Longitudinal structural equation modeling (LSEM) is used to answer lifespan relevant questions such as (a) what is the effect of one variable on change in and other, (b) what is the average trajectory or growth rate of some psychological variable, and (c) what variability is there in average trajectories and what predicts this variability. The first of these questions is often answered by a LSEM called an autoregressive cross-lagged (ACL) model. The other two questions are most typically answered by an LSEM called a latent growth curve (LGC). These models can be applied to a few time waves (measured over several years) or to many time waves (such as present in diary studies) and can be altered, expanded, or even integrated. However, decisions on what model to use must be driven by the research question. The right tool for the job is not always the most complex. And, more importantly, the right tool must be matched to the best possible research design. Sometimes in lifespan research the right tool is LSEM. However, researchers should prioritize research design as well as careful specification of the processes and mechanisms they are interested in rather than simply choosing the most complicated LSEM they can find.
Philip Parker and Robert Brockman
Kathleen Someah, Christopher Edwards, and Larry E. Beutler
There are many approaches to psychotherapy, commonly called “schools” or “theories.” These schools range from psychoanalytic, to variations of insight- and conflict-based approaches, through behavioral and cognitive behavioral approaches, to humanistic/existential approaches, and finally to integrative and eclectic approaches. Different and seemingly new approaches typically have been informed by older and more established ones. For instance, cognitive behavioral therapy (CBT), one of the more widely used approaches, evolved from traditional behavior therapy but has become sufficiently distinct by adding its own complex variations so as functionally to represent an approach of its own. New approaches abound both in number and in complexity. Modern clinicians have had to become increasingly widely read and creative in trying to understand the ways in which patients may be helped. The sheer number of approaches, which has climbed into the hundreds, has challenged the field to find ways of ensuring that the treatments presented are effective. The advent of Evidence Based Practices (EBP) throughout the healthcare fields has placed the responsibility on those who advocate for particular types of treatment scientifically to demonstrate their efficacy and effectiveness. While this movement has brought standards to the field and has offered some assurance that psychotherapy is usually helpful, there remains much debate about whether the many different schools produce different results from one another. The debate about how best to optimize positive effects of psychotherapy continues, and there remain many questions to be asked of psychotherapy theories and of research on these approaches.