Search

This special issue is a collection of papers inspired by Dr. Molenaar's work and innovations - a tribute to his passion for advancing science and his ability to ignite a spark of creativity and innovation in multiple generations of scientists. Following Dr. Molenaar's creative breadth, the papers address a wide variety of topics - sharing of new methodological developments, ideas, and findings in idiographic science, study of intraindividual variation, behavioral genetics, model inference/identification/selection, and more.

With the increased use of time series data in human research, ranging from ecological momentary assessments to data passively obtained, researchers can explore dynamic processes more than ever before. An important question researchers must ask themselves is, do I think all individuals have similar processes? If not, how different, and in what ways? Dr. Peter Molenaar's work set the foundation to answer these questions by providing insight into individual-level analysis for processes that are assumed to differ across individuals in at least some aspects. Currently, such assumptions do not have a clear taxonomy regarding the degree of homogeneity in the patterns of relations among variables and the corresponding parameter values. This paper provides the language with which researchers can discuss assumptions inherent in their analyses. We define strict homogeneity as the assumption that all individuals have an identical pattern of relations as well as parameter values; pattern homogeneity assumes the same pattern of relations but parameter values can differ; weak homogeneity assumes there are some (but not all) generalizable aspects of the process; and no homogeneity explicitly assumes no population-level similarities in dynamic processes across individuals. We demonstrate these assumptions with an empirical data set of daily emotions in couples.

Gender is person-specific, and it influences and is influenced by a breadth of multidimensional psychological factors, including cognition. Directionality is important for research on gender and cognition, as debate surrounds, for instance, whether masculine self-concepts precede spatial skills, or whether the reverse is true. In order to provide novel insights into the individualized nature of these relations, a person-specific network approach devised by Peter Molenaar and the first author - group iterative multiple model estimation for multiple solutions (GIMME-MS) - was applied to 75-day intensive longitudinal data on gender self-concept (i.e., femininity-masculinity, instrumentality, and expressivity) and cognition (i.e., mental rotations and verbal recall) from 103 young adults. GIMME-MS estimates individualized networks that contain same-day and next-day directed relations, prioritizing relations common across participants. It is ideal for analyzing behavioral time series with unclear directionality, as it generates multiple solutions from which an optimal one is selected. GIMME-MS revealed notable heterogeneity in the presence, direction, and nature of relations from gender self-concept to cognition (∼26% of participants) and vice versa (∼21% of participants). Findings are wholly novel in revealing the person-specific nature of gender and its cognitive dynamics, yet somehow, unsurprising given the revolutionary corpus of Peter Molenaar.

Evidence suggests that complex micro-dynamics occurring in daily life underly the development of mental distress. We aimed to (1) study the cross-lagged association between stressful events and negative affect (NA), (2) show that there is substantial between-person variability in idiographic associations and (3) show that idiographic associations are indicative of mental health. Experience sampling study assessing perceived stressfulness of events (PSE) and NA four times per day for 2 weeks in a non-clinical convenience sample (N = 70, mean age = 22.9, 61% female, 69% German). Bivariate vector autoregressive model implemented in dynamic structural equation modelling to model the associations between stressful events and NA and obtain idiographic associations. Stressfulness of events and NA were significantly reciprocally associated. Autocorrelations and cross-lagged associations from PSE to NA showed substantial variability and were significantly related with trait measures of depression, anxiety, well-being, and perceived stress. Contrary to expectations, cross-lagged associations from NA to stressfulness of events were not related to trait mental health. The approach outlined in this article is useful for studying idiographic dynamics in daily life. The findings increase our understanding of micro-dynamics underlying mental health and individual differences in these processes., (© 2024 The Author(s). Stress and Health published by John Wiley & Sons Ltd.)

Psychoneuroimmunology (PNI) is a field of research that deals with the interactions between psyche, nervous, endocrine, and immune systems. Investigating these complex PNI relationships under as ecologically valid as possible conditions ("life as it is lived") necessitates a paradigm change in research. This shift places factors such as "time" and "subjective meaning" of personal experiences at the center of the research methodology. For this purpose, the biosemiotic-systemic research design "Integrative Single-Case Study" was developed. Initial results from healthy individuals as well as patients with systemic lupus erythematosus (SLE), breast cancer, and rheumatoid arthritis (RA) support the validity of the research approach. Specifically, in connection with the occurrence of emotionally meaningful everyday incidents, we repeatedly observed stress system reactions, which were (1) delayed over several days, (2) cyclically patterned, (3) anticipatory, and (4) opposing, depending on a) whether participants experienced emotionally positive or negative everyday incidents, b) whether they were healthy or ill, and c) which stress system parameter was investigated. In this chapter, the Integrative Single-Case Study design is introduced as a holistic research option, presented in detail in its methodology, and critically discussed in terms of its limitations., (© 2025. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Idiographic measurement models such as p-technique and dynamic factor analysis (DFA) assess latent constructs at the individual level. These person-specific methods may provide more accurate models than models obtained from aggregated data when individuals are heterogeneous in their processes. Developing clustering methods for the grouping of individuals with similar measurement models would enable researchers to identify if measurement model subtypes exist across individuals as well as assess if the different models correspond to the same latent concept or not. In this paper, methods for clustering individuals based on similarity in measurement model loadings obtained from time series data are proposed. We review literature on idiographic factor modeling and measurement invariance, as well as clustering for time series analysis. Through two studies, we explore the utility and effectiveness of these measures. In Study 1 , a simulation study is conducted, demonstrating the recovery of groups generated to have differing factor loadings using the proposed clustering method. In Study 2 , an extension of Study 1 to DFA is presented with a simulation study. Overall, we found good recovery of simulated clusters and provide an example demonstrating the method with empirical data.

This study uses time-intensive, item-level assessment to examine individual depressive and co-occurring symptom dynamics. Participants experiencing moderate-severe depression (N = 31) completed ecological momentary assessment (EMA) four times per day for 20 days (total observations = 2480). We estimated idiographic networks using MDD, anxiety, and ED items. ED items were most frequently included in individual networks relative to depression and anxiety items. We built ridge and logistic regression ensembles to explore how idiographic network centrality metrics performed at predicting between-subject depression outcomes (PHQ-9 change score and clinical deterioration, respectively) at 6-months follow-up. For predicting PHQ-9 change score, R 2 ranged between 0.13 and 0.28. Models predicting clinical deterioration ranged from no better than chance to 80 % accuracy. This pilot study shows how co-occurring anxiety and ED symptoms may contribute to the maintenance of depressive symptoms. Future work should assess the predictive utility of psychological networks to develop understanding of how idiographic models may inform clinical decisions., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest regarding the publication of this article., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Challenging behaviors like aggression and self-injury are dangerous for clients and staff in residential care. These behaviors are not well understood and therefore often labeled as "complex". Yet it remains vague what this supposed complexity entails at the individual level. This case-study used a three-step mixed-methods analytical strategy, inspired by complex systems theory. First, we construed a holistic summary of relevant factors in her daily life. Second, we described her challenging behavioral trajectory by identifying stable phases. Third, instability and extraordinary events in her environment were evaluated as potential change-inducing mechanisms between different phases., Case Presentation: A woman, living at a residential facility, diagnosed with mild intellectual disability and borderline personality disorder, who shows a chronic pattern of aggressive and self-injurious incidents. She used ecological momentary assessments to self-rate challenging behaviors daily for 560 days., Conclusions: A qualitative summary of caretaker records revealed many internal and environmental factors relevant to her daily life. Her clinician narrowed these down to 11 staff hypothesized risk- and protective factors, such as reliving trauma, experiencing pain, receiving medical care or compliments. Coercive measures increased the chance of challenging behavior the day after and psychological therapy sessions decreased the chance of self-injury the day after. The majority of contemporaneous and lagged associations between these 11 factors and self-reported challenging behaviors were non-significant, indicating that challenging behaviors are not governed by mono-causal if-then relations, speaking to its complex nature. Despite this complexity there were patterns in the temporal ordering of incidents. Aggression and self-injury occurred on respectively 13% and 50% of the 560 days. On this timeline 11 distinct stable phases were identified that alternated between four unique states: high levels of aggression and self-injury, average aggression and self-injury, low aggression and self-injury, and low aggression with high self-injury. Eight out of ten transitions between phases were triggered by extraordinary events in her environment, or preceded by increased fluctuations in her self-ratings, or a combination of these two. Desirable patterns emerged more often and were less easily malleable, indicating that when she experiences bad times, keeping in mind that better times lie ahead is hopeful and realistic., (© 2024. The Author(s).)

