Table 2

Description of measures

Screening criteria to establish eligibility at waiting room survey*
 Young pregnancyCalculated from year of birth and dichotomised into ‘<23’ vs ‘≥23 years’22
 Living with another adult‘Yes’ vs ‘no’
 Support in pregnancyAnyone supporting participant through pregnancy, for example, financially, emotionally or practically? (This could be a partner/husband, relative or friend) (yes/no)
 Smoking‘Yes’ vs ‘no’
 Global healthSingle 5-point item (‘poor’ to ‘excellent’) from the self-reported SF6,23 dichotomised into ‘poor/fair/good’ vs ‘very good/excellent’24
 Long-term illnessHealth problem or disability that limits daily activities (yes/no), drawn from the UK 2001 Census25
 Anxious moodMatthey 2-item Generic Mood Question, which has shown good correlation with longer, validated anxiety measures including the EPDS and the Hospital Anxiety Depression Scale26
 EducationHighest level of school completed, dichotomised into ‘<year 12’ vs ‘completed year 12’ reflecting completion of secondary level education in Australia
 IncomePerson in household who currently has paid work/earns an income (yes/no)
 Ever workedParticipant has ever had a job before (yes/no)
Primary outcomes collected at 2 years
 Regular meal timesSingle 5-point item (‘never’ to ‘always)’. Study designed based on Sleep Well Be Well Regular Bedtime item27
 Food choices12-item measure of food choices over past 24 hours, rated on a 3-point scale (not at all/once/more than once), drawn from LSAC28
 Regular bedtimeSingle 5-point item (‘never’ to ‘always’), adapted from the ‘Sleep Well Be Well’ study27
 Regular bed routineSingle 5-point item (‘never’ to ‘always’), drawn from the ‘Sleep Well Be Well’ study27
 Safety of the environmentItems assessing aspects of home safety, which are dichotomised into ‘safe’ vs ‘not safe’. Study designed based on Royal Children's Hospital Safety Centre and KidSafe checklists30 31
 Warm parenting6-item measure assessing parental warmth. Items rated on a 5-point scale (‘never/almost never’ to ‘always/almost always’), drawn from LSAC29
 Hostile parenting5-item measure assessing parental hostility. Items rated on a 10-point scale (‘not at all’ to ‘all of the time’), drawn from LSAC29
 Parent responsivity and the home learning environmentHOME:32 45-item measure comprised of observation and parent report, assessing the quality and quantity of stimulation and support available to a child in the home environment. Items dichotomised (‘not observed or reported’ vs ‘observed and/or reported’) and summed. Continuous total score ranging 0–45, with higher scores indicating a better home environment. 6 subscale scores: parental responsivity (11 items), acceptance of the child (8 items), organisation of the environment (6 items), learning materials (9 items), parental involvement (6 items), variety in experience (5 items)
Secondary outcomes at 2 years
 Child ever breast fedSingle item ‘yes’ vs ‘no’
 Duration of breast feedingAge in months at which breast feeding stopped
 Age started solidsAge in months
 Drink choices apart from milk/formulaChild regularly has drinks other than milk or formula ‘yes’ vs ‘no’; if yes, list of regular drink choices28
 Feeding problemSingle 4-point item report of child feeding problems, dichotomised into yes (moderate/severe) vs no (none/mild), study designed based on LSAC sleep problem item28
 Child ate breakfast todaySingle item ‘yes’ vs ‘no’, drawn from LSAC28
 Sleep problemsSingle 4-point item report of child sleep problems, dichotomised into yes (moderate/severe) vs no (none/mild), drawn from LSAC28
 Child–parent relationshipSingle 5-point item (‘poor’ to ‘excellent’), study designed based on the single global health item drawn from the self-reported SF6
 Parenting efficacy4-item parenting efficacy scale. Items rated on a 10-point scale (‘not at all how I feel’ to ‘exactly how I feel’) drawn from LSAC, and a single 5-point parenting efficacy item assessing mother's feelings about herself as a parent (‘not very good’ to ‘very good’) drawn from LSAC29
 Global healthSee description in Screening measures above
 Maternal mental healthDASS:33 21-item measure, rated on a 4-point scale (‘not at all’ to ‘most of the time’) assessing the negative emotional states of depression, anxiety and tension/stress. Three subscales (7 items each): depression, anxiety and stress scales
 Life satisfactionPersonal Well-being Index (International Well-being Group, 2013):34 single item assessing general life satisfaction, and 8 items assessing satisfaction with specific life domains, rated a 10-point scale (‘no satisfaction at all’ to ‘completely satisfied’)
 Locus of control3 items assessing mother's self-efficacy or locus of control, drawn from the UK Millennium Cohort35
 Maternal quality of lifeAQoL-8D:36 37 35-item measure assessing health-related quality of life. Provides a single overall utility-based quality of life measure, and 8 separately scored scales: independent living, happiness, mental health, coping, relationships, self-worth, pain, senses, which can be totalled into 2 super dimension scales: physical and psychosocial
 Smoking‘yes’ vs ‘no’
 Current educationMother currently undertaking study or training ‘yes’ vs ‘no’; if yes, type of qualification, drawn from LSAC.28
 Current employmentMother currently employed ‘yes’ vs ‘no’; if yes, type of employment and age of child when mother returned to work.
 Maternal stressHair cortisol as a measure of maternal stress response over the past 3 months. The hair sample is a minimum length of 3 cm, with the total density of the sample equating to approximately half a pencil's width (30–50 mg). Cortisol concentrations to be reported as a continuous measure38
 Child global healthSee description in Screening measures above, collected for child and parent
 Child stressHair cortisol, see description for maternal stress above
 Communication and symbolic behaviourCSBS:39 6 items from the CSBS Developmental Profile Infant/Toddler Checklist (item numbers 7, 8, 11, 13, 18, 24) selected to assess child communication, which have not shown a ceiling effect when assessed at child age 2 years in a population cohort of child language.40 Items rated on a 3-point scale (not yet/sometimes/often)
 Maternal–child interactionsDrawn from fine analysis of maternal–child video, identifying maternal responsive behaviours (eg, expansions, imitations, questions, labels, directives) that are associated with child language outcomes, adapted from the work by Levickis et al40
 Sibling mental health and behaviour25-item Strengths and Difficulties Questionnaire (4–10 years old version):41 42 assesses emotional and conduct behaviour, and total difficulties scores (higher scores indicate greater problem)
 Parental enablementModified Parent Enablement Index:43 6-item measure assessing parent enablement as a result of services provided by the child health nurse, rated on a 3-point scale (much better/better/same or less)
 Parent satisfactionModified Parent Satisfaction Questionnaire:44 45 10-item measure assessing parent satisfaction with services provided by the child health nurse, rated on a 5-point scale (‘strongly agree’ to ‘strongly disagree’)
  • *Eligible participants report 2 or more of the 10 risk factors identified by risk factor screening.

  • AQoL-8D, Assessment of Quality of Life-8D; CSBS, Communication and Behaviour Scales; DASS, Depression Anxiety and Stress Scales; EPDS, Edinburgh Postnatal Depression Scale; HOME, Home Observation for Measurement of the Environment; LSAC, Longitudinal Study of Australian Children; SF6, Short Form-6.