Sample Size The sample for the GLOVE project is 14 participants. To date, seven adults and six children from pre-school age to school age have been recruited to the project from the project's two NHS sites, Guy's and St Thomas' (GSTT) NHS Foundation Trust and Great Ormond Street Hospital (GOSH) NHS Foundation Trust respectively. All the GLOVE participants will be invited to participate in the proof of concept study, subject to meeting the inclusion criteria.