The number of clock hours (where the circumferential extent of the disease is described in segments as if the top of the eye were 12 on the face of a clock) affected by Retinopathy of Prematurity as determined during Retinopathy of Prematurity Screening.

This attribute is also known by these names:

Context	Alias
plural	RETINOPATHY OF PREMATURITY CLOCK HOURS MAXIMUM STAGES