Evidence and context
A funding period defines when particular activities and obligations are supported. The question of what those activities changed may require a different observation period.
Hamory and colleagues studied economic outcomes up to twenty years after a randomized school deworming intervention in Kenya. Their findings illustrate the value of sustained follow-up in that setting. They should not be treated as a prediction for every health intervention or a reason to delay all evaluation until decades have passed. Proceedings of the National Academy of Sciences, 2021
For program design, the practical issue is which questions can reasonably be answered by the planned closing date. A team may be able to report delivery and early uptake, while durability or longer-term effects remain open.
An illustrative scenario is a program supporting a new service model. At close, the team can document implementation and early use. Whether the service remains available after external support ends may need a later check. The first report can be complete about the period it covers without pretending to settle the second question.
A responsible account of program outcomes should make the time horizon visible. It should explain both what the evidence can establish today and what remains worth learning later.
Implications for research and practice
Funding duration and outcome timing can differ. Follow-up design should match the expected trajectory of change, with resources and responsibilities identified.
Scope and limitations
This is a selective narrative brief based on the linked publications, not a systematic review or a new empirical study. Illustrative scenarios and practice implications are editorial analysis. Findings should be interpreted within the settings, methods and observation periods of their original sources.