Whole blood glucose- causes of false results
| Problem | Results | Recommendation |
|---|---|---|
| Sensor strips not fully inserted into meter | false low | always be sure strip is fully inserted into meter |
| Patient sample site (eg, the fingertip) is contaminated with sugar | false high | always clean test site before sampling |
| Not enough blood applied to strip | false low | repeat test with a new sample |
| Batteries low on power | error codes | change batteries and repeat sample collection |
| Test strips/Controls stored at temperature extremes | false high/low | store kit according to instructions |
| Patient is dehydrated | false high/low | do not use glucose meter. Send stat venous sample to the lab |
| Patient is in shock | false low | do not use glucose meter. Send stat venous sample to the lab |
| Squeezing fingertip too hard because the blood is not flowing | false low | repeat test with a new sample from a new puncture site |
| Sites other than fingertips | high/low | results from alternative sites may not match finger stick results |
| Test strip/'Control" solution vial is cracked or leaking | false high/low | always inspect package for cracks, leaks, etc. |
| Anaemia/decreased haematocrit | false high | send stat venous sample to the lab |
| Polycythaemia/increased haematocrit | false low | send stat venous sample to the lab |
This chart is used with kind permission from the US Food and Drug Administration Office of In Vitro Diagnostic Device Evaluation and Safety Center for Devices and Radiological Health. This web site is an excellent source of information on laboratory safety and POCT.
Additionally, on this website you will find the excellent document:
"Glucose Meter Test Results: Useful Tips to Increase Accuracy and Reduce Errors".
