INS and Hypoglycemia: Compared with the control period, day-and-night closed-loop insulin delivery reduced the proportion of time with glucose concentration below 3·9 mmol/L by 50% (37–59, p<0·0001), below 3·5 mmol/L by 65% (53–74, p<0·0001), below 3·3 mmol/L by 70% (57–78, p<0·0001), and below 2·8 mmol/L by 76% (59–86, p<0·0001), as well as the burden of hypoglycaemia (ie, area under the curve when sensor glucose concentration was less than 3·5 mmol/L) by 73% (59–82, p<0·0001).