Ruggedness Testing Robustness

For non-compendial procedures, the performance parameters that should be determined in validation studies include specificity/selectivity, linearity, accuracy, precision (repeatability and intermediate precision), detection limit (DL), quantitation limit (QL), range, ruggedness, and robustness [6]. Other method validation information, such as the stability of analytical sample preparations, degradation/ stress studies, legible reproductions of representative instrumental output, identification and characterization of possible impurities, should be included [7], The parameters that are required to be validated depend on the type of analyses, so therefore different test methods require different validation schemes. 

Ruggedness can be determined by an interlaboratory study with a sufficient in > 8) participating laboratories following one and the same procedure as performed by different analysts, and using operational and environmental conditions that may differ but are still within the specified parameters of the assay [1, 41]. Detailed guidance for robustness and ruggedness testing is available [42, 43],... 

To our knowledge, in the first approach described, Youden and Steiner introduced the term ruggedness test for a setup in which by means of an experimental design the influences of minor but deliberate and controlled changes in the method parameters or factors are evaluated in order to detect non-robust factors, i.e., with a large influence on the response. Controlling the latter factors avoids problems in the following interlaboratory study. 

Mulholland, M. (1996). Ruggedness tests for analytical chemistry. In Robustness of Analytical Chemical Methods and Pharmaceutical Technological Products (M. W. B. Hendriks, J. H. de Boer, and A. K. Smilde, Eds), pp. 191-232, Elsevier, Amsterdam. 

Method validation Basic method validation (short-term use, fit for purpose, little robustness), data will see expert eye prior to release Extended method validation, robustness and ruggedness tests important for unsupervised operation... 

A review of ruggedness testing methods is presented in Chapter 3 and in Chapter 5 examples are given. In these chapters procedures are described that test the robustness or ruggedness of existing methods. Hence, incorporating robustness explicitly in analytical techniques (see Section 1.1) is not discussed. 

The experiments conducted to perform ruggedness tests of measurement procedures can also be viewed as experiments to investigate robust design see, for example, Wemimont [2], and Youden [3,4]. The objective of ruggedness tests is to determine a robust measurement procedure that is a procedure that will give a consistent (and correct) result under a range of measurement conditions. 

A third term in the context of precision is robustness or ruggedness. The result of a ruggedness test indicates how tightly controlled the experimental factors should be. The detection of factors that heavily influence the results of a method leads eventually to a more reproducible method. 

Ability of method to remain unaffected by small variations in method parameters (some authors make the distinction be-between the property robustness and a ruggedness test in which deliberate changes are made in a method to assess the robustness)... 

Before an optimized method can be used in routine analysis, it has to be shown that the method is capable of doing what it is claimed to method validation). Before starting with method validation often a robustness or ruggedness test is performed. In a robustness/ruggedness test (Section 6.6) one evaluates the influence of small variations in the procedure on the performance of the method. These small variations are deliberately introduced and represent variations that could occur when a method... 

Van der Hyden, Y. Nijhuis, A. Smayers-Verbeke, J. Vandeginste, B.G.M. Massart, D.L. Guidance for robust-ness/ruggedness test in method vahdation. J. Pharm. Biomed. Anal. 2001, 24, 723-753. 

Compliance with 11CFR part 35 should provide adequate proof of the ruggedness and robustness of the system software. Method developers must consider tests to evaluate algorithm stability during the development and validation processes. 

Robustness Testing. Robustness testing studies the capacity of the method to remain unaffected by small, but deliberate variation in the method parameters. By means of a limited set of experiments (often using an experimental design approach), the critical parameters that may affect the ruggedness of the method can be identified, understood, and improvements made if necessary. 

Y.V. Heyden, A. Nijhuis, J. Smeyers-Verbeke, B.G.M. Vandeginste, D.L. Massart, Guidance for robustness/ruggedness tests in method validation, J. Pharm. Biomed. Anal. 24 (2001) 723. 

A calibration procedure has to be validated with regard to general and specific requirements under which the calibration model has been developed. For this purpose, it is important to test whether the conditions represented in Fig. 6.6 are fulfilled. On the other hand, it is to assure by experimental studies that certain performance features (accuracy, precision, sensitivity, selectivity, specificity, linearity, working range, limits of detection and of quantification, robustness, and ruggedness, see Chap. 7) fulfil the expected requirements. 

In such cases it may be possible to check on robustness and ruggedness by means of statistical tests (see Sect. 4.3). All the variations to the measured signal, apart from that of the analyte, can be considered in form of error terms see Eq. (3.6) ... 

Test of ruggedness Robustness is regarded to be an mfer-laboratory property. In this case, all the terms in Eq. (7.36) are relevant and ruggedness can be tested similar to robustness in the same three ways ... 

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