Worksheets on Edexcel GCSE Psychology 11.1 Designing psychological research, covering 11.1.1 Identify variables, 11.1.2 Controlling extraneous variables, 11.1.3 Write a null hypothesis, 11.1.4 Write an alternative hypothesis, 11.1.5 Methods of sampling, 11.1.6 Experimental and research designs, 11.1.7 Reliability and validity, 11.1.8 Ethical issues in research, 11.1.9 Laboratory experiment, 11.1.10 Field experiment, 11.1.11 Natural experiment, 11.1.12 Interview, 11.1.13 Questionnaire, 11.1.14 Correlation, 11.1.15 Case study, and 11.1.16 Observation, with answers. Print them, or work through one on screen. Write your working straight onto the paper and Genie marks it question by question against the mark scheme.