The impact of home-installed growth charts and small-quantity lipid-based nutrient supplements (SQ-LNS) on child growth in Zambia: a four-arm parallel open-label cluster randomised controlled trial.

Background: Childhood stunting remains common in many low-income settings and is associated with increased morbidity and mortality, as well as impaired child development.

Methods: The main objective of the study was to assess whether home-installed growth charts as well as small-quantity lipid-based nutrient supplements (SQ-LNS) can reduce growth faltering among infants. All caregivers of infants between 2 and 10 months of age at baseline, and at least 6 months old at the beginning of the interventions, in 282 randomly selected enumeration areas in Choma, Mansa and Lusaka districts in Zambia were invited to participate in the study. Cluster randomisation was stratified by district. A software-generated random number draw was used to assign clusters to one of four arms: (1) no intervention (control); (2) home installation of a wall chart that contained a growth monitoring tool along with key messages on infant and young child feeding and nutrition (growth charts only); (3) 30 sachets of SQ-LNS delivered each month (SQ-LNS only) or (4) growth charts+SQ LNS. The primary outcomes were children's height-for-age z-score (HAZ) and stunting (HAZ <-2) after 18 months of intervention. Secondary outcomes were haemoglobin (Hb), anaemia (Hb<110.0 g/L), weight-for-height, weight-for-age z-score (WAZ), underweight (WAZ<-2) and child development measured by the Global Scales of Early Development (GSED). Outcomes were analysed intention to treat using adjusted linear and logistic regression models and compared each of the three interventions to the control group. Assessors and analysts were blinded to the treatment-blinding of participating families was not possible.

Results: A total of 2291 caregiver-child dyads across the 282 study clusters were included in the study. 70 clusters (557 dyads) were assigned to the control group, 70 clusters (643 dyads) to growth charts only, 71 clusters (525 dyads) to SQ-LNS and 71 clusters (566 dyads) to SQ-LNS and growth charts. SQ-LNS improved HAZ by 0.21 SD (95% CI 0.06 to 0.36) and reduced the odds of stunting by 37% (adjusted OR, aOR 0.63, 95% CI (0.46 to 0.87)). No HAZ or stunting impacts were found in the growth charts only or growth charts+SQ LNS arms. SQ-LNS only improved WAZ (mean difference, MD 0.17, 95% CI (0.05 to 0.28). No impacts on WAZ were seen for growth charts and the combined intervention. Child development was higher in the growth charts only (MD 0.18, 95% CI (0.01 to 0.35)) and SQ-LNS only arms (MD 0.28, 95% CI (0.09 to 0.46). SQ-LNS improved average haemoglobin levels (MD 2.9 g/L (0.2, 5.5). The combined intervention did not have an impact on WAZ, Hb or GSED but reduced the odds of anaemia (aOR 0.72, 95% CI (0.53 to 0.97)). No adverse events were reported.

Interpretation: SQ-LNS appears to be effective in reducing growth faltering as well as improving anaemia and child development. Growth charts also show the potential to reduce anaemia and improve child development but do not seem as effective in addressing growth faltering. Further research is needed to better understand reduced effectiveness when both interventions are combined.

Trial registration number: NCT051204272.