Different ways I thought of:
- Looking at the size of the potential PhD advisor's lab: e.g., if many (>10) PhD students or post-doc, then likely to be quite hands-off.
- Asking current or former members of the potential PhD advisor's lab. (but sometimes it is difficult to establish contact with them and obtain a frank answer, plus that's a bit tedious to do for each potential PhD advisor's lab).
- Directly asking the potential PhD advisor but I am unsure whether this is a wise approach as for example if the prospective PhD student is asking the potential PhD advisor whether they are hands-on or hands-off, this could be construed as being too much dependent or independent from the PhD advisor (e.g., a hands-off PhD advisor would typically prefer independent PhD students), which might reduce the chance of being accepted in the PhD program in case of mismatch between the PhD advisor and prospective PhD student.
What could be other techniques for a prospective PhD student assess whether a potential PhD advisor is hands-on or hands-off, preferably without impacting that chance is to be accepted in the PhD program?