Dilemma: Not allowed to use race as a reference to groups

I am sitting with a dilemma. How do you refer to groups without making reference to race?

Let me explain.  I am doing research on the transfer of learning and have found that there are the same tendency in certain areas.  The areas that I am referring to is

AREA 1:                Cape Town, Rondebosch, Mowbray, Plumstead

AREA 2: Mitchells Plain, Hanover Park, Athlone

AREA 3: Kayelitsha, Gugulethu, Langa, Nyanga.

I am not allowed to refer to a, for example,  ‘traditionally coloured area’, because then I am referring to race.  I am also not allowed to use the terminology ‘previously disadvantaged areas’ and ‘previously more disadvantaged areas’.

I will appreciate any recommendations.