Promoting Educational Research Through Effective Instrument Development

The paper examined various processes of instrument development and projected two models Test Development Model TDM I and TDM II for effective instrument development in educational research. Methods of establishing validity Face Content and Construct and reliability Test Re-test Split Half Cronbach Alfa and Coefficient of Concordance of research instruments were equally highlighted. Two test theories Classical Test Theory CTT and Item Response Theory IRT were identified as significant theories associated with test development. The two statistics which form the cornerstone of classical test theory item difficulty and item discrimination for establishing item facility indexes Item Analysis were also examined. Finally the processes provided by the two models for instrument development projected in this paper as well as the two test theories which provide the logic and mathematical framework that underlie standard practices in test construction and use were recommended for the development of test instrument in educational research. Also is recommended that only items found within the acceptable difficulty index and discrimination index should be retained to form final part of the developed instrument.