Numerous theories suggest that parents and adolescents influence each other in diverse ways; however, whether these influences differ between subgroups or are unique to each family remains uncertain. Therefore, this study explored whether data-driven subgroups of families emerged that exhibited a similar daily interplay between parenting and adolescent affective well-being. To do so, Subgrouping Group Iterative Multiple Model Estimation (S-GIMME) was used to estimate family-specific dynamic network models, containing same- and next-day associations among five parenting practices (i.e., warmth, autonomy support, psychological control, strictness, monitoring) and adolescent positive and negative affect. These family-specific networks were estimated for 129 adolescents (M age  = 13.3, SD age  = 1.2, 64% female, 87% Dutch), who reported each day on parenting and their affect for 100 consecutive days. The findings of S-GIMME did not identify data-driven subgroups sharing similar parenting-affect associations. Instead, each family displayed a unique pattern of temporal associations between the different practices and adolescent affect. Thus, the ways in which parenting practices were related to adolescents' affect in everyday life were family specific., (© 2023. The Author(s).)

ABSTRACT Windelband ([1894]1980) advocated that two approaches are used for accumulating scientific knowledge. The first is the idiographic approach that derives knowledge from a single unit, and the second is the nomothetic approach that accumulates knowledge of a group. Given these two approaches, the former matches case studies while the latter is more appropriate with experimental group studies. Scientists have criticized both methodologies for their various limitations. Later, the single-case methodology emerged as an alternative that potentially allays these limitations. In this context, this narrative review aims to describe the historical roots of single-case experimental designs (SCEDs) that have emerged to eliminate the tension of nomothetic and idiographic approaches over time. First, the review focuses on the emergence of SCEDs. Second, the strengths and challenges of SCEDs are reviewed, including those to address the limitations of group experimental and case studies. Third, the use and analyses of SCEDs are outlined, considering their current status. Fourth, this narrative review continues to delineate the dissemination of SCEDs in the modern scientific world. As a result, SCEDs can be evaluated as a method that has the potential to overcome the issues encountered in case description and group experimental research. Thus, that helps accumulate nomothetic and idiographic knowledge in determining evidence-based practices.

Maintenance of brain structure is essential for neurocognitive health. Precision medicine has interests in understanding how maintenance of an individual person's brain, including cerebral cortical structure, interacts with lifestyle factors like physical activity. Cortical structure, including cortical thickness, has recognized relationships with physical activity, but concepts of these relationships come from group, not individual, focused findings. Whether or how group-focused concepts apply to an individual person is fundamental to precision medicine interests but remains unclear. This issue was studied in a healthy man using concurrent micro-longitudinal tracking of magnetic resonance imaging-defined cortical thickness and accelerometer-defined steps/day over six months. These data permitted detailed examination of temporal relationships between thickness maintenance and physical activity at an individual level. Regression analyses revealed graded significant and trend-level temporal interactions between preceding activity vs. subsequent thickness maintenance and between preceding thickness maintenance vs. subsequent activity. Interactions were bidirectional, delayed/prolonged over days/weeks, positive, bilateral, directionally asymmetric, and limited in strength. These novel individual-focused findings in some ways are predicted, but in other ways remain unaddressed or undetected, by group-focused work. We suggest that individual-focused concepts of temporal interactions between maintenance of cortical structure and activity can provide needed new insight for personalized tailoring of physical activity, cortical, and neurocognitive health.

Power analysis informs a priori planning of behavioral and medical research, including for randomized clinical trials that are nomothetic (i.e., studies designed to infer results to the general population based on interindividual variabilities). Far fewer investigations and resources are available for power analysis of clinical trials that follow an idiographic approach, which emphasizes intraindividual variabilities between baseline (control) phase versus one or more treatment phases. We tested the impact on statistical power to detect treatment outcomes of four idiographic trial design factors that are under researchers' control, assuming a multiple baseline design: sample size, number of observations per participant, proportion of observations in the baseline phase, and competing statistical models (i.e., hierarchical modeling versus piecewise regression). We also tested the impact of four factors that are largely outside of researchers' control: population size, proportion of intraindividual variability due to residual error, treatment effect size, and form of outcomes during the treatment phase (phase jump versus gradual change). Monte Carlo simulations using all combinations of the factors were sampled with replacement from finite populations of 200, 1750, and 3500 participants. Analyses characterized the unique relative impact of each factor individually and all two-factor combinations, holding all others constant. Each factor impacted power, with the greatest impact being from larger treatment effect sizes, followed respectively by more observations per participant, larger samples, less residual variance, and the unexpected improvement in power associated with assigning closer to 50% of observations to the baseline phase. This study's techniques and R package better enable a priori rigorous design of idiographic clinical trials for rare diseases, precision medicine, and other small-sample studies., (© 2022. The Psychonomic Society, Inc.)

Objectives: To evaluate the feasibility, usability and clinical value of daily diary assessments combined with actigraphy in older persons with cognitive impairment., Methods: For 63 days, patients ≥60 years with cognitive impairments filled out a daily diary (including standardized questionnaires and cognitive test battery), and wore an actiwatch (sleep). After the study, participants and clinicians received personal feedback about patterns and daily triggers of depressive symptoms, sleep and cognitive performance. We assessed feasibility (participation rate, compliance and subjective burden), usability (variability and floor- or ceiling effects) and clinical value for patients and their clinicians (questionnaires)., Results: Of 96 eligible patients, 13 agreed to participate (13.5%). One patient dropped out after 2 days, another after 37 days, and another did not complete the cognitive test battery. Compliance rate was high (6.7-10% missing values). Subjective burden was relatively low. Time-series data showed sufficient variability and no floor- or ceiling effects, except for one relevant ceiling effect on the One Back task. The personal feedback report was considered insightful by 4 out of 11 participants and 5 out of 7 clinicians., Conclusion: Daily assessments are suitable for a minority of cognitively impaired older persons, but is helpful to increase insight into their symptoms.

