Conceptualizing,Capturing, and Modeling Change: Challenges for Psychology

A primary goal of scientists, be they psychologists or physicists, is the detection of cause‐and‐effect relationships. In whatever field of study, the impact of the independent variable upon the dependent variable is assessed either indirectly through presumed change (comparing groups cross‐sectionally) or directly through observed change (comparing a single entity or groups of entities longitudinally). Researchers' conceptualization of change varies quite dramatically, even within the field of psychology, with attendant variation in research designs and statistics commonly employed. We discuss the array of options available to conceptualize, capture, and model change, including their strengths and weaknesses, using examples from our own research in personality lifespan development, along with others' related research.