How does the Quick value differ from the INR value?

The INR value (International Normalized Ratio) represents a standardized variant of the quick value, which provides better comparability of the values across laboratories and thus, depending on the laboratory, is subject to fewer fluctuations. For this reason, the INR value is increasingly replacing the quick value in everyday clinical practice. In comparison, an increased INR value indicates an extended clotting time.

With the Quick value, the percentage decreases with longer coagulation time. This can initially lead to confusion for the layperson. In general, the INR value detects the same characteristics of the blood coagulation system as the Quick value, but it is simply more comparable through standardization.

In different test procedures, the Quick value simply showed different results that are difficult to compare with each other. The standard value of the INR is 1.0. If a prolonged coagulation time occurs, e.g. in anticoagulant therapy to prevent thrombosis, the value is between 2.0 and 3.5.

What happens if the Quick is too high?

The quick-value represents the duration of the clotting time of a standard value of the normal population and is calculated as a percentage. For a well functioning coagulation it should be greater than 70%. Unusually for percentages, the Quick may also exceed 100%, which is why the standard value is given in the literature as 70-130%.

Basically, a too high Quick value, i.e. a fast clotting time, has no disease value. The Quick detects the extrinsic side of the coagulation chain reaction, which can be triggered by vascular injury. Reliable, fast clotting is a good prerequisite for preventing bleeding.Dangers are more likely to arise if the Quick value is too low. This is less than 70% for the desired therapeutic effect, or even lower depending on the desired target value. If the Quick value is far below the target value, this means a much longer coagulation time, which can lead to complications such as bleeding.