Significant heterogeneity in network structures reflecting individuals' dynamic processes can exist within subgroups of people (e.g., diagnostic category, gender). This makes it difficult to make inferences regarding these predefined subgroups. For this reason, researchers sometimes wish to identify subsets of individuals who have similarities in their dynamic processes regardless of any predefined category. This requires unsupervised classification of individuals based on similarities in their dynamic processes, or equivalently, in this case, similarities in their network structures of edges. The present paper tests a recently developed algorithm, S-GIMME, that takes into account heterogeneity across individuals with the aim of providing subgroup membership and precise information about the specific network structures that differentiate subgroups. The algorithm has previously provided robust and accurate classification when evaluated with large-scale simulation studies but has not yet been validated on empirical data. Here, we investigate S-GIMME's ability to differentiate, in a purely data-driven manner, between brain states explicitly induced through different tasks in a new fMRI dataset. The results provide new evidence that the algorithm was able to resolve, in an unsupervised data-driven manner, the differences between different active brain states in empirical fMRI data to segregate individuals and arrive at subgroup-specific network structures of edges. The ability to arrive at subgroups that correspond to empirically designed fMRI task conditions, with no biasing or priors, suggests this data-driven approach can be a powerful addition to existing methods for unsupervised classification of individuals based on their dynamic processes., (© 2023. The Author(s) under exclusive licence to The Psychometric Society.)

Research and practice in clinical neurosciences often involve cognitive assessment. However, this has traditionally used a nomothetic approach, comparing the performance of patients to normative samples. This method of defining abnormality places the average test performance of neurologically healthy individuals at its center. However, evidence suggests that neurological 'abnormalities' are very common, as is the diversity of cognitive abilities. The veneration of central tendency in cognitive assessment, i.e., equating typicality with healthy or ideal, is, I argue, misguided on neurodiversity, bio-evolutionary, and cognitive neuroscientific grounds. Furthermore, the use of average performance as an anchor point for normal performance is unreliable in practice and frequently leads to the mischaracterization of cognitive impairments. Examples are explored of how individuals who are already vulnerable for socioeconomic reasons can easily be over-pathologized. At a practical level, by valuing diversity rather than typicality, cognitive assessments can become more idiographic and focused on change at the level of the individual. The use of existing methods that approach cognitive assessment ideographically is briefly discussed, including premorbid estimation methods and informant reports. Moving the focus away from averageness to valuing diversity for both clinical cognitive assessments and inclusion of diverse groups in research is, I argue, a more just and effective way forward for clinical neurosciences.

Objective: Few studies report the psychometric properties of individualized patient-reported outcome measures (I-PROMs) combining traditional analysis and Item Response Theory (IRT)., Methods: Pre- and posttreatment PSYCHLOPS data derived from six clinical samples (n = 939) were analyzed for validity, reliability, and responsiveness; caseness cutoffs and reliable change index were calculated. Exploratory and confirmatory factor analyses were used to determine whether items represented a unidimensional construct; IRT examined item properties of this construct., Results: Values for internal consistency, construct validity, convergent and discriminant validity, and structural validity were satisfactory. Responsiveness was high: Cohen's d, 1.48. Caseness cutoff and reliable clinical change scores were 6.41 and 4.63, respectively. IRT analysis confirmed that item scores possess strong properties in assessing the underlying trait measured by PSYCHLOPS., Conclusion: PSYCHLOPS met the criteria for norm-referenced measurement of patient psychological distress. PSYCHLOPS functioned as a measure of a single latent trait, which we describe as "personal distress.", (© 2021 Wiley Periodicals LLC.)

Background: There have been two kinds of methods for assessing individuals' motivation and their goal-striving behavior. The idiographic method obtains respondents' individual descriptions of their behavior or inner experiences. The nomothetic approach uses a standardized questionnaire in which respondents select from a set of alternatives. Idiographic responses provide rich, individualized information, but they make comparisons across different individuals difficult. By contrast, the nomothetic approach loses valuable individualized information, but it readily lends itself to cross-individual comparisons., Objective: The present authors have developed a family of motivational assessment instruments within the framework of the Goal Theory of Current Concerns and individuals' goal pursuits. Each of these instruments is a hybrid version of the idiographic and nomothetic methods. Each one obtains individualized information about each respondent at the start of the assessment, but it then utilizes rating scales that allow comparisons across different individuals to be made. The objective of the present article is to present this family of hybridized instruments for potential use in routine outcome monitoring., Method: The method used in this article was to review the development of this family of hybrid assessments instruments over the preceding decades and the research on their psychometric properties and clinical applications. These hybrid tools include the Interview Questionnaire, Work Concerns Inventory, Motivational Structure Questionnaire, and Personal Concerns Inventory and their variants. The review includes only the idiographic-nomothetic approaches that are based on the Goal Theory of Current Concerns., Results: The review reveals that for each instrument, motivational indices are calculated, which have been shown to be valid and reliable. Analyses have also revealed adaptive and maladaptive motivational factors., Conclusions: The measures discussed here have proven useful in clinical applications, when, for example, they are used as components of Systematic Motivational Counseling and the Life Enhancement and Advancement Programme for helping individuals improve their motivational structure. Similarly, the measures hold promise for use in routine outcome monitoring., (© 2021 Wiley Periodicals LLC.)

The aim of this paper is to report our notes from the field on using movement toward goals at an aggregate level as an inference of service effectiveness. Analysis of routinely collected data from UK youth mental health services was conducted (N = 8,172, age M = 13.8, 67% female, 32% male) to explore the impact of including goal-based outcome data in combined calculations of standardized measures based on the principles of reliable change ("measurable change"). Due to the broad nature of standardized measures, inferred validity becomes diluted in any team or service level aggregate analysis. To make inferences that are closer to the person's interpretation of their difficulties, we argue that Idiographic Patient Reported Outcome Measures (I-PROMs) counterbalance these limitations. This is supported by our findings. The measurable change metric is the first step towards enabling national analysis of aggregated I-PROMs. I-PROMs, supplemented by standardized measures should be used to consider service evaluation., (© 2021 Wiley Periodicals LLC.)

Objective: This study aimed to assess the reliability, validity, and clinical utility of an idiographic, goal-focused patient-reported outcome measure: The Goals Form., Methods: Data were analyzed from 88 participants, across three samples, who had participated in collaborative-integrative psychotherapy at university-based clinics in the UK. The samples were approximately 70% female with mean age of 30 years old., Results: The psychometric properties of the Goals Form were generally good. Noncompletion of individual items was low, temporal stability tended to be at target levels, and mean change scores showed moderate to good convergent validity against measures of psychological distress. The measure appeared sensitive to change in psychotherapy and was experienced by most patients as helpful., Conclusions: The Goals Form shows acceptable psychometric and clinical properties for routine outcome monitoring in psychotherapy., (© 2022 The Authors. Journal of Clinical Psychology published by Wiley Periodicals LLC.)

