. Author manuscript; available in PMC: 2014 Feb 1.

Published in final edited form as: Am J Speech Lang Pathol. 2012 Jul 30;22(1):25–39. doi: 10.1044/1058-0360(2012/11-0145)

Table 5. Estimated percentages of gesturing (i.e., non-zero) subpopulations from ZIP model.

	9-12 months			15-18 months

Gesture Type	AU	DD	TD	AU	DD	TD
SI	35%	58%	66%	46%	68%	75%
SI	(n≈14.0)	(n≈13.3)	(n≈23.1)	(n≈12.4)	(n≈10.9)	(n≈12.0)
BR	38%	53%	62%	52%	67%	74%
BR	(n≈15.2)	(n≈12.2)	(n≈21.7)	(n≈14.0)	(n≈10.7)	(n≈11.8)
JA	13%	43%	58%	45%	81%	89%
JA	(n≈5.2)	(n≈9.9)	(n≈20.3)	(n≈12.2)	(n≈13.0)	(n≈14.2)

Key: SI = Social Interaction; BR = Behavior Regulation; JA = Joint Attention

Note: The ZIP model estimates to number of participants in a given sub-population, and therefore the estimates do not translate to actual numbers of participants, but theoretical numbers of participants. The theoretical numbers of participants in the gesturing subpopulations are estimated in the parenthetical statements below the estimated percentages. These are the numbers that were utilized for all analyses conducted with the ZIP model.