Table 1.

Assessment Instruments and Assessment Schedule

	Assessment Time Point (month)
Child Measures
Growth Measurements: Weight (gm), Height (in), Head Circumference (cm) (See Table 2 for an explanation of the transformation of these outcomes for purposes of analysis.)	3, 6, 12, 24, 36
Bayley Scale of Infant Toddler Development III (BSI-III):²⁵ The BSI-III provides an extremely thorough, standardized assessment of infant development. In the present paper we report Cognitive, Language, Motor, Social-Emotional, and Adaptive Behavior scores. The composite scores are norm-referenced and standardized with a mean of 100 and a standard deviation of 15.	6, 12, 24, 36
Receptive-Expressive Emergent Language (REEL)-3:²⁶ The REEL-3 is a 66-item, norm-referenced test administered to caregivers, developed to identify young children who have developmental problems in use or understanding of language. It is composed of two subtests, for emerging receptive and expressive language skills. The present paper reports on the Receptive and Expressive Ability scores and percentile ranks, and the Language Ability scores. The three Ability scores are scored according to population norms, in a manner similar to intelligence tests, with means of 100 and standard deviations of 15.	12, 24, 36
Infant Toddler Sensory Profile (ITSP):²⁷ A standardized instrument for assessing a child’s sensory processing abilities and to profile the effect of sensory processing on functional performance in daily life. There are 36 items for children 0–6 months, and 48 items for children 7–36 months. There are four quadrants: Low Registration (13 items for 0–6 month form; 11 items for 7–36 month form), Sensation Seeking (6; 14), Sensory Sensitivity (12; 11), and Sensation Avoiding (5; 12), and a Low Threshold score representing a sum of the Sensory Sensitivity and Sensation Avoiding quadrant scores. Quadrant scores are computed by summing the responses to each item on a 5-point scale, ranging from 1 (“Almost always”) to 5 (“Almost never”), so that lower scores indicate relatively more functional problems in a given area of sensory processing.	3, 6, 12, 24, 36
Infant Behavior Questionnaire Revised (IBQ-R):^28,29 A 91-item inventory of infant behavior in 14 domains: Activity Level; Distress to Limitations; Fear; Duration of Orienting; Smiling and Laughter; High Intensity Pleasure; Low Intensity Pleasure; Soothability; Falling Reactivity/Rate of Recovery from Distress; Cuddliness; Perceptual Sensitivity; Sadness; Approach; and Vocal Reactivity. Respondents score the frequency of infant behavior on a scale of 1 (“Never”) – 7 (“Always”). Scores on each domain are the mean of the item ratings in that domain, so in some cases, higher scores indicate more of a negative behavior (eg, Fear) while in other cases, higher scores indicate more of a positive behavior (eg, Cuddliness).	3, 6, 12
Maternal Measures
Parenting Stress Index (PSI):³⁰ A 120-item inventory of parental stress in three domains: Child, with 6 subscales (Distractibility/Hyperactivity, Adaptability, Reinforces Parent, Demandingness, Mood, and Acceptability) that measures sources of stress from child behavior, as reported by the parent; Parent, with 7 subscales (Competence, Isolation, Attachment, Health, Role Restriction, Depression, and Spouse/Parenting Partner Relationship) that measure sources of stress related to parent functioning; and a Life Stress scale that measures the amount of parent stress caused by situational factors other than from the child or parent. The Child and Parent domains combine to yield the Total Stress scale. The 101 Child and Parent items are each scored on a 5-point scale (1 “Strongly Agree” – 5 “Strongly Disagree”), with the 19 Life Stress item responses indicating whether the events have occurred (0 “No” 1 “Yes:) in the past 12 months. Higher scores for each subscale and the two domain scores and the total score reflect more stress in that area.	3, 6, 12, 24, 36
Infant Toddler Home Observation for Measurement of the Environment (ITHOME):³¹ A 45-item inventory measuring 6 domains of the home environment important to child development: Responsivity (11 items) Acceptance (8), Organization (6), Learning Materials (9), Involvement (6), and Variety (5). Each domain has a separate score ranging from 0 to the number of items in the respective scale; the domain scores are then added to yield a Total Score (range: 0–45), with higher scores indicating a relatively more enriched home environment.	6, 24, 36
Addiction Severity Index (ASI):³² A clinical assessment of addiction severity that measures functioning in 7 areas of the respondent’s life: Medical, Employment, Drug, Alcohol, Legal, Family/Social, and Psychiatric. Items from each section are weighted and contribute to a composite score for each area, with scores ranging from 0–1, with higher scores indicating greater problem severity.	3, 6, 12, 24, 36