Table 2.

Overview of constructs and assessments throughout the randomized controlled pilot study protocol

Construct	Measurement	Description	Intervals assessed	Reference
Primary outcomes
Feasibility of study		Number of eligible participants, randomized participants, retention and attrition of randomized participants	Baseline, mid-pregnancy, post-program, 3-month postpartum	[65]
Acceptability of IPT		IPT session attendance (≥ 80%), above-average participant IPT program ratings	Post-program	[66]
Secondary Outcomes
Social functioning	SAS-SR	24-item self-report scale of interpersonal functioning in family, friend, romantic, and school or work domains	Baseline, mid-pregnancy, post-program, 3-month postpartum	[67]
	NRI-BSV	28-item self-report scale of relationship characteristics for mother, father, peer, and romantic partner relationships		[68]
Perceived stress	PSS	14-item self-report scale to assess perception of stress	Baseline, mid-pregnancy, post-program, 3-month postpartum	[69]
Depression	CES-D	20-item self-report scale to assess depression symptoms	Baseline, mid-pregnancy, post-program, 3-month postpartum	[70]
	EPDS	10-item self-report scale to assess depression symptoms	Baseline, mid-pregnancy, post-program, 3-month postpartum	[71, 72]
	MINI-KID	Structured clinical interview to assess psychiatric disorders, such as major depressive disorder	Baseline, post-program, 3-month postpartum	[73]
Disinhibited eating	EDE	Semi-structured interview to assess disordered eating including objective binge, subjective binge, and objective overeating	Baseline, post-program, 3-month postpartum	[74, 75]
	EES-C	25-item self-report questionnaire to assess eating in response to negative emotions	Baseline, mid-pregnancy, post-program, 3-month postpartum	[76]
Physical activity	ActiGraph GT3X+	Body-worn accelerometer to measure 7 days and nights of habitual physical activity including step counts, light and moderate-vigorous intensity, and sedentary time	Baseline, mid-pregnancy, post-program	[77, 78]
Sleep disturbance	ActiGraph GT3X+	Body-worn accelerometer to measure 7 nights of sleep including total sleep time, sleep onset latency, wake after sleep onset, and sleep efficiency	Baseline, mid-pregnancy, post-program	[79, 80]
Body composition	BMI indices	Height and weight measured to calculate BMI	Baseline, mid-pregnancy, post-program, 3-month postpartum	[81]
Maternal postpartum adiposity	Body fat	DXA conducted to measure body composition including total fat and lean mass	3-month postpartum	[82, 83]
Maternal insulin sensitivity	WBISI, QUICKI, HOMAIR	7-sample, 2-h oral glucose tolerance test to estimate insulin sensitivity	3-month postpartum	[84, 85]
Infant adiposity	Body fat	Infant PeaPod conducted to measure body composition including total fat and lean mass	3-month postpartum	[86]

Baseline baseline/screening assessment occurring around 12–18 weeks gestation; Mid-Pregnancy mid-pregnancy assessment occurring around 21–28 weeks gestation; Post-Program post-program assessment occurring around 30–34 weeks gestation; 3 Month Postpartum assessment occurring around postpartum week 12; SAS-SR Social Adjustment Scale, Self-Report; NRI-BSV Network of Relationships Inventory-Behavioral Systems Version; PSS Perceived Stress Scale; CES-D Center for Epidemiologic Studies-Depression Scale; EPDS Edinburgh Postnatal Depression Scale; MINI-KID Mini-International Neuropsychiatric Interview for Children and Adolescents; EDE Eating Disorder Examination; EES-C Emotional Eating Scale-Adapted for Children; BMI body mass index (kg/m², z-score, percentile); DXA dual-energy X-ray absorptiometry; WBISI whole body insulin sensitivity index; QUICKI quantitative insulin sensitivity check index; HOMAIR homeostasis model assessment of insulin resistance