Low doc loans are the source of most of the increase in arrears on home loans, at least among those loans funded through securitisation.A quarterly review by Moody's Investors Service shows the arrears rate on low doc loans climbed quickly this year to reach 3.9 per cent at September 2008 and up from around two per cent a year ago. Moody's reports arrears of 30 days or more.On pools of prime home loans, arrears climbed to around 1.3 per cent at September 2008, up from around one per cent a year earlier but scarcely any worse than in December 2006.