Effect of early childhood development interventions implemented by primary care providers commencing in the neonatal period to improve cognitive outcomes in children aged 0–23 months: protocol for a systematic review and meta-analysis

Over 40% of disadvantaged children under 5 years globally have neurodevelopmental problems resulting in deficits in social, emotional and educational functioning into adulthood [1‐3]. Early childhood development (ECD) interventions delivered to children aged under 5 years have been clearly shown to have substantial and sustained impacts on long-term cognition and neurodevelopmental outcomes [4‐6] ECD interventions have also been shown to improve maternal mental health outcomes [7, 8]. ECD interventions are defined by the World Health Organization (WHO) as physical, socioemotional, cognitive and motor development interventions implemented between birth and 8 years of age [9].

The importance of the family and social environment in influencing children’s neurodevelopment is well known [10, 11]. However, the impact of health services, especially primary care, is less well understood. Primary care providers include community health workers, generalist nurses, health visitors, midwives, child health nurses and general practitioners. Primary care providers are the first level of health service provision and provide a range of comprehensive community and clinical services. Recent demographic and health surveys indicate that primary care staff provide over 90% of health care for families during the first 5 years of life [12]. Primary care providers are in a unique position to augment early child developmental outcomes prior to school entry [13, 14]. Primary care staff routinely provide health advice, counselling and the promotion of behaviour change for their clients. Pregnant women, families and caregivers of young children receive anticipatory guidance, health promotion, health education, promotional interviewing and motivational interviewing. They also receive screening, surveillance and ‘brief interventions’. Delivery channels include home visiting, mobile health teams, clinic visits, group programmes, telehealth, postnatal care and child health checks [13, 14]. However, many primary care providers lack skills and confidence in developmental care for young children and few receive appropriate training, education and tools.

These observations led to the development of the WHO/UNICEF ‘Care for Child Development’ package (CCD). CCD is focused on improving the skills of health care providers in counselling families about responsive caregiving and stimulation for their children [15, 16]. There has been one large robust evaluation of the effect of CCD delivered by primary care providers. In Pakistan, a large randomised controlled trial (RCT) of CCD delivered by female primary care health workers to families of children aged less than 24 months followed up 1302 children to 4 years of age [17, 18]. Children who received responsive stimulation had significantly higher cognition (effect size [Cohen’s d] 0.1 for IQ, mean difference from control 1.2, 95%CI 0.3–2.7), executive functioning (0.3 [0.18, 0.07–0.29]) and prosocial behaviours (0.2 [0.08, 0.03–0.13]) at 4 years than children who did not receive responsive stimulation. Mother’s responsive caregiving behaviours were also higher in the intervention than the control group (0.3 [1.95, 0.75 to 3.15]) at 4-year follow up. Other primary care provider ECD interventions include video feedback, positive parenting, family partnership working, attachment-based interventions and motivational interviewing [19‐23]. Four systematic reviews report the important impacts of ECD care packages delivered by primary care providers to families of children under 5 years on child and adult cognitive outcomes [24‐27].

Simple interventions implemented by primary care providers in the neonatal period (0–27 days) such as early initiation of exclusive breastfeeding, skin to skin contact and handwashing have been shown to substantially reduce mortality and morbidity in children under 5 years [4, 28, 29]. Globally, there is increasing recognition of the importance of the ‘golden’ minutes, hours and days after birth for infant health and development [30‐32]. Knowledge about the effects of ‘neonatal ECD’ interventions, such as responsive stimulation focused on play and communication, is also increasing [6, 15]. There is also clear evidence that the nervous system undergoes major shifts in myelination during the neonatal period, and there is great plasticity especially within the cortical and limbic systems [33]. There are a growing body of data to show that neonates are not simply reflexive and subcortical but have important communication and social behaviours especially eye contact, visual locking, auditory responses, responsiveness and self-quietening behaviour [33‐35]. By the end of the first month of life, neonates respond to language, look at bright contrasts, movement and colour. Healthy neonates regulate their physiological states by self-soothing, habituate to repeated sensory inputs and respond to social speech [36, 37]. However, to our knowledge, there has been only one systematic review of the effect of ECD interventions commencing the neonatal period [36]. This review included 16 RCTs of 851 participants and assessed the impact of two specialised tools (the neonatal behavioural assessment scale (NBAS) and neonatal behavioural observation (NBO) tool). Seven studies involving 304 participants contributed data to one meta-analysis of the impact of these tools on caregiver-infant interaction, and the results suggested a significant, medium-sized difference between intervention and control groups (SMD − 0.53, 95%CI − 0.90 to − 0.17), but no other outcomes were reported in the included studies or the systematic review [36]. There appears to have been no systematic review or meta-analysis of the effect of ECD interventions in the neonatal period delivered by primary care providers.

