Web Services - QuoData GmbH

Web services for analytical quality assurance

In General

Within various projects QuoData GmbH developed a wide range of web applications for analytical quality assurance.

These enable their users to access specific services online.

To make use of these services only an internet connection and a browser is required.

Here you can find a selection of web applications developed by QuoData GmbH.


Computation of mean and standard deviation with the robust Q/Hampel method

This web application enables users to estimate the mean and standard deviation from a data set. The statistical parameters are computed by means of the Q/Hampel method, a robust algorithm useful for data sets with outliers.


Q/Hampel method

The Q/Hampel method is a robust statistical method for the computation of mean and standard deviation. In a first step, the standard deviation is estimated by means of the Q method, which is based on the consideration of pairwise absolute differences. This standard deviation is then used for the Hampel estimation of the mean, which is based on the principle of winsorizing.


The Q/Hampel method is more robust than the algorithm A+S, and has already been adopted in the new version of ISO 13528.


It is implemented in PROLab Plus, a software package for the evaluation of interlaboratory studies.



Open application

Precision Data

Reliability of Precision Data obtained from Interlaboratory Studies

a screenshot from our web service that calculates the reliability of precision data

QuoData developed a web service calculating the minimal required number of laboratories at a desired level of certainty in sL.




Probability of Detection

Probability of detection POD is a statistical method outlined in ISO 5725

QuoData developed a new statistical method for the analysis of the probability of detection (POD) across laboratories. The calculation is derived from the principles laid down in ISO 5725.



The basis of this method is explained in Accreditation and Quality Assurance 


“Can the usual validation standard series for quantitative methods, ISO 5725, be also applied for qualitative methods?” and 


"A new profile likelihood confidence interval for the mean probability of detection in collaborative studies of binary test methods".



Web service for determination of uncertainty of results for assessment in accordnace with Federal Soil Protection and Contaminated Sites Ordinance (Bundes-Bodenschutz- und Altlastenverordnung)

The web application automatically determines whether the test result and its uncertainty is within the limit as set by the Federal Federal Soil Protection and Contaminated Sites Ordinance (BBodSchV) or whether the test result does not permit a clear evaluation. The results are provided in tabular and graphical form.


As part of its work for the German Federal Environment Agency's (FBU) Advisory Council on Soil Investigations, QuoData has developed the concept for the statistically-sound determination of the uncertainty of results on which the web application is based.


The evaluations of the web application can be used, among other things, for the preparation of expert opinions.



Congener Profile Analysis

Dioxin and Dioxin-like Compound Congener Profile Analysis Based on Statistical Inference

QuoData developed a web service for congener profile analysis of a dataset providing a statistically based sample allocation into clusters and giving the respective uncertainty ranges of the congener profile for each cluster.


The web service is free of charge in its basic version. To make use of it you require a login. Please use the link to login/inquire about a login:


Open application


appropriate publication in Journal of Chromatography A:

Are the Results of Customary Methods for Analyzing Dioxin and Dioxin-like Compound Congener Profiles Court-Proof?


Individual Evaluation of GSR PT Samples

GSR PT Sample web service for the evaluation of results from gunshot residue PTs


This web tool enables the automatic evaluation of uploaded quality control measurements of GSR PT samples from the years 2010 to 2015 and the “standard GSR sample” offered by PLANO GmbH.


Once you have imported your data a comprehensive PDF report is created as well as a dynamic chart which provides various selection criteria for a specific evaluation.