Comparison of several coproparasitological techniques for diagnosis of soil-transmitted helminthiasisFive hundred and eleven samples of feces were examined by several coproparasilological techniques: Kalo-Katz, Willis, Ritchie and direct wet mount. It was found that Kato-Katz was the most reliable technique for the diagnosis of Trichuris trichiura, Necator americanus, and Ascaris lumbricoides, demonstrating the largest number of cases. Willis, Ritchie and direct wet mount were effective in that order. Taking into account that Kato-Katz is a quantitative method, it should be recommended in the diagnosis of soil-transmitted helminthiasis.