Background: Prevention of binge eating through just-in-time mobile interventions requires the prediction of respective high-risk times, for example, through preceding affective states or associated contexts. However, these factors and states are highly idiographic; thus, prediction models based on averages across individuals often fail., Objective: We developed an idiographic, within-individual binge-eating prediction approach based on ecological momentary assessment (EMA) data., Methods: We first derived a novel EMA-item set that covers a broad set of potential idiographic binge-eating antecedents from literature and an eating disorder focus group (n=11). The final EMA-item set (6 prompts per day for 14 days) was assessed in female patients with bulimia nervosa or binge-eating disorder. We used a correlation-based machine learning approach (Best Items Scale that is Cross-validated, Unit-weighted, Informative, and Transparent) to select parsimonious, idiographic item subsets and predict binge-eating occurrence from EMA data (32 items assessing antecedent contextual and affective states and 12 time-derived predictors)., Results: On average 67.3 (SD 13.4; range 43-84) EMA observations were analyzed within participants (n=13). The derived item subsets predicted binge-eating episodes with high accuracy on average (mean area under the curve 0.80, SD 0.15; mean 95% CI 0.63-0.95; mean specificity 0.87, SD 0.08; mean sensitivity 0.79, SD 0.19; mean maximum reliability of r D 0.40, SD 0.13; and mean r CV 0.13, SD 0.31). Across patients, highly heterogeneous predictor sets of varying sizes (mean 7.31, SD 1.49; range 5-9 predictors) were chosen for the respective best prediction models., Conclusions: Predicting binge-eating episodes from psychological and contextual states seems feasible and accurate, but the predictor sets are highly idiographic. This has practical implications for mobile health and just-in-time adaptive interventions. Furthermore, current theories around binge eating need to account for this high between-person variability and broaden the scope of potential antecedent factors. Ultimately, a radical shift from purely nomothetic models to idiographic prediction models and theories is required., (©Ann-Kathrin Arend, Tim Kaiser, Björn Pannicke, Julia Reichenberger, Silke Naab, Ulrich Voderholzer, Jens Blechert. Originally published in JMIR Medical Informatics (https://medinform.jmir.org), 23.02.2023.)

Background: Despite public knowledge of the adverse health effects of tobacco use, cigarettes remain widely used due to the addictive nature of nicotine. Physiologic adaptation to the presence of nicotine over time leads to unpleasant effects during withdrawal periods. Alongside these physiological effects, tobacco users often report changes in their consumption of tobacco in response to their emotional state. Objectives: We hypothesized that idiographic, or person-specific level, increases in participants' negative affect (NA) and positive affect (PA) ratings at a given time point would be associated with higher and lower craving and smoking over the following several hours, respectively. Fifty-two participants completed block randomized ecological momentary assessment surveys on their smartphones 4 times per day for 30 days, reporting from 0-100 their level of seven discrete emotions, stress, current craving, and smoking behavior. We analyzed the relationships between affect and smoking and craving using idiographic generalized linear models. Results: While some participants exhibited the hypothesized relationships, each participant varied in the strength and direction of the relationships between affect and craving/smoking. These outcomes were partially moderated at the group level by anxiety/depression at baseline, but not by level of nicotine dependence or sex. Conclusions: This suggests that the factors driving cigarette use vary significantly between individuals.

A longstanding goal of psychology is to predict the things that people do and feel, but tools to accurately predict future behaviors and experiences remain elusive. In the present study, we used intensive longitudinal data ( N = 104 college-age adults at a midwestern university; total assessments = 5,971) and three machine-learning approaches to investigate the degree to which three future behaviors and experiences-loneliness, procrastination, and studying-could be predicted from past psychological (i.e., personality and affective states), situational (i.e., objective situations and psychological situation cues), and time (i.e., trends, diurnal cycles, time of day, and day of the week) phenomena from an idiographic, person-specific perspective. Rather than pitting persons against situations, such an approach allows psychological phenomena, situations, and time to jointly predict future behaviors and experiences. We found (a) a striking degree of prediction accuracy across participants, (b) that a majority of participants' future behaviors are predicted by both person and situation features, and (c) that the most important features vary greatly across people.

Background: Ecological momentary assessment (EMA) studies have provided conflicting evidence for the mood regulation tenet that people drink in response to positive and negative moods. The current study examined mood-to-alcohol relationships idiographically to quantify the prevalence and intensity of relationships between positive and negative moods and drinking across individuals., Method: We used two EMA samples: 96 heavy drinking college students (sample 1) and 19 young adults completing an ecological momentary intervention (EMI) for drinking to cope (sample 2). Mood and alcohol use were measured multiple times per day for 4-6 weeks. Mood-alcohol relationships were examined using three different analytic approaches: standard multilevel modeling, group causal modeling, and idiographic causal modeling., Results: Both multilevel modeling and group causal modeling showed that participants in both samples drank in response to positive moods only. However, idiographic causal analyses revealed that only 63% and 21% of subjects (in samples 1 and 2, respectively) drank following any positive mood. Many subjects (24% and 58%) did not drink in response to either positive or negative mood in their daily lives, and very few (5% and 16%) drank in response to negative moods throughout the EMA protocol, despite sample 2 being selected specifically because they endorse drinking to cope with negative mood., Conclusion: Traditional group-level analyses and corresponding population-wide theories assume relative homogeneity within populations in mood-alcohol relationships, but this nomothetic approach failed to characterize accurately the relationship between mood and alcohol use in approximately half of the subjects in two samples that were demographically and clinically homogeneous. Given inconsistent findings in the mood-alcohol relationships to date, we conclude that idiographic causal analyses can provide a foundation for more accurate theories of mood and alcohol use. In addition, idiographic causal models may also help improve psychosocial treatments through direct use in clinical settings., (© 2022 The Authors. Alcoholism: Clinical & Experimental Research published by Wiley Periodicals LLC on behalf of Research Society on Alcoholism.)

Objective : Measurement-based care (MBC), which encompasses routine outcome monitoring (ROM) and measurement feedback systems (MFSs), is an evidence-based practice (EBP) supporting treatment personalization and clinical responsiveness. Despite MBC's effectiveness, clinicians report reservations regarding its utility, which may be a function of overreliance on nomothetic (i.e., standardized) measures. Although research suggests that individualized (i.e., idiographic) patient-reported outcome measures (I-PROMs) may have the potential to overcome these obstacles, little is known regarding clinicians' perceptions of different measurement approaches to MBC. Methods : This study examined clinicians' perceptions of the clinical utility, relevance to treatment planning, and practicality of nomothetic, individualized, and combined clinical feedback provided by a simulated MFS. Three hundred and twenty-nine clinicians were randomized to one of three conditions that presented a clinical vignette comprising: (a) nomothetic, (b) individualized, or (c) combined clinical feedback. Results : Participants' perceptions of the clinical feedback were not affected by the measurement approach. However, cognitive behavioral participants reported more positive perceptions of all aspects associated with the clinical feedback. Conclusion : These results were consistent with previous findings, suggesting that clinicians' theoretical orientation may have a significant impact on their perceptions of MBC, and should be considered when designing and implementing these systems.

