One way to better sort articles is based on Keywords (see my post on keywords).

However, there is another way I will shortly describe here.

There are a number of categories a research paper can belong to:

- Basic Research
- Theoretical Research (especially in Math/Physics)
- Trials:
  -- randomized controlled trial
  -- Meta-analysis
  -- other trial
- Review
- Guideline
- Correspondence
- Editorial
- Epidemiologic Study
- Case Report
- Images in clinical medicine (some Journals have such a feature/ could be a
subgroup of Case Report)
- Questions/ Question-Answers

If there are other relevant categories, feel free to implement them as well.

This is especially useful when searching for all trials on a given matter (e.g.
for writing a meta-analysis or writing a review or a guideline), or for a
specific case report.

I do have some >2500 of articles saved on my computer and searching for the
correct file is a nightmare. It may seem that 2500 articles is a huge number,
however in infections diseases this is only a minimum to start with.

It is useful to have a field storing this information. Although custom fields
exist, this is a feature that should be standard. It allows searching (and
grouping) articles on a more powerful basis.

I posted this request on the bibus site, too.
https://sourceforge.net/tracker/index.php?func=detail&aid=1504712&group_id=110943&atid=657833