Studi ini bertujuan untuk menguji reliabilitas dan validitas dari sebuah alat ukur mengenai perilaku ketegasan dalam keluarga dan pasangan. Survey diberikan kepada 141 mahasiswa/i University of Queensland yang terdaftar di kelas alat ukur Psikologi. Setelah semua data diperoleh, skala pengembangan alat ukur perilaku ketegasan (ICYRAS) diuji dalam segi reliabilitas, Items Diskriminasi Indeks dan validitas dalam kaitannya terhadap RAS dan alat ukur harga diri (RSES). Hasil mendukung dua hipotesis yang menunjukan bahwa alat ukur ICYRAS berhasil memiliki reliabilitas yang baik antar items. Setidaknya hanya satu item yang perlu untuk direvisi. Alat ukur ini dapat diaplikasikan diluar pendekatan klinis dan butuh penelitian lebih lanjut untuk memvalidasi penggunaannya dengan variabel lainnya.

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The present study aims to test the reliability and validity of a new developed measure of assertiveness in relationship with family and significant other. Surveys were administered toward 141 university students of The University of Queensland who enrolled in Measurement in Psychology class. After all the data were obtained, the developed scale of assertiveness (ICYRAS) was tested on its reliability, Item Discrimination Indices, and validity in conjunction with RAS, and self-esteem (RSES). Results have supported the two hypotheses that indicate the developed ICYRAS shown to have good reliability among its items and good discriminating indices with at least one item that needs rewording. This developed scale is applicable to non-clinical settings and need further research to validate its use with other variables.