Background: Comorbidity between depression and cognitive impairment is common in older adults, increases the disease burden disproportionally, and leads to diagnostic uncertainty. Insight into individual daily associations between affect and cognitive performance may help in personalizing diagnosis and treatment decisions. Our objective was to get insight into the daily associations between affect and cognitive performance within individual older adults., Methods: In this single-subject study seven older adults with both depression and cognitive impairment filled in electronic diaries daily for 62-93 consecutive days evaluating positive affect (PA), negative affect (NA), working memory (WM) and visual learning (VL). Time-series analyses using vector autoregressive modelling, Granger causality tests and cumulative orthogonalized impulse response function analyses were performed for each individual separately., Results: In one patient higher NA was associated with better WM the next day. For another patient days with higher NA and lower PA were days with worse WM. For a third patient better VL was associated with lower NA and higher PA the next day. No associations were found for four patients., Conclusions: These results highlight heterogeneity in the daily associations between affect and cognitive performance and stress the relevance of single-subject studies. These studies may be an important step towards personalized diagnosis and treatment in old age psychiatry., (© 2022. The Author(s).)

Exposure therapy works through inhibitory learning, whereby patients are exposed to stimuli that elicit anxiety in order to establish safety associations. Mindful emotion awareness, or nonjudgmental and present-focused attention toward emotions, may facilitate engagement in exposures, which may in turn enhance therapeutic outcome. This study utilizes a single-case experimental design ( n = 6) to investigate the effect of mindful emotion awareness training on the use of avoidant strategies during exposures, distress during exposures, overall mindfulness, experiential avoidance, and symptom reduction in a sample of participants with social anxiety disorder. Data were analyzed using a combination of visual inspection and quantitative effect size metrics commonly applied in single-case experimental designs. To further investigate the relationship between distress and avoidant strategy use, contemporaneous and cross-lagged correlations were run. Results highlight individual differences in responses to mindful emotion awareness training and exposure exercises. Given these individual differences, repeated assessment and monitoring over the course of treatment may help clinicians most effectively identify treatment skills that will be most helpful for individual patients.

Objectives: To investigate the presence, nature and direction of the daily temporal association between depressive symptoms, cognitive performance and sleep in older individuals., Design, Setting, Participants: Single-subject study design in eight older adults with cognitive impairments and depressive symptoms., Measurements: For 63 consecutive days, depressive symptoms, working memory performance and night-time sleep duration were daily assessed with an electronic diary and actigraphy. The temporal associations of depressive symptoms, working memory and total sleep time were evaluated for each participant separately with time-series analysis (vector autoregressive modeling)., Results: For seven out of eight participants we found a temporal association between depressive symptoms and/or sleep and/or working memory performance. More depressive symptoms were preceded by longer sleep duration in one person (r = 0.39; p < .001), by longer or shorter sleep duration than usual in one other person (B = 0.49; p < .001), by worse working memory in one person (B = -0.45; p = .007), and by better working memory performance in one other person (B = 0.35; p = .009). Worse working memory performance was preceded by longer sleep duration (r = -.35; p = .005) in one person, by shorter or longer sleep duration in three other persons (B = -0.76; p = .005, B = -0.61; p < .001; B = -0.34; p = .002), and by more depressive symptoms in one person (B = -0.25; p = .009)., Conclusion: The presence, nature and direction of the temporal associations between depressive symptoms, cognitive performance and sleep differed between individuals. Knowledge of personal temporal associations may be valuable for the development of personalized intervention strategies in order to maintain their health, quality of life, functional outcomes and independence.

Objective: While the overlap between personality and psychopathology is well documented, few studies examine how the two overlap at a lower, moment-to-moment level. We took an idiographic approach to examine personality and psychopathology processes at the individual level. Doing so offers a unique perspective by incorporating both dynamic time and structural analysis, two components that are traditionally examined separately when investigating the overlap between personality and psychopathology., Method: Two experience sample studies measured personality states and personality problems up to four-times a day over a two-week period (Study 1 N = 349, observations = 11,124; Study 2 N = 161, observations = 8,261)., Results: For some, personality states and personality problems are deeply intertwined, mirroring existing between-person findings. But for others the two are separate, indicating it is possible to separate personality (states) from a person's problems. Between-person differences in levels of depression had no association with the idiographic structure, indicating that between-person constructs operate separately from within-person processes. Finally, situations that are more likely to bring out personality problems did not alter the association between personality states and personality problems., Conclusions: This method provides a novel conceptualization of personality-psychopathology overlap, bringing the focus beyond mostly static, between-person models to more dynamic, individual-level models., (© 2021 Wiley Periodicals LLC.)

Abstract Idiographic, or individual-level, methodology has been touted for its potential clinical utility. Empirically modeling relationships between symptoms for a single individual may offer both the client and therapist information that is useful for case conceptualization and treatment planning. However, few studies have investigated the feasibility and utility of integrating idiographic models in a clinical setting. Introduction: Idiographic, or individual-level, methodology has been touted for its potential clinical utility. Empirically modeling relationships between symptoms for a single individual may offer both the client and therapist information that is useful for case conceptualization and treatment planning. However, few studies have investigated the feasibility and utility of integrating idiographic models in a clinical setting. Methods: Clients ( n =  Results indicated that the idiographic model structures varied widely across participants and differed markedly from the client's own predictions. Clients found the models useful, whereas their therapists demonstrated a more tempered response. Results: These results echo previous findings suggesting that clients are willing to complete intensive data collection and are interested in the output, whereas therapists may be less open to idiographic methods. We provide recommendations for future implementation of personalized models in clinical settings.Discussion: These results echo previous findings suggesting that clients are willing to complete intensive data collection and are interested in the output, whereas therapists may be less open to idiographic methods. We provide recommendations for future implementation of personalized models in clinical settings.

Precision health initiatives aim to progressively move from traditional, group-level approaches to health diagnostics and treatments toward ones that are individualized, contextualized, and timely. This article aims to provide an overview of key methods and approaches that can help facilitate this transition in the health behavior change domain. This article is a narrative review of the methods used to observe and change complex health behaviors. On the basis of the available literature, we argue that health behavior change researchers should progressively transition from (i) low- to high-resolution behavioral assessments, (ii) group-only to group- and individual-level statistical inference, (iii) narrative theoretical models to dynamic computational models, and (iv) static to adaptive and continuous tuning interventions. Rather than providing an exhaustive and technical presentation of each method and approach, this article articulates why and how researchers interested in health behavior change can apply these innovative methods. Practical examples contributing to these efforts are presented. If successfully adopted and implemented, the four propositions in this article have the potential to greatly improve our public health and behavior change practices in the near future., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Society of Behavioral Medicine.)

According to Zagaria et al. (2020), evolutionary psychology may be the meta-theory that is needed if psychological science is to enter a paradigmatic stage. Other writers have suggested that what is needed is a person-oriented approach, which focuses on the person as a complex system that needs to be studied (1) as a whole (holism), (2) as an intentional agent in interaction with its environment (interactionism), and (3) in terms of his or her individual characteristics and development (idiographic focus). The purpose of the present paper is to discuss the compatibility of these two suggestions. A brief analysis of some formulations central to Dawkins' gene-centered approach (e.g., "the intricate interdependence of genes", and the dependence of genes on their environment) suggests that it is quite compatible with holism and interactionism; and applications such as genetic genealogy illustrate the possibility of a person-oriented genetics. It is argued that these two perspectives are not only compatible, but also complementary. Without a complement in the form of a person-oriented perspective, a gene-centered evolutionary psychology will at best be able to produce a general understanding of the psychological potentials that inhere in the human gene pool. It will not, however, lead to any understanding of the unique profiles of psychological potentials that are produced by a re-combination of autosomal DNA at the origin of each specific individual person, and that develop over time in interaction with the environment. The latter requires that the gene-centered view is complemented with a person-oriented approach.

