Description of study measures by cohort
| Mother-only measures | ||||||
| Type of measure/ name of instrument | Instrument details | Data relating to | Hypothesis type (primary, secondary) and label (a, b, c…) | |||
| Healthy mother modification | Session one (infant aged 9 months±1 month) | Session two (infant aged 12 months±1 month) | Session three (infant aged 18 months±1 month) | |||
| Background and sociodemographic information | Questions about the mother’s demographic background (age, ethnicity, social class, income, partner status) and previous parenting experience | 5a–5b removed | X | 3a | ||
| Obstetric history | Questions about the mother’s pregnancy and birth in relation to the infant involved in the current study | n/a | X | 3a | ||
| Medical history | Questions about the mother’s physical health | n/a | X | 3a | ||
| Substance use | Questions about the mother’s use of alcohol, cigarettes and drugs. Some items can be taken from/supplemented by medical records if consent is given | n/a | X | 3a | ||
| Psychiatric history | Questions relating to the mother’s psychiatric history. Some items can be taken from/supplemented by medical records if consent is given | All questions removed | X | 2a, 2b, 3a | ||
| Brief Psychiatric Rating Scale (BPRS) | This is a 24-item measure that assesses positive, negative and affective symptoms among people with a mental illness. The 24 items include somatic concern, anxiety, emotional withdrawal, depressive mood, hostility, blunted affect, excitement and disorientation. The BPRS is scored by summing the items, with scores ranging from 18 to 126; a higher score is indicative of more severe symptomatology.53 | All questions removed | X | 3a | ||
| Hospital Anxiety and Depression Scale (HADS) | This is a 14-item measure that assesses anxiety and depression in a general population of both patients and the general population.54–56 There are seven items relating to anxiety, and seven relating to depression. Items are rated on a 4-point Likert scale with 0 representing the least symptomatology and 3 representing the highest; there are six reverse scored items in total. The HADS is scored by summing the items relating to anxiety and depression separately, for both scales a score of 7 or less indicates feelings are in the normal range. | n/a | X | 3a | ||
| General Health Questionnaire-12 | This is designed to screen for non-psychotic and minor psychiatric disorders, comprising two sections: (1) ability to carry out normal functions and (2) appearance of distress.57 58 | n/a | X | 3a | ||
| The Postpartum Bonding Questionnaire | This is a 25-item self-administered measure designed to detect issues within mother–infant relationships.59 Items are rated on a 6-point scale with 0 representing the least cause for concern and 5 representing greater issues in the mother–infant bond. There are 15 reverse scored items. The 25 items encompass four subscales: (1) a general impairment scale (12 items, scores ranging from 0 to 60), (2) rejection and anger (7 items, scores ranging from 0 to 35), (3) anxiety concerning the infant (4 items, scores ranging from 0 to 20), and (4) developing risk of abuse (2 items, scores ranging from 0 to 10). Total scores are calculated by summing the 25 items (scores range from 0 to 125). Analysis of the scale includes both total and subscale scores.59 | n/a | X | 3a | ||
| Childhood Trauma Questionnaire (CTQ) | This is designed to assess adults and adolescents for a history of childhood trauma using a 28-item retrospective self-report questionnaire.60 This contains five subscales: (1) physical abuse, (2) sexual abuse, (3) emotional abuse, (4) physical neglect and (5) emotional neglect.60 Each subscale has five questions; the additional three questions are designed to detect individuals who may under-report their trauma. Items are rated on a 5-point scale with 1=’never true’ when they were growing up, to 5=’very often true’ when they were growing up. Thus, scores range from 5 to 25 for each of the abuse types. The CTQ has demonstrated reliability and validity in both patient and community populations.61 62 | n/a | X | 3a | ||
| EQ-5D-5L | This measures health-related quality of life across five dimensions (mobility, self-care, usual activities, pain/discomfort and anxiety/depression), each rated on five levels (no problems, slight problems, moderate problems, severe problems and extreme problems).63 The participant indicates their health state by ticking the box next to the most appropriate statement, and rates their health today on a scale of 0 (the worst health you can imagine) to 100 (the best health you can imagine). The scores from each of the dimensions are combined to form a unique health state from a possible 3125 combinations.63 | n/a | X | 3a | ||
| Composite Abuse Scale (CAS) | This is designed to measure partner abuse over the past year. The 30-item self-administered questionnaire is rated from 1=’never’ to 5=’daily’, with total scores ranging from 0 to 150. There are four dimensions within the scale: severe combined abuse, emotional abuse, physical abuse and harassment.64 The CAS has been validated for patient and community populations.64 65 | n/a | X | 3a | ||
| Infant medical notes and growth trajectories | Using information from the NHS-provided Personal Child Health Record (aka ‘the little red book’) to record data on infants APGAR scores and early weight measurements. | n/a | X | 3a | ||
| Qualitative questionnaire | Research team designed topic guide to be administered at the final (18-month) session. This consists of open-ended questions relating to the mothers’ experience of the study as a whole and in particular their understanding and feelings towards the fNIRS process. | n/a | X | |||
| Mother/iInfant measures | ||||||
| Manchester Assessment of Caregiver-Child Interaction | Mother–infant interactions are captured in a 6 min video clip taken during unstructured play.66 Coding of the interaction is completed by a trained rater and assesses two caregiver scales (sensitive responsiveness and non-directedness), four infant scales (attentiveness to caregiver, positive affect, negative affect and liveliness), and two dyadic scales (mutuality and intensity of engagement).66 This measure has been validated and used within both patient and community populations.67 68 | n/a | X | 3a | ||
| Bayley Scales of Infant and Toddler Development | Researcher-administered scales that examine motor (fine and gross), language (receptive and expressive) and cognitive development of infants and toddlers alongside their socioemotional and adaptive behaviour.69 These scales have been used to assess general development and as a test for neurodevelopmental delay across both western and non-western cohorts.70 71 The scales are flexible enough to use the subtests independently based on research question.69 | n/a | X | X | 1a | |
| fNIRS assessment | Design—based on published pilot25—created to capture changes in infant neural responses to vocal and non-vocal sounds across 9, 12 and 18 months. Infants listen to vocal and non-vocal sounds with different emotional valences while sitting on mum’s lap for a maximum of 15 min. The fNIRS equipment uses near infrared light to capture changes in blood oxygenation in response to the stimuli, which is analogous to brain function. This will be used to assess whether fNIRS can detect early biomarkers of language delay in high-risk children. | n/a | X | X | X | 1a, 2a, 2b |
fNIRS, functional near infrared spectroscopy; n/a, not applicable.