Problem
Given that most quantitative research explores the relationships between variables, please assess the limitations of and/or strengths of the study design with a specific focus on the drawing of causal conclusions. If the study is an experiment, discuss the threats to internal validity that are most relevant. For instance, which key threats cause problems? Which do not? What aspects of research design (i.e., random assignment to groups) prevent and/or facilitate the drawing of causal conclusions? If the study is not an experiment then, rather than discussing the threats to internal validity, use more general language, that is, speak in terms of possible confounding variables and related issues that may affect the drawing of causal conclusions.
Article: "Development of a protective mental work demands questionnaire" by Felix S. Hussenoeder , Ines Conrad , Steffi G. Riedel-Heller and Francisca S. Rodriguez.