June 2020

Objective: To investigate the method, learning and challenges of using an enhanced sample to provide small area data for the dental survey of five-year-old children in England.   Design: Pilot in six London local authorities, of increased sample size during a national survey to enable a more precise sample size calculation to deliver information accurate at electoral ward level. Challenges were explored through interviews with the teams who either planned or conducted the survey. Main outcome measures: A revised sample size recommendation for the national guidance on carrying out dental surveys of five-year-old children in England, where caries levels are similar to those seen in the pilot areas; the challenges identified were gaining access to schools and consent from parents, making the calculation for the additional sample and securing sufficient workforce. Conclusion: This paper has described a method for delivering small area caries data by increasing the size of the sample. Learning, and understanding the outcomes and challenges from this work can inform planning and delivery of future surveys using an enhanced sample at ward level. Public health competencies being illustrated Dental public health intelligence Drawing valid inferences from qualitative and quantitative analysis