*4.4. Recommendations for Future Research*

Additional research evaluating regionally-validated tools, conducted in large and diverse study populations with adequate follow-up, including low-and middle-income countries, are needed to understand whether these tools can be used to predict long term outcomes and assess the impact of interventions. Existing data from large cohort studies in these low-and middle-income countries, either ongoing or already completed, could also be leveraged to contribute to this field of work. Many of the tools evaluated in our review were proprietary, and there is growing interest in developing tools that are valid across multiple populations and that can be administered by medical staff or community health workers [33]. Additionally, to address the limitation of the inability to capture all potentially relevant development tools of interest, researchers conducting future research on this topic could consider not restricting their search to specific tools, but instead develop a detailed search string on keywords related developmental domains.
