A medical certificate or report from the treating GP is acceptable.  Exceptions to this rule are complex cases such as, but not limited to: psychiatric conditions, multiple injuries, sequelae conditions which are not the subject of streamlining policies, contribution by non-compensable injuries, claims with a long gap between date of injury or date of discharge or the last incapacity.  In these circumstances, payment may be commenced based on a medical certificate or report from the treating GP however, a report by the treating specialist should be sought for confirmation.  If there is no treating specialist then an independent specialist's opinion should be obtained.