Hi the pages on talkingpoint.org.uk will help -
EYMP 5 the
free resource page is also good reading.
Factors to consider when seeing how speech & language can vary betweeen children at enrolement ..
Age and stage of development
The amount of stimulation and encouragement they have received
Child's first language or language that's spoken at home
Individual speech, language, communication needs or particular difficulties
National and local policy -
ECaT guidance
Hth