A lab journal (also called a lab notebook) is a central piece in proper scientific working. However, it is likely that many students graduate from university without having a working approach to how to maintain a lab journal. On the other side, many supervisors do not discuss about journaling with their mentees until it is too late and bad habits have already formed.
Part of the problem is that lab journals during the studies are meant to be used for a semester at most, while professional lab journals are to be used during years or even decades.
Aging PI's don't help, since they normally stop maintaining journals when they stop working in the lab, and they may end up with antiquated practices and without knowledge of the tools current students are being exposed to on a daily basis.
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