Is it necessary for a PhD candidate to publish at least 3 journal articles before oral defense?
It depends on university to university, some universities have this requirement, however for some just oral defense is also enough......i have seen where university don't have requirement, thesis advisor have requirement of papers and even they mention the I.F of journal for securing papers....
Sometimes, it is good to encourage doctoral students to publish but not to stipulate an arbitrary requirement. Otherwise, quality will suffer. In my opinion, one good paper in a quality journal/conference is better than 3 papers written to satisfy a requirement.
I strongly agree and maybe more than 3. That what happened with me during my MSc (4 WoS papers) and PhD (7 WoS papers). This is what i follow with my students.
In University of Lagos, Nigeria, a minimum of ONE publication in peer reviewed journals (university based or academic society journals) is a precondition for PhD oral defense.