Vaccination coverage after a mass measles vaccination campaign among children aged 6 to 59 months, Kule refugee camp, Gambella, October 2023.

The original plan for this survey, as described in the protocol, was only to include children aged 6 – 59 months. However, the vaccination campaign in practice had included children from 6 months – 5 years and a decision was then taken to include this age group in the vaccination coverage survey instead of the originally planned 6 months – 59 months. However, this meant that the sample size was achieved earlier than originally planned due to the wider age group. The sample size based on the number of children was reached much earlier than expected in terms of the number of households to visit (109 households instead of the planned 291) and data collection was stopped. As a result of this earlier stopping of data collection, there was oversampling of some zones of the camp and zone B was completely left out of the sample. This undersampling of households across the zones of the camp was addressed through post stratification weighted sampling, which is why there is a weight variable in the dataset.