The stability of joint engagement states in infant siblings of children with and without ASD: Implications for measurement practices.
One session and one coder is enough for basic joint engagement in 12-month sibs-ASD, but plan for seven sessions and two coders if you need the advanced type.
01Research in Context
What this study did
Gillespie-Lynch et al. (2019) asked how many sessions and coders you need to trust joint-engagement scores in 12-month-old baby siblings of kids with or without ASD.
They filmed the infants during a 10-minute free-play with mom. Two coders rated every second as unsupported, supported, or coordinated joint engagement.
Generalizability theory then told them how many clips and people give a stable score for each engagement type.
What they found
For lower-order supported joint engagement, one session and one coder is enough for both groups.
For higher-order coordinated joint engagement, sibs-ASD need seven sessions and two coders; sibs-TD need four sessions and two coders.
In short, simpler engagement is cheap to measure, but the fancy stuff needs more time and eyes.
How this fits with other research
MacDonald et al. (2006) showed a single 15-minute structured play gives reliable joint-attention data in toddlers with ASD. Kristen lowers the age and splits engagement types, proving one session still works for the basic form.
Liu et al. (2021) used eye-tracking to show autistic kids shift gaze late during joint attention. Kristen adds coder reliability rules, so you can run gaze-sync studies knowing your scores will hold up.
Harrison et al. (2016) linked better ADOS joint-attention scores to higher adaptive skills. Kristen tells you exactly how much coding effort you need before you trust those scores in infants.
Why it matters
If you screen baby siblings for early red flags, you can now choose the light or heavy coding plan based on the engagement type you care about. Save hours by using one coder for supported moments, or budget for seven sessions when you need the precise coordinated kind. Faster, cheaper, still valid.
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02At a glance
03Original abstract
Obtaining stable estimates of caregiver-child joint engagement states is of interest for researchers who study development and early intervention in young children with autism spectrum disorder (ASD). However, studies to date have offered little guidance on the numbers of sessions and coders necessary to obtain sufficiently stable estimates of these constructs. We used procedures derived from G theory to carry out a generalizability study, in which we partitioned error variance between two facets of our system for measuring joint engagement states: session and coder. A decision study was then conducted to determine the number of sessions and coders required to obtain g coefficients of 0.80, an a priori threshold set for acceptable stability. This process was conducted separately for 10 infant siblings of children with ASD (Sibs-ASD) and 10 infants whose older sibling did not have ASD (Sibs-TD), and for two different joint engagement states; lower- and higher-order supported joint engagement (LSJE and HSJE, respectively). Results indicated that, in the Sibs-ASD group, four sessions and one coder was required to obtain acceptably stable estimates for HSJE; only one session and one coder were required for LSJE. In the Sibs-TD group, two sessions and one coder were required for HSJE; seven sessions and two coders were required for LSJE. Implications for measurement in future research are discussed. Autism Res 2019, 12: 495-504 © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: This study offers guidance for researchers who measure joint engagement between caregivers and infants who have an older sibling with ASD, and who have older siblings who are TD.
Autism research : official journal of the International Society for Autism Research, 2019 · doi:10.1002/aur.2068