The development of ecosystem misconception diagnostic test

Misconception is a problem that is often found in learning biology concepts. Ecosystem concept is one of the biology concepts in which misconceptions are found a lot. As a learning problem, misconceptions need to be addressed as soon as possible. The purpose of this research is to produce a valid and reliable diagnostic test instrument for misconceptions in the form of a three-tier multiple choice test which is presented through Google Form platform. This development research applied the research and development method with a 4D development model. The developed diagnostic test instrument was validated by two expert validators and obtained a mean score of 3.27 (very feasible). Through the results of item validation, from 40 questions there are 30 valid items with an average correlation coefficient value of 0.67 and 10 invalid items with an average correlation coefficient value of 0.10. The diagnostic test instrument was also tested for readability to students and got an average value of 3.41 (very feasible) and was tested for readability to teachers and got an average value of 3.74 (very feasible). This shows that the developed product is very valid and reliable to be used as a diagnostic test instrument for misconceptions