<qa>  How many pre-diabetic subjects will take part in the study?This study evaluates the performance and safety of the fluorescence based fibre optic glucose sensor for home usage.24 subjects will take part in the study, including 4 pre-diabetic subjects, 8 Type I diabetic patients, 8 Type II diabetic patients and 4 diabetic patients who require continuous ambulatory peritoneal dialysis CAPD. Type 1, Type 2 and prediabetic subjects will wear one FiberSense sensor, randomly allocated to either the upper arm 50 or abdomen 50 for 28 days. In addition, these subjects will wear a Dexcom sensor on the other side of the abdomen for 7 days in one of the four study weeks. In all 4 CAPD subjects, one FiberSense sensor will be placed in the upper arm for 28 days. No additional comparator sensor will be placed in CAPD subjects. 