Our overall aim is to conduct a systematic review of the effect of ECD interventions implemented by primary care providers commencing in the neonatal period. Our primary objective is to assess the effects on cognitive outcomes in children aged 0–23 months. Secondary objectives are to assess effects on (1) other childhood neurodevelopmental domains (speech, language, fine motor, gross motor, social, emotional, behaviour) at 0–23 months and (2) maternal mental health outcomes.

We will also assess effects by (1) type of health care provider (i.e. primary care provider vs other), (2) timing of the neonatal contacts with health care providers (i.e. interventions delivered in the first hour, first day, first week and first month of life), (3) timing of any antenatal interventions, and (4) ‘dose’, i.e. number of contacts with health care providers in the neonatal or antenatal periods.

We also will assess effects in subgroups: (1) premature or low-birth weight infants and (2) other highly disadvantaged infants such as those born to mothers with substance use disorders, mental health disorders, mothers living with domestic violence and mothers subjected to other forms of violence such as armed conflict and refugees and (iii) type of primary care provider (community health worker, nurse, doctor, other).

We will also assess effects in specific country and population level strata such as low-income countries and high-income countries, African countries and Asian countries, fragile and conflict-affected countries, countries with restricted levels of female empowerment, and indigenous populations.

Frequently cited benefit-cost ratios from the USA suggest that for every dollar invested in ECD services, there will be at least a $2 return to society [44, 45]. The economic return has been estimated at between 15 and 17% for every dollar taking into account crime, education and welfare savings, and increased taxes due to higher earnings [44, 45]. Interventions implemented in the neonatal period are likely to be even more cost-effective because primary care providers have many potential contacts with mothers and infants throughout the first month of life ranging from birth attendance to postnatal care and early immunisation services [12, 46]. Primary care coverage is high in the early days after birth, even in low-income countries and disadvantaged populations, but then ‘drops out’ with estimates ranging from 80–100% coverage in the early neonatal period to 10–20% by the third month of life [12].

Despite these data, there is little evidence about the effectiveness of current primary care service models in improving quality of neurodevelopmental care in the neonatal period from 0–27 days of life. There has been little opportunity to rigorously test new primary care service models that could improve newborn health outcomes, especially the most disadvantaged children. In this complex population health environment, many research, academic and funding organisations have lost sight of the importance of developing simple tools for upskilling of primary care providers in the earliest months of life. Neonatal care is especially medicalised. Information about ECD interventions delivered by nurses, midwives, community health workers and front-line ‘on the ground’ workers, and simple interventions and support is particularly needed.

The findings of our review will be an important resource for policymakers, primary care providers and researchers in a variety of different settings. Our review will provide data about which studies, if any, have assessed the effects of ECD implemented by primary care providers commencing in the neonatal period. We will provide up to date information of impact on childhood cognitive outcomes in children aged 0–23 months, any longer-term cognitive effects and effects on maternal mental health outcomes. We will also assess effects by timing of postnatal and antenatal contact and dose response. Our study will assist in understanding the impacts of neonatal ECD interventions on premature and low-birth weight infants and other disadvantaged populations.

Our next steps will include the development of clinical trials to fill gaps in knowledge about the effectiveness and cost-effectiveness of neonatal ECD in high-, middle- and low-income settings and to understand the resources required for implementation at scale.