▁for ▁Aud itory ▁Ver bal ▁Ther apy ▁and ▁concluded ▁that ▁while ▁it ▁was ▁not ▁possible ▁to ▁demonstrate ▁a ▁cause ▁and ▁effect ▁relationship ▁between ▁the ▁inter vention ▁and ▁the ▁outcome , ▁increasing ▁the ▁strength ▁of ▁evidence ▁for ▁out comes ▁was ▁vital . ▁In ▁ 2 0 1 0 , ▁D orn an ▁et ▁al . ▁published ▁a ▁longitud inal ▁study ▁comparing ▁the ▁out comes ▁of ▁ 2 9 ▁children ▁en rolled ▁on ▁an ▁AV ▁programme ▁with ▁age - match ed ▁controls . ▁They ▁found ▁AV ▁to ▁be ▁an ▁effective ▁inter vention . ▁ ▁First ▁Vo ice ▁( a ▁membership ▁body ▁which ▁represents ▁organis ations ▁that ▁provide ▁listening ▁and ▁spoken ▁language ▁ther apy ▁in ▁Australia ▁and ▁New ▁Zealand ) ▁published ▁a ▁study ▁in ▁February ▁ 2 0 1 5 ▁based ▁on ▁information ▁on ▁more ▁than ▁ 6 0 0 ▁children ▁with ▁hearing ▁loss . ▁When ▁listening ▁and ▁spoken ▁language ▁out comes ▁of ▁children ▁with ▁a ▁hearing ▁loss ▁were ▁compared ▁to ▁those ▁with ▁typical ▁hearing ▁most ▁children ▁att ending ▁AV T ▁had ▁‘ sc ores ▁within ▁or ▁above ▁the ▁average ▁range ▁for ▁typical ▁hearing ▁children ▁for ▁language ▁( 7 4 . 4 % - 7 5 . 6 % ), ▁voc ab ul ary ▁( 7 9 . 6 %) ▁and ▁speech ▁performance ▁( 7 1 . 5 %). ▁When ▁children ▁with ▁additional ▁dis abilities ▁were ▁removed ▁from ▁the ▁analysis , ▁the ▁number ▁of ▁children ▁within ▁or ▁above ▁the ▁average ▁range ▁for ▁typical ▁hearing ▁children ▁increased , ▁except ▁for ▁speech ▁performance ▁( language ▁performance = 7