Factory calibration describes how a system establishes its sensor-to-glucose relationship without routine calibration by the user. It does not establish perfect accuracy or remove every situation in which a separate blood glucose check may be needed.
Three terms to keep distinct
| Term | What it means | What to verify |
|---|---|---|
| Calibration | Establishing or updating the relationship used to convert a sensor signal to glucose | Whether the exact system requires, permits or does not use user calibration. |
| Confirmation | A separate meter check used in a situation defined by the instructions or care plan | When the device instructions require a check and what to do with the result. |
| Warm-up | The startup interval before the system makes readings available | The labeled duration and what the supplied system displays during startup. |
Factory calibrated does not mean “never check”
The ADA 2026 guidance notes that few current real-time systems require user calibration, while access to a blood glucose meter remains necessary for questionable readings and interruptions. Optional or required calibration procedures are model-specific; do not enter values using a method borrowed from another brand.
Warm-up is also device-specific. Do not use a regional product description as a universal interval for every CGM. A startup period reflects the system’s defined workflow; its duration alone is not an accuracy ranking.
For the VivaChek regional GS1 reference
The cited regional GS1 page describes a 60-minute pairing warm-up. Keep that number attached to that source and compare the instructions supplied with the exact device. Our GS1 product guide records the context and other published specifications.
Should I calibrate whenever the sensor and meter differ?
Use your own system’s instructions and professional guidance. Calibration and confirmation are different actions; not every system accepts user calibration, and a difference does not justify inventing a calibration procedure.
This is general educational information. Use the instructions for the exact device and discuss personal glucose results or treatment questions with your healthcare professional.
Original sources
- American Diabetes Association · Diabetes Technology, Standards of Care 2026
- MARD methodological review
- Regional GS1 description
Sources reviewed 18 October 2026. Model features and local access should be checked against the current instructions and market record.