Confidence in Pope Francis' handling of his church's global sex abuse crisis has plummeted among US Catholics, according to a new Pew Research Center poll.

Just three in 10 Catholic adults say he is doing an 'excellent' or 'good' job addressing the issue, down 24 points since 2015 and 14 points from when Pew Research Center last asked the question in January of this year.

While seven in 10 American Catholics say their overall opinion of Pope Francis is favorable, six in 10 now say he is doing an 'only fair' or 'poor' job handling the sex abuse scandal, including 36 per cent who say his efforts on this front have been poor.

The decline in confidence in Francis' handling of the crisis is consistent across different Catholic groups. For instance, since 2015 it has declined by 24 points among Catholic men and 23 points among Catholic women.

Even among Catholics who say they attend mass weekly, the share who give Francis positive marks for his handling of the sex abuse crisis has been cut in half since 2015; 34 per cent in this group now give Francis 'excellent' or 'good' ratings for his handling of the issue, whereas 67 per cent gave him a positive evaluation in 2015.

US Catholics' overall opinion of Pope Francis remains favourable at around 70 per cent. However, this is down 12 points since the beginning of the year. Only 30 per cent now say they have a 'very favourable' opinion of him.

Among the US public as a whole – including both Catholics and non-Catholics – roughly half say they have a favorable view of Pope Francis, which is the lowest rating he has received in nine Pew Research Center surveys that have asked about Pope Francis since the beginning of his pontificate in 2013.