It is becoming increasingly important to keep track of performance, do scientists have a good figure of merit to measure their performance?
There is no single measurable criteria by which one can easily evaluate the researcher performance.
Some quasi-efficient metrics include:
- publications - but it is relatively easy to produce a large number of low-quality papers (salami slicing, guest authorship, incremental research, unnecessary duplication of studies, paid-for publications, etc)
- publications in top-quality journals - better, but leads to massive bias towards well-funded groups and neglects good research from low-funded countries, individuals and research areas. Some very excellent researchers may decide not to go through peer-review system and publish their results only on preprint platforms like arXiv
- publications and citations (e.g. h-index) - better, but can be manipulated through excessive publishing and self-citations
There are other metrics, but none is perfect. Generally speaking, research is about the study of unknown, and you can't put a good KPI for this sort of activity, because you can't reliably measure what you don't know.
The h-index is the most common metric, but as this article shows, it can have counterintuitive behavior. Therefore, there is no good KPI for scientific careers.