Characteristics of the eight studies that evaluated low weight gain as a risk factor for ROP.

∧Exclusive of birthweight and gestational age at birth.

*

Online algorithm that calculates difference between expected “safe” weight gain and actual weight gain; an alarm occurs if the accumulated values exceed a limit.15,16.

**

Calculated probability of severe ROP based on risk score incorporating GA, BW, and weight gain rate (g/d).

***

[1000×((weight28-weight7)/weight7)/(28-7)] = g/kg/day.