Adaptation of the Mullen Scales of Early Learning for use among infants aged 5‐ to 24‐months in rural Gambia

Bosiljka Milosavljevic,Lamin Sanyang,Helen Maris,Clare Elwell,Saikou Drammeh,Momodou K Darboe,Sarah Lloyd‐Fox,Perijne Vellekoop,Drew Halliday,Sophie E Moore

doi:10.1111/desc.12808

Abstract

Infants in low‐resource settings are at heightened risk for compromised cognitive development due to a multitude of environmental insults in their surroundings. However, the onset of adverse outcomes and trajectory of cognitive development in these settings is not well understood. The aims of the present study were to adapt the Mullen Scales of Early Learning (MSEL) for use with infants in a rural area of The Gambia, to examine cognitive development in the first 24‐months of life and to assess the association between cognitive performance and physical growth. In Phase 1 of this study, the adapted MSEL was tested on 52 infants aged 9‐ to 24‐months (some of whom were tested longitudinally at two time points). Further optimization and training were undertaken and Phase 2 of the study was conducted, where the original measures were administered to 119 newly recruited infants aged 5‐ to 24‐months. Infant length, weight and head circumference were measured concurrently in both phases. Participants from both phases were split into age categories of 5–9 m (N = 32), 10–14 m (N = 92), 15–19 m (N = 53) and 20–24 m (N = 43) and performance was compared across age groups. From the ages of 10–14 m, Gambian infants obtained lower MSEL scores than US norms. Performance decreased with age and was lowest in the 20–24 m old group. Differential onsets of reduced performance were observed in the individual MSEL domains, with declines in visual perception and motor performance detected as early as at 10–14 months, while reduced language scores became evident after 15–19 months of age. Performance on the MSEL was significantly associated with measures of growth.

Highlights

The United Nations Sustainable Development Goals (UN, 2015) have identified the reduction of poor child development in low‐ and middle‐income countries (LMICs) as a key priority for global health research and interventions
The present study describes the outcomes of a series of pilot studies using the key cognitive development behavioural assessment of the Brain Imaging for Global Health (BRIGHT) study—the Mullen Scales of Early Learning (MSEL)
We aimed to test the following hypotheses: 1. Given prior findings that early life exposure to environmental risk is associated with reduced cognitive ability from an early age, and that performance worsens with age (e.g., Hamadani et al, 2014), we predict that our sample will exhibit reduced MSEL scores from the age of 5‐months

Summary

| INTRODUCTION

The United Nations Sustainable Development Goals (UN, 2015) have identified the reduction of poor child development in low‐ and middle‐income countries (LMICs) as a key priority for global health research and interventions. The current study preceded, and contributed to, the development of a large‐scale prospective longitudinal study underway in The Gambia to measure early brain and cognitive develop‐ ment across the first 2 years of life: The Brain Imaging for Global Health (BRIGHT) Study—www.globalfnirs.org/the-bright-project This project aims to implement brain imaging and neurocogni‐ tive developmental methods (including functional near infra‐red spectroscopy [fNIRS], electroencephalography [EEG] and MSEL) to model longitudinal changes in brain function and cognitive de‐ velopment, identify critical time points, and moderators and me‐ diators of compromised development within this rural Gambian population. These factors pose important threats to healthy development, which is reflected in the finding that a majority of the children in this setting exhibit moderately severe growth faltering from the age of 3‐months (van der Merwe et al, 2013)

| Aims and hypotheses

| Participants

| Procedure and optimization

Findings

| DISCUSSION