publications - How long should it take to read a paper?

I am wondering how long it usually takes to read a research article. I can see that the answer depends on:

• The knowledge and intelligence of the reader


• The field of research


• The journal



• The individual paper

So I am particularly interested in how long a PhD student or a young post-doc would take to get through a molecular or systems biology paper published in journals like Nature, Science, Cell, PLoS and PNAS. We can focus on papers of typical complexity for the journal, and ignore those that are exceptionally easy to read or exceptionally complex.

On multiple occasions I have been able to skim an 8 page, 5 figure paper in as little as 10-15 minutes. From this I could glean enough information to follow and even participate in a class or journal club discussion (though there would be a lot of asking question like "how exactly did they do this/explain this in the paper? I didn't read very carefully").

However, when a paper is very important (for example I want to use a variation of their methods for my own project) I feel the need to read it much more carefully. It seems worthwhile to closely look at even very trivial things, such as description of standard procedures like cell culture in the methods, exactly how much of each chemical was used for simple, routine reactions, close examination of control experiments from the supplement, what papers the paper has referenced to justify their work, and even what commercial systems were used and from which company, and whether the paper actually followed the protocol in the manual and so on. After putting this much effort, I also feel like I should take notes. This produces a heavily highlighted and annotated paper plus about 4 pages of notes.

All of this takes a lot of time. Occasionally it could take me a few days to work my way through a very important paper (for instance, if their method is unfamiliar to me and I will be adapting it for my own research, or if I want to draw conclusions by reanalyzing their data).

My question is, is this typical? How long do you usually take to read a paper? Should I start putting effort into teaching myself to read faster, or should I just accept it and make time by scheduling other activities to accomodate paper reading?

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I can imagine an "incremental" strategy for reading at arbitrary depth. For instance, you could read the paper several times, each time reading more carefully, like so:

1. Read only the title, parts of the abstract, and look at the pictures.


2. Read abstract more carefully, look at title headingfs of results section.


3. Quickly skim the results section to look for main point of the paper.


4. Scan introduction and discussion, read results carefully to understand obvious limitations of their conclusions.


5. Carefully read all sections, including methodology, to make a comprehensive list of all assumptions made and all potential issues with the research.


6. Carefully go through all supplements, look at raw data if any and consult the other papers cited as justification to contextualize the research.

Logically, I see the merit of something like this, but I haven't tried it for the "dense" readings I've talked about above. The reason is that I'm not sure how I can take notes effectively when I do something like the above. It may also be harder to motivate myself to re-read a paper I've already skimmed, because I've given away the punchline to myself and the novelty factor is gone.

I've also written an answer on Mathematics@SE, which I think might be relevant to this question.

Note that I am not asking how to read a paper. This has been addressed in several previous questions already. I am only asking how long it should take a typical junior scientist to read one, so I can benchmark myself and see if I am slower or faster than is usual.