The major gaps in data on abuse among children in state and faith-based institutions has a chilling impact for some.
An interim report by the Royal Commission estimated up to a quarter of a million young people have been abused in care.
But a data specialist says the state's failure to record data properly - including the ethnicity of those in its care - means it's almost impossible to know the scale and impact of the harm.
Te Aniwa Hurihanganui reports.