Table 2

Criteria for disability: established methods

Northern criteria		Victorian criteria		Mersey criteria
Severe disability	Cerebral palsy severe enough to hamper age appropriate activity	Severe disability	Cerebral palsy—unlikely to walk	Severe disability	For example:
	Deafness warranting a hearing aid		Bilateral blindness		Spastic quadriplegia
	Blindness or partial sight		Developmental index 3SD or more below the mean		Blindness
	Developmental quotient <70				Deafness
	Epilepsy uncontrolled by drugs				Epilepsy—uncontrolled
	Permanent stoma				Developmental quotient <50
					Multiple disabilities

Impairment without disability	Mild cerebral palsy	Moderate disability	Cerebral palsy—non-ambulant but likely to walk	Moderate disability	For example:
	Developmental quotient 70–79		Sensorineural deafness requiring amplification		Spastic diplegia or hemiplegia
					Developmental quotient 50–69

Minor impairment	Squint	Mild disability	Cerebral palsy—ambulant	Mild disability	For example:
	Growth retardation after bowel resection		Developmental index between 1SD and 2SD below the mean		Myopia, language delay, mild hearing loss, hyperactivity, motor clumsiness
	Speech delay with hearing loss

Normal	None of the above	Normal	None of the above	Normal	None of the above