Scope of PhD in General Practices for a Psychologist?

[Farhan2017]

Dear All Greetings, I hope everybody doing very well, My wife has M.Phil Applied Psychology (18 years qualification with Thesis) she got opportunity to do PhD in General Practices, As it does not 100% relate to her educational background but have some relevancy specifically she can do research in Psychology and produce thesis but her degree will be awarded in General Practices which is more related to Medical Research and education, My Question is should we go for this PhD opportunity or look for anything more related to Psychology??