Traditional variable-centered research on executive functions (EFs) often infers intraindividual development using group-based averages. Such a method masks meaningful individuality and involves the fallacy of equating group-level data with person-specific changes. We used an intensive longitudinal design to study idiographic executive function fluctuation among ten boys from Grade 4. Each of the participants completed between 33 and 43 measurement occasions ( M = 38.8) across approximately three months. Data were collected remotely using a computerized short version of the Dimensional Change Card Sort task. Multi-group analyses of three participant pairs (Participants 5 and 3, 5 and 2, and 5 and 6) demonstrated that Participant 5 differed from Participants 3 and 2 in different ways but Participants 5 and 6 were similar in all comparisons. Dynamic structural equation modeling demonstrated unique individual trajectories, which were not represented by the trajectory of group-averages. Although more than half of the participants showed a negative association between EFs and inattention, two participants showed a positive association between EF and inattention. This study demonstrated meaningful person-specific trajectories of EFs, suggesting that future study should undertake the analysis of individual development before data-aggregation or generalization from aggregate statistics to individuals., Competing Interests: All authors declare that there is no conflict of interest., (© Person-Oriented Research.)

Scientific evidence in the field of psychiatry is mainly derived from group-based ("nomothetic") studies that yield group-aggregated results, while often the need is to answer questions that apply to individuals. Particularly in the presence of great inter-individual differences and temporal complexities, information at the individual-person level may be valuable for personalized treatment decisions, individual predictions and diagnostics. The single-subject study design can be used to make inferences about individual persons. Yet, the single-subject study is not often used in the field of psychiatry. We believe that this is because of a lack of awareness of its value rather than a lack of usefulness or feasibility. In the present paper, we aimed to resolve some common misconceptions and beliefs about single-subject studies by discussing some commonly heard "facts and fictions." We also discuss some situations in which the single-subject study is more or less appropriate, and the potential of combining single-subject and group-based study designs into one study. While not intending to plea for single-subject studies at the expense of group-based studies, we hope to increase awareness of the value of single-subject research by informing the reader about several aspects of this design, resolving misunderstanding, and providing references for further reading., (Copyright © 2020 Zuidersma, Riese, Snippe, Booij, Wichers and Bos.)

Mounting evidence suggests that the ability to regulate emotion is crucial for psychological well-being. However, one important limitation of prior emotion regulation studies is that they rely on standardized stimuli low in personal relevance. To address this limitation, the current study employed a novel event-related potential (ERP) paradigm designed to investigate the late positive potential (LPP) as a measure of emotional reactivity and regulation to idiographic stimuli in 49 young adults. The Autobiographical Emotion Regulation Task (AERT) is a word-viewing task in which participants identify neutral and emotionally-charged autobiographical memories and generate keywords unique to each memory. First, participants are instructed to simply view the keywords. Then, participants are presented with keywords from negative memories and are either instructed to react normally (react condition), or to use cognitive reappraisal to decrease negative emotion (reappraise condition). Results indicate that the LPP was potentiated when initially viewing keywords for negative compared to neutral memories. Furthermore, the LPP was reduced during reappraise compared to react trials, demonstrating successful down-regulation of neural activity to negative idiographic stimuli. These findings suggest that the AERT is a feasible and effective probe of emotion regulation to idiographic stimuli., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Objective: Assuming personality to be a system of intra-individual processes emerging over time in interaction with the environment, we propose an idiographic approach to investigate potential changes of intra-individual dynamics in the perception of situations and emotions of individuals varying in personality traits. We compared the semiparametric time-varying autoregressive model (TV-AR) that takes into account the non-stationarity of psychological processes at the individual level, with the standard AR model., Method: We conducted analyses of individual time series to assess intra-individual changes in mean levels and inertia on data from two adolescents who completed measures of personality and indicated their situation perceptions and emotions five times a day for 19 days., Results: For the less honest, emotional, extraverted, and more agreeable adolescent, the TV-AR model detected reliable changes in the intra-individual dynamics of situation perceptions and emotions whereas, for the other individual, the standard AR model was more preferred, given the lack of changes in the intra-individual dynamics., Conclusions: Psychological processes dynamics in situation perception and emotions may vary from person to person depending on their personality. This work constitutes a first step in demonstrating that an idiographic approach has advantages in identifying changes in individuals' perceptions and reactions to situations., (© 2020 Wiley Periodicals, Inc.)

The personalized approach to psychopathology conceptualizes mental disorder as a complex system of contextualized dynamic processes that is nontrivially specific to each individual, and it seeks to develop formal idiographic statistical models to represent these individual processes. Although the personalized approach draws on long-standing influences in clinical psychology, there has been an explosion of research in recent years following the development of intensive longitudinal data capture and statistical techniques that facilitate modeling of the dynamic processes of each individual's pathology. Advances are also making idiographic analyses scalable and generalizable. We review emerging research using the personalized approach in descriptive psychopathology, precision assessment, and treatment selection and tailoring, and we identify future challenges and areas in need of additional research. The personalized approach to psychopathology holds promise to resolve thorny diagnostic issues, generate novel insights, and improve the timing and efficacy of interventions.

Background: There is a strong link between sleep and major depression; however, the causal relationship remains unclear. In particular, it is unknown whether changes in depression core symptoms precede or follow changes in sleep, and whether a longer or shorter sleep duration is related to improvements of depression core symptoms., Objective: The aim of this study was to investigate temporal associations between sleep and depression in patients suffering from major depressive disorder using an idiographic research approach., Methods: Time-series data of daily sleep assessments (time in bed and total sleep time) and self-rated depression core symptoms for an average of 173 days per patient were analyzed in 22 patients diagnosed with recurrent major depressive disorder using a vector autoregression model. Granger causality tests were conducted to test for possible causality. Impulse response analysis and forecast error variance decomposition were performed to quantify the temporal mutual impact of sleep and depression., Results: Overall, 11 positive and 5 negative associations were identified between time in bed/total sleep time and depression core symptoms. Granger analysis showed that time in bed/total sleep time caused depression core symptoms in 9 associations, whereas this temporal order was reversed for the other 7 associations. Most of the variance (10%) concerning depression core symptoms could be explained by time in bed. Changes in sleep or depressive symptoms of 1 SD had the greatest impact on the other variable in the following 2 to 4 days., Conclusions: Longer rather than shorter bedtimes were associated with more depression core symptoms. However, the temporal orders of the associations were heterogeneous., (©Noah Lorenz, Christian Sander, Galina Ivanova, Ulrich Hegerl. Originally published in JMIR Mental Health (http://mental.jmir.org), 23.04.2020.)

