What is the author's style in Blood Relations by Sharon Pollock?

The roots of documentary theatre go back to 1925 and the work of Erwin Piscator According to Robert C. Nunn in Canadian Literature, this approach "forgoes the traditional emphasis of dramatic theatre on the timelessness of the human condition in favour of an emphasis on the human situation unfolding in a specific historical context." It's an attempt to get at the truth that can be hidden by the existence of fact.