Averting the Next Credibility Crisis in Psychological Science: Within-Person Methods for Personalized Diagnostics and Intervention

Causal inference on human behaviour

Making causal inferences regarding human behaviour is difficult given the complex interplay between countless contributors to behaviour, including factors in the external world and our internal states. We provide a non-technical conceptual overview of challenges and opportunities for causal inference on human behaviour. The challenges include our ambiguous causal language and thinking, statistical under- or over-control, effect heterogeneity, interference, timescales of effects and complex treatments. We explain how methods optimized for addressing one of these challenges frequently exacerbate other problems. We thus argue that clearly specified research questions are key to improving causal inference from data. We suggest a triangulation approach that compares causal estimates from (quasi-)experimental research with causal estimates generated from observational data and theoretical assumptions. This approach allows a systematic investigation of theoretical and methodological factors that might lead estimates to converge or diverge across studies.

Person, Population, Mechanism. Three Main Branches of Psychological Science

There are different ways of dividing psychology into subdisciplines. The purpose of the present paper is to explore one specific meta-perspective on psychological science, seen as having three main branches: person psychology, population psychology, and mechanism psychology, linked to three different levels of research. Person-level research focuses on psychological phenomena as experienced and enacted by individual persons in their interaction with other persons and other parts of the environment, and in their development over time. Population-level research focuses on populations of individuals, frequencies of various psychological phenomena in a population, risk factors, and population-level effects of various psychological interventions. Mechanism-level research focuses on psychological functioning as explained in terms of neurophysiological mechanisms and information processes at a sub-personal level. It is argued that the failure to differentiate clearly between research questions at these three levels lead to questionable research practices. Most notably, a failure to differentiate clearly between the population level and the person level leads to problem-method mismatches in the form of researchers trying to answer questions about persons by research on populations. Also, because of a failure to differentiate between the person level and the mechanism level, explanations in terms of sub-personal mechanisms are too often seen as providing answers about what occurs at the person level, thereby failing to study persons as intentional agents in interaction with other persons and other parts of the environment. It is argued that a clear differentiation between three levels of psychological science - population, person, and mechanism - may contribute to an increased clarity in these matters and may thereby contribute to the development and maturation of psychological science.

The direction of effects between parenting and adolescent affective well-being in everyday life is family specific

Numerous theories and empirical studies have suggested that parents and their adolescent children reciprocally influence each other. As most studies have focused on group-level patterns, however, it remained unclear whether this was true for every family. To investigate potential heterogeneity in directionality, we applied a novel idiographic approach to examine the effects between parenting and adolescent well-being in each family separately. For 100 days, 159 Dutch adolescents (Mage = 13.31, 62% female) reported on affective well-being and four parenting dimensions. The family-specific effects of pre-registered ( https://osf.io/7n2jx/ ) dynamic structural equation models indeed revealed that a reciprocal day-to-day association between parenting and adolescent affective well-being was present only in some families, with the proportion of families displaying a reciprocal association varying across the four parenting dimensions (11-55%). In other families, either parenting predicted the adolescent's affective well-being (8-43%) or vice versa (10-27%), or no day-to-day associations were found (16-60%). Adolescents with higher trait levels of environmental sensitivity and neuroticism were more strongly affected by parenting. Thus, findings suggest that the ways in which parents and adolescents influence each other in everyday life are unique, stressing the need to move towards an idiographic parenting science.

Temporal associations between depressive symptoms, self-esteem, and satisfaction with family life: A 15-year study

Introduction

In South Korea, depression has significant economic and social impacts, including increased healthcare costs and a relatively high suicide rate. Reducing the prevalence of depressive symptoms in the general population is therefore an important public health goal in this country. To achieve this goal, it is essential to identify the factors that may increase or decrease the risk of depression. This study examined the association between depressive symptoms and two indicators of wellbeing: self-esteem and satisfaction with family life. A primary objective was to examine whether higher self-esteem and satisfaction with family life could predict a decrease in depressive symptoms in the future.

Methods

A large representative sample was used, collected over a 15-year period with annual lags. The random intercept cross-lagged panel model was used to examine reciprocal associations between the 3 variables at the within-person level.

Results

All within-person effects were found to be reciprocal, significant, and in the expected direction. Thus, within-person deviations in any of the variables are associated with future within-person deviations in the other variables.

Discussion

These results suggest that indicators of positive mental health (self-esteem and satisfaction with family life) are protective factors against future depressive symptoms. In addition, depressive symptoms are risk factors for lower self-esteem and lower satisfaction with family life.

The Central Role of the Concept of Person in Psychological Science

The first article in the present issue of JPOR is written by two pioneers in person-oriented research, John Nesselroade and Peter Molenaar. Among other things they argue that the individual is the primary unit of analysis for studying behaviour, and that this is in line with a growing emphasis on personalized diagnoses and treatment regimens in medicine, which reflects a renewed emphasis on focusing on the individual person. As was argued by Julia Moeller in a previous article in JPOR, however, psychological science seems to “lag behind” in this respect, with a concomitant risk of a credibility loss. One problem is that psychology still lack a coherent theoretical paradigm that places the person at the center of the stage. Some promising theoretical work on the concept of person has been carried out by researchers such as Mark Bickhard and Peter Ossorio, and it is possible that the future will see an increased cross-fertilization between (1) the theoretical development of a comprehensive model of the person and (2) methodological developments that facilitate the study of developmental processes at the level of the individual person.

[Growth trajectories of intrinsic value beliefs in mathematics and French: Relations with career orientations]

This longitudinal study investigated different trajectories in the development of intrinsic value beliefs in the subjects Mathematics and French in Grades 9 to 11 and their correlations with career aspirations. Using data from 850 students from German-Swiss high schools (54% female, age T1: 15.6 years), five distinct growth classes were identified in a bivariate growth model. Two of these classes showed clear differentiation between intrinsic value beliefs regarding the two subjects and stable growth in the preferred subject. The other three classes were characterized by mean differences (high, medium, low intrinsic value beliefs) and moderate decline in both subjects. The five growth classes were associated with different career orientations at the end of the 11th grade, with students exhibiting particularly high career orientations in one subject when intrinsic value regarding the other subject was low. Gender differences in career orientations could be fully explained by gender membership in the five growth classes.