ABSTRACT
Combining classical pharmacokinetic principles with statistical models, population pharmacokinetics (popPK) can effectively utilize sparse data for pharmacokinetic analysis. An optimally designed population pharmacokinetic study will balance the efficiency of a popPK study and the precision with which the parameters are estimated to ensure the unbiased estimation of pharmacokinetic parameters and facilitate the development of clinical and non-clinical trials. Sparse sampling methods have been developed for designing population pharmacokinetic experiments including random sampling method, limited sampling strategy, maximum a posteriori Bayesian method, Fisher information matrix method, and informative block randomized design, which have been widely applied in the uni-response and multi-response popPK sampling optimization. In recent years, population pharmacokinetics has been developed rapidly in Chinese materia medica (CMM), but few studies have been conducted to optimize sampling. By comparing the advantages and disadvantages of each sparse point sampling optimization method and the applicable conditions, this work provides a comparative review of optimal design methodologies and gives its application examples, which provides a reference for pharmacokinetic sampling optimization of CMM.
ABSTRACT
Objective To optimize and simplify the survey method of Oncomelania hupensis snails in marshland endemic re-gions of schistosomiasis,so as to improve the precision,efficiency and economy of the snail survey. Methods A snail sam-pling strategy(Spatial Sampling Scenario of Oncomelania based on Plant Abundance,SOPA)which took the plant abundance as auxiliary variable was explored and an experimental study in a 50 m×50 m plot in a marshland in the Poyang Lake region was performed. Firstly,the push broom surveyed data was stratified into 5 layers by the plant abundance data;then,the required numbers of optimal sampling points of each layer through Hammond McCullagh equation were calculated;thirdly,every sample point in the line with the Multiple Directional Interpolation(MDI)placement scheme was pinpointed;and finally,the compari-son study among the outcomes of the spatial random sampling strategy,the traditional systematic sampling method,the spatial stratified sampling method,Sandwich spatial sampling and inference and SOPA was performed. Results The method(SOPA) proposed in this study had the minimal absolute error of 0.2138;and the traditional systematic sampling method had the largest estimate,and the absolute error was 0.9244. Conclusion The snail sampling strategy(SOPA)proposed in this study obtains the higher estimation accuracy than the other four methods.