The latest Newshub-Reid Research poll shows Prime Minister Bill English's credibility has taken a hit over the Todd Barclay scandal.

It comes as questions remain over Mr English's involvement, and why he sent more than 450 texts to the women at the centre of the scandal - Glenys Dickson.

Fifty-six percent of voters lost some trust in Mr English over the scandal. Thirty-five percent of voters didn't lose trust in Mr English, while 9 percent didn't know.