Trimmed Spearman-Karber method.

The MATLAB function in TSK.m analyzes a dose-response curve and calculates the median dose (for instance, the lethal dose for 50% of the population (LD50)) using the Trimmed Spearman-Karber method. This is an alternative to dose-response analysis methods such as probit and logit methods. It does not require glmfit or the stats toolbox.

All calculations in this code are based on the method from Hamilton, M.A.; Russo, R.C.; Thurston, R.V. Trimmed Spearman-Karber Method for Estimating Median Lethal Concentrations in Toxicity Bioassays. Enviro. Sci. Tech. 1977, 11 (7), 714-719: http://dx.doi.org/10.1021/es60130a004. See also ibid, 1978, 12 (4), 417: http://dx.doi.org/10.1021/es60140a017.

This code was validated using the data given in Hamilton et al. (1977) and the example given in the documentation for the EPA's DOS program to perform the Spearman-Karber method. (Note that the confidence intervals given in Hamilton et al. (1977) are incorrect, as per Hamilton et al. (1978).) This code replicates the EPA program's results. Hamilton's test cases are provided in TSKTest.m.