This text is a vital resource for those with little or no prior knowledge of computing or statistics to aid in the development of reliable and valid tests and scales for assessment or research purposes. It serves as a clear, concise and jargon-free primer for all those embarking in fieldwork or research analysis. The book contains detailed guidelines for locating and constructing psychological measures, including descriptions of popular psychological measures and step-by-step instructions for composing a measure, entering data, and computing reliability and validity of test results. Advanced techniques such as factor analysis, analysis of covariance, and multiple regression analysis are presented for the beginner. This new edition has been revised throughout and includes updated statistical test procedures in line with the new version of SPSS and the inclusion of current academic articles. It serves as an invaluable resource for undergraduates and postgraduates across the behavioral and social sciences, as well as professionals in related disciplines, including those working in management and medical sciences.