Intermediate Precision Calculator
Compare two sets of results from different analysts, days, instruments or laboratories, with each set’s %RSD, the combined %RSD and the difference of means.
- ICH Q2(R2)
- Combined %RSD
- Difference of means
- No sign-up
Four steps, or fewer
- Set the acceptance criteria from your validation protocol.
- Paste set 1 (often the repeatability results) and set 2 side by side.
- Check each %RSD, the combined %RSD and the difference between the means.
Not sure what to enter? Press Load example to see the calculator with realistic data. Your inputs are saved in this browser, so they are still there when you come back.
How intermediate precision is evaluated
Intermediate precision shows the effect of random events within one laboratory: different days, analysts or equipment. Reproducibility compares laboratories.
Difference = | mean₁ − mean₂ |
The combined %RSD is calculated from all individual results together, not by averaging the two %RSD values. Common criteria for a drug product assay are ≤ 2.0% for each set and combined, and a difference between means of ≤ 2.0%.
References
- ICH Q2(R2) Validation of analytical procedures
- USP General Chapter <1225>
These calculators are decision support for orientation and training. They are not validated GMP software, and results must be checked against your approved method, SOP and the current pharmacopoeia or guideline before use in GMP records. Your data is processed in your browser and is not sent to Molgenium.