Final answer:
The statistical technique where researchers group items on a questionnaire is called Factor Analysis, which is used to identify underlying relationships between questions, unlike Regression Analysis which examines relationships between a dependent variable and independent variables.
Step-by-step explanation:
When researchers group items on a questionnaire using a statistical technique, that method is called Factor Analysis. Factor analysis is a complex statistical method used to describe variability among observed, correlated variables in terms of a potentially lower number of unobserved variables called factors. It is often used in questionnaire design to identify underlying relationships between individual questions.
The Regression Analysis is used for determining the strength and direction of the relationship between a dependent variable and one or more independent variables. Pretest Analysis and Effect Size Analysis are different concepts: pretests are conducted to refine procedures or instruments, and effect size analysis refers to the quantification of the difference between two groups.