Table 2.

Relevant Codes and Descriptions from the Home Observation Coding System

Code	Description
Activities (State)	Coded throughout videos
Activities of Daily Living	eating, bathing, dressing, grooming, food preparation, household chores (e.g., included activities such as a parent vacuuming near child)
Social Activities	social activities with another person; other person must be actively engaged for social purposes (i.e., not merely helping child engage in an otherwise solitary activity)
Free Play	any play or leisure activities not otherwise described, including play with equipment (e.g., trampoline, swings)
Behaviors (State/Point)	Coded when behaviors occurred, lasting at least 5 seconds
Hyperresponsive	child demonstrates negative or exaggerated response to stimulus or actively avoids stimulus
Hyporesponsive	child does not react/respond to stimulus in their environment within 5 seconds
Sensory Seeking	child engages and seems particularly interested in activities that provide intense, unusual, or prolonged sensory input (other than those listed under repetitive/stereotypic below)
Repetitive/Stereotypic	child engages in 5 seconds or 3 repetitions of specific unusual behaviors (i.e., rocking, flapping, lining up toys, object flicking, and repeating phrases or video segments)
Sensory Modality† (Point)	Used as descriptors of coded sensory & repetitive behaviors
Tactile	behavior clearly related to sensation of touch/texture on skin
Auditory	behavior clearly related to sounds perceived by ears
Gustatory	behavior clearly related to food/oral stimuli
Olfactory	behavior clearly related to scents perceived by nose
Visual	behavior clearly related to perception through the eyes
Vestibular/Proprioceptive	behavior clearly related to sensation of body movement
Stimulus Characteristic (Point)	Used as descriptors of coded sensory & repetitive behaviors
Novel or Familiar	whether stimulus was new or previously-known to child
Child- or Family-Initiated	whether child chose to engage or was directed/introduced to stimulus by family/other person
Social or Nonsocial	whether stimulus itself was social in nature (distinct from social activity)

Notes. State codes measure duration; Point codes identify events as they occur.

^†, Multiple modalities could be coded for a single behavior; however, gustatory code was used solely to capture all food/oral stimuli and other related modalities (e.g., tactile, olfactory) were not coded concurrently in these instances.