Table 1

Attributes and levels for the discrete choice experiment

AttributesLevel 1Level 2Level 3Level 4
Precision compared with finger pricking‡Less accurate than finger pricking (higher or lower by 0.6 mmol/L (*10.8 mg/dL†)Less accurate than finger pricking (higher or lower by 0.3
(*5.4 mg/dL†)
Accurate as finger pricking†
Average number of finger pricks per day§4‡20
Effort to check¶High effort: you need to measure your glucose levels yourselfModerate effort: you scan a sensor to check glucose levelsLow effort: glucose levels automatically sent to you†
Probability of getting skin irritation or redness**35% chance of skin irritation or redness20% chance of skin irritation or redness5% chance of skin irritation or rednessNo chance of skin irritation or redness‡
Monthly costs††€250 (*550zl)€175 (*390zl)€100 (*220zl)€25 (*55zl)
Glucose information‡‡Current glucose level†Current Glucose level and arrowCurrent glucose level and a graphic of your level trends over the day
Alarms§§No‡Yes
  • *Unit equivalents shown for Polish survey.

  • †Reference level.

  • ‡Attribute explanation as presented to patients: Some glucose monitors are more precise than others. Finger pricking is generally regarded as the most accurate way to measure glucose levels. Measurements from devices that use sensors can be just as accurate but can also be less accurate than finger pricking, especially if your glucose levels are very high or very low. For example, if your glucose level is 6 mmol/L and you measure it with a device that is off by 0.6 mmol/L, then this device can say your glucose is anywhere from 5.4 to 6.6 mmol/L

  • §Attribute explanation as presented to patients: This is how many times you would need to do a finger-prick test each day on an average day. This number could be higher on days when you feel the need to test more often like when you’re sick, but we want you to picture an average day. Sometimes, this is your only method of measuring your glucose levels or you might need to do finger-prick tests to confirm the levels from another device.

  • ¶Attribute explanation as presented to patients: This means how much effort you need to give to check your blood glucose levels. High effort checking means you need to stop what you’re doing and concentrate on measuring your levels. You need to wash your hands, get out your device equipment, prick your finger, put blood on a strip, check the results and then clean everything up. Moderate effort checking means you need to get out a small device and use it to scan the sensor on your body to obtain your glucose levels. Low-effort checking means your glucose levels are automatically sent to a device which you can view at any time. This could be a dedicated glucose device, your phone or a smartwatch. You do not need to do anything to have your blood glucose levels sent through, just look at the device to check.

  • **Attribute explanation as presented to patients: A chance of skin irritation or redness around a sensor means a redness or itchy rash on the skin around or under the sensor. This is similar to having an itchy allergic reaction and can be rather uncomfortable or irritating. The sensor will need to be removed and replaced in a different spot. This skin irritation and redness usually last until after the sensor is replaced. Not all sensors have this side effect, so chances of getting the side effect can differ per device. If a device gives you a 15% chance, this means that 15 out of a 100 people who get this device experience skin irritation and redness, while 85 out of a 100 people do not experience this.

  • ††Attribute explanation as presented to patients: This means how much money you need to pay out-of-pocket per month in order to check your blood glucose. Please note that this is money that is not reimbursed by your insurance. This could be money needed to pay for devices, sensors, or strips used.

  • ‡‡Attribute explanation as presented to patients: This means how your glucose levels are presented to you. This information could be only your current glucose level (you only see a digital number like 8.3 mmol/L). This could be your current glucose level with an arrow showing how your blood glucose is changing as compared to your previous measurement (increasing, decreasing or stable). Or it could show your current glucose level with a graphic of your blood glucose levels over the day.

  • §§Attribute explanation as presented to patients: Your device will give you a beeping alarm (like a phone notification) any time your blood glucose levels are (getting) too high or too low.