مرکز منطقه ای اطلاع رساني علوم و فناوري - DEVELOPING AND VALIDATING A TWO TIER MENDEL GENETICS DIAGNOSTIC TEST

Abstract :

The purpose of this study was to develop a reliable and valid two-tier diagnostics instrument designed to investigate college level biology students’ understandings of genetics concepts. The Concepts Diagnostic Test was developed by using procedure that had three general steps: defining the content boundaries of the test, obtaining information about student teachers’ misconceptions, and diagnostic instrument development. During this process a concept map was created and propositional statements representing the relevant genetics concepts were listed. Additionally, common Mendelian genetics misconceptions among biology students were identified. The final Genetics Concepts Diagnostic Test consisted of 12 two-tier items. The reliability coefficient (Cronbach alpha) for the whole test was 0.73. The range of values for the discrimination index was from 0.31 to 0.72 and the overall average difficulty index was 0.46. The diagnostic instrument was administered to 120 prospective biology teachers at Marmara University. Participants consisted of 87 females and 33 males. The common misconceptions on genetics were identified through analysis of the items from the instrument. Finally, the two-tier instrument is appended.