Abstract. Soil-transmitted helminths (STH) infections or a group of parasitic nematode worms causing human infection through contact with moist soil may contribute to anemia, nutritional  disorders, physical and intellectual growth retardation. School age children are at high risk of STH infection due to frequent contact with soil. Reliable, sensitive, and practical diagnostic tests are an essential tool for detection STH infections. This study aimed to assess the sensitivity and specificity of the formol ether concentration (FEC) in the diagnosis of STH infection when compared to the Kato-Katz technique. The study was design at state elementary school 27 Peusangan, Bireuen. A total of 80 (100%) elementary students were studied of FEC technique showed that 12 (15%) sample had STH infection and Kato-Katz technique (Gold standard) showed that 31 (38,75%) sample had STH infection. The FEC technique to have sensitivity of (38.71%), specificity of (100%) and accuracy of (76.25%).

The Kato-Katz technique is better than the FEC technique for assessing STH infections in Bireuen due to mild infection.

Keywords: FEC, Kato-Katz, soil transmitted helminths