Are there any independent, widely-accepted codes of conducts or guides for when authorship should be given on a paper? Would be helpful to have these to refer to to avoid potential confusion or conflict over attribution.
Or is this more a matter for individual institutions and academics to decide?
NB my field is economics.
An internet search for "requirements of authorship" will turn up the information you need. I point specifically to the stamens of ICMJE, which gives a good summary applicable outside the medical field as well.
Not all fields adhere closely to this, though it requires interpretation. In some lab sciences in which a PI runs and finances a lab, hires lab assistants, etc. it is often the case that the PI appears as an author even when having little to do specifically with the work other than to provide the environment in which that work was possible. Doctoral students, for example, can't fund their own multi-million dollar labs. But even in these cases, the PI probably vets the work (directly or indirectly) and is expected to stand behind all claims and results.
But, do the search to see how widely these ideas are shared. A number of research universities publish similar statements as you will see.
