Changes in Person-reported Outcomes and Behavior Using the Accu-Chek SmartGuide CGM and Predict App

Change in overall sleep quality from baseline to follow-up, assessed using the Pittsburgh Sleep Quality Index (PSQI), a self-report questionnaire assessing sleep quality and disturbances over the previous month. Total scores range from 0 to 21, with higher scores indicating poorer sleep quality.

Change in confidence in preventing and managing hypoglycemia from baseline to follow-up, assessed using the Hypoglycemic Confidence Scale (HCS), a 9-item self-report questionnaire assessing confidence in staying safe from hypoglycemia-related problems. The mean scores range from 1 to 4, with higher scores indicating greater confidence.

Change in diabetes distress from baseline to follow-up, assessed using the 17-item Diabetes Distress Scale (DDS-17), a self-report questionnaire assessing diabetes-related emotional burden, regimen-related distress, physician-related distress, and interpersonal distress. The mean score ranges from 1 to 6, with higher scores indicating greater diabetes distress.

Change in diabetes-related empowerment from baseline to follow-up, assessed using the 8-item Diabetes Empowerment Scale-Short Form (DES-SF), a self-report questionnaire assessing psychosocial self-efficacy in diabetes self-management. Mean scores range from 1 to 5, with higher scores indicating greater diabetes-related empowerment.

Daily subjective sleep quality will be assessed using ecological momentary assessment (EMA) on a 0-3 rating scale with one prompt per day in the morning. Higher scores indicate better sleep quality. Changes in sleep quality will be analyzed at the daily level across the assessment periods.

Fear of hypoglycemia will be assessed using ecological momentary assessment (EMA) on a 0-10 rating scale with one prompt per day in the morning. Higher scores indicate reduced fear of hypoglycemia. Changes in scores will be analyzed at the daily level across the assessment periods.

Diabetes and glycemic-specific distress will be assessed using ecological momentary assessment (EMA) on a 0-10 rating scale with one prompt per day in the evening. Higher scores indicate higher distress. Changes in scores will be analyzed at the daily level across the assessment periods.

Use of and responses to CGM features will be assessed using ecological momentary assessment (EMA). Assessments will cover the use of and responses to glucose trend arrows, the use of and responses to glucose alarms, glucose alarm settings, and the use of and responses to predictive features. Changes in these behaviors will be analyzed across the assessment periods.

Changes in Glycemic outcomes across the assessment period will be assessed using continuous glucose monitoring (CGM) data and expressed as the percentage of time spent in the following glucose ranges: 70-180 mg/dL (time in range), 70-140 mg/dL, below 70 mg/dL, below 54 mg/dL, above 180 mg/dL, and above 250 mg/dL.

Changes in Glucose variability (%) across the assessment period will be assessed using continuous glucose monitoring (CGM) data and expressed as the coefficient of variation (CV), calculated as the standard deviation of glucose levels divided by the mean glucose level, multiplied by 100.

Changes in mean glucose concentration will be assessed using continuous glucose monitoring (CGM) data and reported in mg/dL.

Qualitative interviews will be conducted at the end of the study to explore participants' personal experiences, expectations, and experiences using the continuous glucose monitoring (CGM) system and its predictive features. Topics will include perceived benefits and disadvantages, experiences with handling the features, expectations, and suggestions or wishes for future improvements.