Loseke, D. (2017). 5 measurement. In Methodological thinking: Basic principles of social research design (pp. 71-86). SAGE Publications. Read Chapter 5: “Measurement”
Barton, B., & Peat, J. (2014). Medical statistics: A guide to spss, data analysis and critical appraisal. ProQuest Ebook Central Read Chapter 1: “Creating an SPSS Data File and Preparing to Analyse the Data”