Enter transfer study data
Use raw paired results for deeper comparison, or enter summary statistics directly.
Example data table
This paired study example can be entered directly into the raw result fields.
| Replicate | Sending lab result | Receiving lab result | Pair difference |
|---|---|---|---|
| 1 | 99.8 | 100.4 | 0.6 |
| 2 | 100.3 | 100.9 | 0.6 |
| 3 | 100.1 | 100.5 | 0.4 |
| 4 | 99.9 | 100.2 | 0.3 |
| 5 | 100.5 | 100.8 | 0.3 |
| 6 | 100.0 | 100.4 | 0.4 |
Formula used
Bias: Bias = Receiving Mean − Sending Mean
Bias percentage: Bias % = (Bias ÷ Sending Mean) × 100
Coefficient of variation: CV % = (SD ÷ Mean) × 100
Pooled standard deviation: sp = √[((n1−1)s1² + (n2−1)s2²) ÷ (n1+n2−2)]
Standard error of difference: SE = sp × √(1/n1 + 1/n2)
Difference statistic: |Bias| ÷ SE
Confidence interval: Bias ± z × SE
Bias acceptance window: Target × Maximum Acceptable Bias %
Readiness score: ratio of passed acceptance checks, shown as a percentage.
The confidence interval uses common z-values for the selected confidence level. This keeps the tool quick for method transfer screening and report preparation.
How to use this calculator
- Enter paired raw results from both laboratories for the richest analysis.
- Use manual means, standard deviations, and replicate counts when only summaries are available.
- Provide the target value and optional specification limits for acceptance screening.
- Set acceptable bias and precision limits according to your transfer protocol.
- Choose the desired confidence level, then calculate the transfer result.
- Review the readiness score, acceptance checks, and bias interval before making decisions.
- Download the result table as CSV or save the page as a PDF report.
Frequently asked questions
1. What does this calculator measure?
It compares sending and receiving laboratory performance using bias, precision, pooled variability, confidence limits, and pass indicators. The goal is to estimate whether a transferred analytical method performs consistently enough for routine use.
2. Can I use raw results instead of summary values?
Yes. When you enter paired raw results, the calculator derives mean, standard deviation, replicate count, pairwise error, RMSE, and correlation automatically. That gives a deeper view of transfer agreement.
3. Why are both bias and CV checked?
Bias measures systematic shift between laboratories, while CV measures repeatability relative to the mean. A method can show low bias but still fail precision expectations, so both criteria matter.
4. What is the readiness score?
The readiness score is the percentage of enabled acceptance checks that pass. It is a practical screening indicator, not a regulatory standard by itself, so pair it with your approved protocol.
5. Should specification limits always be entered?
Not always. They are helpful when transfer acceptance depends on means remaining inside product or method limits. If you leave them blank, the tool focuses on bias, precision, and interval checks.
6. What does the confidence interval show?
It estimates the likely range of mean bias between laboratories. If the entire interval stays inside your allowed bias window, the transfer shows stronger statistical support for equivalence.
7. Can this replace a full transfer protocol?
No. It supports planning, screening, and documentation, but official transfer decisions should still follow your approved protocol, method validation rules, equipment qualification status, and quality requirements.
8. When is RMSE useful here?
RMSE is useful when paired raw results are available. It summarizes typical pairwise error magnitude in the original unit, making it easier to compare transfer quality across studies.