The Usability of a Hybrid Closed-Loop Insulin Delivery System: Simulated Use Studies of the t:slim X2 Pump With Control-IQ Technology

Preston Sobel, Nancy Terjung, Betsy Dokken, Ian Cadieux, Garrett Marin, Jason Farnan

Objective

To assess the usability and safety of a touchscreen, wearable insulin pump with an operating system that automatically adjusts insulin delivery based on a) predicted continuous glucose monitoring (CGM) readings and b) user input that informs the insulin pump of food intake and activity levels.

Method

70 participants, composed of insulin pump users and multiple daily injection (MDI) users, completed the usability studies. The participants were given real-life scenarios as context for simulated use tasks and knowledge tests.

Results

The average SUS scores for the formative and summative tests were identical at 84, indicating a high user satisfaction (typical scores 65-75). Task completion rates of 93% and 96% were observed, respectively.

Conclusion

The findings indicate that the t:slim X2 insulin pump with an advanced hybrid closed-loop insulin delivery system from Tandem Diabetes Care, in simulated use, was both intuitive and safe to use.

View Abstract

Responsible Use of Control‑IQ Technology

Even with advanced systems such as Control-IQ technology, users are still responsible for actively managing their diabetes. Control-IQ technology does not prevent all high and low blood glucose events. The system is designed to help reduce glucose variability, but it requires that users accurately input information, such as meals and periods of sleep or exercise. Control-IQ technology will not function as intended unless all system components, including CGM, infusion sets and pump cartridges, are used as instructed. Importantly, the system cannot adjust insulin dosing if the pump is not receiving CGM readings. Because there are situations and emergencies that the system may not be capable of identifying or addressing, users should always pay attention to their symptoms and treat accordingly.

Important Safety Information

RX ONLY. The t:slim X2 pump and Control-IQ technology are intended for single patient use. The t:slim X2 pump and Control-IQ technology are indicated for use with U-100 insulin only.

t:slim X2 insulin pump : The t:slim X2 insulin pump with interoperable technology is an alternate controller enabled (ACE) pump that is intended for the subcutaneous delivery of insulin, at set and variable rates, for the management of diabetes mellitus in people requiring insulin. The pump is able to reliably and securely communicate with compatible, digitally connected devices, including automated insulin dosing software, to receive, execute, and confirm commands from these devices. The t:slim X2 pump is indicated for use in individuals six years of age and greater. Control-IQ technology: Control-IQ technology is intended for use with a compatible integrated continuous glucose monitor (iCGM, sold separately) and ACE pump to automatically increase, decrease, and suspend delivery of basal insulin based on iCGM readings and predicted glucose values. It can also deliver correction boluses when the glucose value is predicted to exceed a predefined threshold. Control-IQ technology is intended for the management of Type 1 diabetes mellitus in persons six years of age and greater.

Warning: Control-IQ technology should not be used by anyone under the age of six years old. It should also not be used in patients who require less than 10 units of insulin per day or who weigh less than 55 pounds.

Control-IQ technology is not indicated for use in pregnant women, people on dialysis, or critically ill patients. Do not use Control-IQ technology if using hydroxyurea. Users of the t:slim X2 pump and Control-IQ technology must: use the insulin pump, CGM, and all other system components in accordance with their respective instructions for use; test blood glucose levels as recommended by their healthcare provider; demonstrate adequate carb-counting skills; maintain sufficient diabetes self-care skills; see healthcare provider(s) regularly; and have adequate vision and/or hearing to recognize all functions of the pump, including alerts, alarms, and reminders. The t:slim X2 pump, transmitter, and sensor must be removed before MRI, CT, or diathermy treatment. Visit www.tandemdiabetes.com/safetyinfo for additional important safety information.

The Usability of a Hybrid Closed-Loop Insulin Delivery System: Simulated Use Studies of the t:slim X2 Pump With Control-IQ Technology

Objective

Method

Results

Conclusion

Software

Information

Disclosures