Stability of Vocal Variables Measured During the Early Communication Indicator for Children With Autism Spectrum Disorder.

The team asked: how many 6-minute Early Communication Indicator (ECI) sessions do we need to get a steady picture of a toddler’s vocal skills?

They watched toddlers with autism during brief play samples and tracked when the child babbled, said words, or made other sounds.

The goal was to see if two or three short clips give the same numbers as longer testing.

Two or three 6-minute play samples were enough. The vocal scores stayed the same across sessions.

This means you can trust quick ECI probes to track early talking skills without long testing days.

Bak et al. (2019) looked at minimally verbal school-age kids for a whole school year and saw no growth in sounds or adult chats. The difference is age: toddlers are just starting to talk, while older, minimally verbal children may need targeted language teaching to move forward.

Ohan et al. (2015) followed toddlers with autism up to age 9 and found big gains in language for many. McDaniel et al. (2021) shows we can spot those early vocal signs quickly, giving us a clear starting point for the long run.

Mason et al. (2025) found that toddlers who already mand, play with sounds, and copy motor actions are more likely to echo words. Pair their checklist with a short ECI probe: if the child shows the green-light skills and ECI numbers are steady, you’re ready to start echoic training.

You now have a fast, reliable way to measure early vocal skills. Use 2–3 six-minute ECI samples to set a baseline, then watch for the echoic green lights Mason et al. (2025) describe. If the child isn’t moving forward after several probes, add focused language intervention instead of waiting—Bak et al. (2019) shows spontaneous growth is unlikely in older, minimally verbal children.