to carry out at least two editorial or peer review activities – are you in peer review debt or credit?