Clinical psychological science has seen an exciting shift toward the use of person-specific (idiographic) approaches to studying psychopathology and change in treatment at the level of the individual. One commonly used method in idiographic research is ecological momentary assessment (EMA). EMA offers a way to sample individuals intensively - often multiple times per day - as they go about their lives. While these methods offer benefits such as greater ecological validity and streamlined data collection, many share concerns about their feasibility across diverse clinical populations. To investigate the feasibility of using EMA to study psychological processes idiographically both in- and out of the context of therapy, the present study aggregated participants across seven studies spanning diverse clinical and community populations ( N = 496), all of which utilized an idiographic EMA approach to study symptoms of psychopathology (e.g., PTSD, mood and anxiety, substance abuse). In a series of linear regression models, participant and study design characteristics were used to predict compliance with EMA surveys. Across study designs, we found that (1) participants were willing to report on symptoms and mechanisms relating to a wide range of psychopathological domains; (2) on average, participants completed 82.21% ( SD = 16.34%) of all EMA surveys; and (3) compliance with EMA surveys was not significantly related to participant demographics, psychological diagnosis, personality characteristics, or most study characteristics (e.g., number of surveys per day). These findings suggest feasibility of idiographic EMA for collecting the data needed to understand psychopathology and change in treatment at the level of the individual., Competing Interests: The authors declare that there is no conflict of interest., (© Person-Oriented Research.)

Common conclusions from traditional psychotherapy research are that we still do not know how or why even our most well-studied interventions produce change, and that there is little evidence that any form of psychotherapy is generally more effective than any other. This has led some researchers to the so-called Dodo Bird Verdict, that all forms of psychotherapy are equally effective, and to the conclusion that what is at work are "common factors" that have little to do with treatment method. An alternative explanation, however, is that the traditional research paradigm is insufficiently sensitive to provide us with the required kind of knowledge. First, the outcome in typical RCTs is averaged across individuals, and at best complemented by a search for predictors in the form of stable individual differences. This means that this research stays at a group level of analysis and is insensitive to variation and change in individual patients. Second, the independent variable in RCTs does not consist in any well-controlled psychological intervention, but in large-scale treatment packages that contain a large number of interventions over a considerable time period. In other words, this research is insensitive to the effects of specific treatment interventions. Third, traditional psychotherapy research is insensitive to the therapist and patient as individual persons, and their specific interaction. It is argued that a person-oriented approach to psychotherapy, which is idiographic, holistic and interactional, may be able to overcome some of these problems by being more sensitive to (1) the treatment course of individual patients, and patterns during that course; (2) the effects of the specific interventions that are implemented over time, and (3) the personal characteristics of patient and therapist, and nuances of their interaction., (© Person-Oriented Research.)

Theorists and clinicians have long noted the need for idiographic (i.e., individual-level) designs within clinical psychology. Results from idiographic work may provide a possible resolution of the therapist's dilemma-the problem of treating an individual using information gathered via group-level research. Due to advances in data collection and time series methodology, there has been increasing interest in using idiographic designs to answer clinical questions. Although time series methods have been well-studied outside the field of clinical psychology, there is limited direction on how clinicians can use such models to inform their clinical practice. In this primer, we collate decades of published and word-of-mouth information on idiographic designs, measurement, and modeling. We aim to provide an initial guide on the theoretical and practical considerations that we urge interested clinicians to consider before conducting idiographic work of their own., (Copyright © 2019. Published by Elsevier Ltd.)

High-achieving students face greater expectations in competitive societies such as China, which can impede their performance. Based on previous observations regarding what we call the "inhibition phenomenon of high-achieving students," wherein otherwise successful students show unexpectedly poor performances in collective activities of relatively unfamiliar forms, the present research analyzes the self-identity of such students and explores the underlying mechanisms that result in this inhibition phenomenon. An idiographic approach is employed to examine typical cases and their semiotic mediation in the self-identity regulative process. Two high-achieving students who exhibit the characteristics of the inhibition phenomenon are compared with another high-achieving student who appears not to be inhibited, using a multilevel and comprehensive analysis that integrates a number of aspects, such as the students' emotional experience of the activities in relation to which the inhibition phenomenon occurs, their meaning-making regarding the activities, and their reflections on their daily school lives. The findings show that, for the inhibited students, a cued identity as being a "good student" is activated through the activities with the connotations of "being successful compared to the others" and "pursuing recognition" leading to a worsened performance; alternatively, the student not susceptible to inhibition displays an identity of being a "learner," who focuses on the content of the activity and concrete suggestions from important others. These specific semiotic mediation processes indicate that, when self-identity is narrow and result oriented, it is easy for excessive future-oriented self-demands to be imposed, thereby bringing pressure to the individual at that moment. By contrast, a flexible and process-oriented identity facilitates an individual's involvement in unfamiliar activities, enabling a richer, more open self-construction process.

Researchers have long called for greater recognition and use of longitudinal, individual-level research in the study of psychopathology and psychotherapy. Much of our current research attempts to indirectly investigate individual-level, or idiographic, psychological processes via group-based, or nomothetic, designs. However, results from nomothetic research do not necessarily translate to the individual-level. In this review, we discuss how idiographic analyses can be integrated into psychotherapy and psychotherapy research. We examine and review key statistical methods for conducting idiographic analyses. These methods include factor-based and vector autoregressive approaches using longitudinal data. The theoretical framework behind each approach is reviewed and critically evaluated. Empirical examples of each approach are discussed, with the aim of helping interested readers consider how they may use idiographic methods to analyze longitudinal data and psychological processes. Finally, we conclude by citing key limitations of the idiographic approach, calling for greater development of these analyses to ease their successful integration into clinical settings., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Objective: The aim of this study was to explore the daily relationship between illness uncertainty, avoidance of uncertainty, well-being and treatment-related distress among patients with cancer receiving treatment with curative intent. It was hypothesised that daily illness uncertainty, daily avoidance of uncertainty and daily treatment-related distress would be negatively associated with daily well-being. It was also hypothesised that daily illness uncertainty and daily avoidance of uncertainty would be positively associated with daily treatment-related distress., Design: Thirty-one patients receiving oncology treatment with curative intent completed a daily diary for seven consecutive days. Data were analysed using multilevel modelling., Main Outcome Measures: Daily illness uncertainty, avoidance of illness uncertainty, treatment-related distress and well-being., Results: As hypothesised, on days when patients with cancer reported heightened treatment-related distress they experienced diminished well-being. And on days when patients reported more experiential avoidance of illness uncertainty, they also experienced heightened levels of treatment-related distress. No other daily associations were significant., Conclusion: These findings indicate that patients with cancer experience day-to-day fluctuations in distress and well-being throughout oncology treatment. Avoidance of illness uncertainty-related thoughts and/or emotions are associated with daily distress, but not daily well-being.

Approaches to identifying individuals at clinical high-risk (CHR) for psychosis currently do not carefully weigh considerations around individual differences. Effective identification depends on awareness of factors beyond psychopathology as it is reflected in the current literature, such as sensitivity to idiographic circumstances and individual differences. The inability to address contextual factors when employing the status quo method of identification likely contributes to the unacceptably poor accuracy when identifying people at CHR. Individual differences related to factors such as culture, race, comorbidity, and development likely play an important role in accurate identification, and have the potential to improve the validity of approaches intended to identify this population. Tailored approaches to assessment based on an awareness of context, identity, setting, and preferences of clients are possible, and customizing assessment efforts accordingly may be useful for accurate identification of people at CHR. Highlighting the potential for the existing early identification paradigm to marginalize or misunderstand certain groups, we describe how effective identification and ethical diagnosis require sensitivity to individual differences writ large. We suggest that recognizing the importance of these factors advances a more inclusive and accurate approach to identification.

Introduction: Research indicates that individuals with generalized anxiety disorder (GAD) may experience deficits in positive affect (PA), and tend to dampen or intentionally suppress PA. Despite the presence of PA-related pathology in GAD, little is known about change in PA during GAD treatment., Objective: This study examines changes in PA, negative affect (NA) and worry in seven participants during cognitive behavioral therapy (CBT) for GAD., Method: Intensive repeated measures (i.e., time series) data were subjected to person-specific regression analysis to delineate individual change trajectories., Results: Significant improvement in worry was observed in all but one participant. Fear and irritability - indices of NA - each improved in 5/7 participants while sadness improved in 4/7 participants (worsening in one). Of all symptom domains, PA had the poorest treatment response: PA improved in only 2/7 participants and actually significantly worsened in 5/7 individuals even as NA and worry improved during therapy., Conclusion: These findings indicate that treatment gains from traditional CBT for GAD may not generalize to improvements in PA regulation, or even emotional functioning more broadly. This evidence is a call to increase the focus on PA regulation in treatment for GAD; perhaps PA could be a missing piece in our understanding of ways to bolster GAD treatment outcomes.

Background: Affiliating with 12-step groups appears to reduce relapse risk. By relying on between-person designs, extant research has been unable to examine daily mechanisms through which 12-step group affiliation contributes to recovery., Objectives: To examine the daily use and factor structure of the 12 steps and intrapersonal predictors and moderators of 12-step use. To determine whether the 12 steps were used in response to daily craving and, if so, which steps and in what contexts., Methods: Data comprised 1304 end-of-day diary data entries from 55 young adults collected in 2008 from members of a college recovery community, combined with person-level baseline measures. Exploratory factor analysis examined the factor structure, and multi-level models examined both day-level and person-level predictors and moderators of step use, including meeting attendance, drug and alcohol dependence, social support, and coping strategies., Results: Analyses produced two factors: Everyday steps, comprising surrender and maintenance steps, and action steps. Moderation analyses revealed that only action steps were significantly associated with craving, suggesting that craving can spur their use, but only among individuals pursuing certain general strategies for coping with stress: Separate median-split models produced significant associations between craving and action steps only among individuals high in avoidance, high in support-seeking, and/or low in problem-solving. Conclusions/Importance: This is the first study to empirically discern a 2-factor structure underlying the 12 steps, and to show that the two sets of steps are used in different contexts. The study also illustrates the value of person-centered approaches to recovery research and practice.

Objective: Dichotomizing clinical trials designs into nomothetic (e.g., randomized clinical trials or RCTs) versus idiographic (e.g., N-of-1 or case studies) precludes use of an array of hybrid designs and potential research questions between these extremes. This paper describes unique clinical evidence that can be garnered using idiographic clinical trials (ICTs) to complement RCT data. Proposed and illustrated herein is that innovative combinations of design features from RCTs and ICTs could provide clinicians with far more comprehensive information for testing treatments, conducting pragmatic trials, and making evidence-based clinical decisions., Method: Mixed model trajectory analysis and unified structural equations modeling were coupled with multiple baseline designs in (a) a true N-of-1 pilot study to improve severe autism-related communication deficits and (b) a small sample preliminary study of two complimentary interventions to relieve wheelchair discomfort., Results: Evidence supported certain mechanisms of treatment outcomes and ruled out others. Effect sizes included mean phase differences (i.e., effectiveness), trajectory slopes, and differences in path coefficients between study phases., Conclusions: ICTs can be analyzed with equivalent rigor as, and generate effect sizes comparable to, RCTs for the purpose of developing hybrid designs to augment RCTs for pilot testing innovative treatment, efficacy research on rare diseases or other small populations, quantifying within-person processes, and conducting clinical trials in many situations when RCTs are not feasible., (© Person-Oriented Research.)

The advancement of implementation science is dependent on identifying assessment strategies that can address implementation and clinical outcome variables in ways that are valid, relevant to stakeholders, and scalable. This paper presents a measurement agenda for implementation science that integrates the previously disparate assessment traditions of idiographic and nomothetic approaches. Although idiographic and nomothetic approaches are both used in implementation science, a review of the literature on this topic suggests that their selection can be indiscriminate, driven by convenience, and not explicitly tied to research study design. As a result, they are not typically combined deliberately or effectively. Thoughtful integration may simultaneously enhance both the rigor and relevance of assessments across multiple levels within health service systems. Background on nomothetic and idiographic assessment is provided as well as their potential to support research in implementation science. Drawing from an existing framework, seven structures (of various sequencing and weighting options) and five functions (Convergence, Complementarity, Expansion, Development, Sampling) for integrating conceptually distinct research methods are articulated as they apply to the deliberate, design-driven integration of nomothetic and idiographic assessment approaches. Specific examples and practical guidance are provided to inform research consistent with this framework. Selection and integration of idiographic and nomothetic assessments for implementation science research designs can be improved. The current paper argues for the deliberate application of a clear framework to improve the rigor and relevance of contemporary assessment strategies.

Objectives: Deep brain stimulation (DBS) is a form of biotechnological surgery which has had considerable success for the motor improvement of Parkinson's disease and related disorders. Paradoxically, this observed motor improvement is not matched with improved psychosocial adjustment. This study contributes to a small but growing body of research aiming to understand this paradox. We conclude by discussing these aspects from a phenomenological and health psychology understanding of decision-making, human affectivity, and embodiment., Design: A hermeneutic phenomenological case study., Methods: Semi-structured interviews with one woman with Parkinson's disease were carried out paying particular attention to (1) how the decision to have the procedure was made and (2) the affective experience in the time periods immediately prior to the procedure, shortly after and 1 month later., Results: The thematic structure derived from the hermeneutic phenomenological analysis comprises the following experiential aspects: Making the decision: 'I was feeling rather at a dead end with my Parkinson's'; Shifting emotions and feelings: 'Terrified, excited, disappointed, overjoyed'; Embodied meaning: 'This extraordinary procedure where they were going to drill holes in my head'., Conclusions: This research has elucidated the complexity of decision-making, the emotional landscape, and specific bodily nature of the experience of DBS. It has suggested implications for practice informed by both existential-phenomenological theory and health psychology. Statement of contribution What is already known on this subject? Deep brain stimulation (DBS) is a newly developed form of biotechnological surgery and research indicates a mismatch between motor success and psychosocial adjustment. Most studies focuses on life post-DBS and there is relatively little research on how people make the decision to have the procedure, what their experience is of undergoing it including its emotional aspects. What does this study add? This study demonstrates that making decisions with respect to health and illness is complex and best understood as a form of embodied cognition. Findings indicate that the experience of undergoing DBS surgery is one of multiple emotions, especially fear and feelings of 'unhomelikeness'. This study highlights the relevance of a lifeworld, people-centered and humanizing approach to helping health care professionals support people through an illness/treatment trajectory., (© 2016 The British Psychological Society.)