Within-person Variability Research Articles

Momentary patterns of impulsivity and alcohol use: A cause or consequence?

BackgroundImpulsivity is a robust risk factor for alcohol use, but significant gaps remain in our understanding of the way that impulsivity relates to alcohol harms. Most prior research has been limited to between-level differences; thus, within-person variability in impulsivity at the momentary level and its bidirectional association with alcohol use has not been examined. The present research used a 14-day ecological momentary assessment (EMA) design to determine the bidirectionality of impulsivity and alcohol use and alcohol problems. MethodsParticipants were 89 (47 women) heavy-drinking college students. The mean age was 19.80 (SD = 1.76) years. Participants completed a baseline questionnaire and 14 consecutive days of momentary reports sent in the morning, afternoon, and evening; participants also completed two user-initiated reports during a drinking occasion at the beginning and the end of their drinking. ResultsMultilevel modeling results indicated that greater levels of impulsivity experienced during the day was not associated with alcohol use or problems experienced that night. However, level of alcohol use and the number of alcohol problems experienced predicted greater variability in impulsivity the next day. ConclusionsOverall, this study was the first to examine the bidirectional relationship between impulsivity and alcohol use using EMA. Findings supported impulsivity’s conceptualization as a state construct and fluctuations in alcohol use behaviors coinciding with states of impulsivity the next day after drinking. Findings from the present study contributed to conceptual daily process models of drinking by identifying how alcohol behaviors unfold in the real world.

Changes of cortisol, dehydroepiandrosterone, testosterone, estradiol, and progesterone in hair across pregnancy, with comparison to a non-pregnant reference group

The literature on hormone changes in pregnancy has focused largely on cortisol, and changes in sample average concentrations. Within-person changes and variability in hormone concentrations are less commonly reported, particularly for sex hormones, and especially measured in hair. Using a prospective sample of pregnant women and a non-pregnant comparison group, we examined changes in five steroid hormones in hair. Non-pregnant women were recruited from the same area with parallel procedures and assessment timeline. Participants include 68 women (34 pregnant, average age = 29.14, and 34 non-pregnant; average age = 27.18) who were predominately non-Hispanic White (83%), and above the 2020 poverty line (75%). Pregnant women provided 3cm hair samples and completed questionnaires three times during pregnancy: 1) at 12 weeks, 2) at 26 weeks, and 3) at 38 weeks. Non-pregnant women provided 3cm hair samples and completed questionnaires three times, at baseline, 14 weeks later, and 12 weeks after that to mirror the assessment schedule of the pregnant group. There was clear evidence that progesterone was higher initially and increased dramatically across pregnancy whereas non-pregnant patterns showed no systematic change. There was suggestive evidence that cortisol and estradiol increased over pregnancy and in non-pregnant women similarly across the same time course. There was suggestive evidence that DHEA decreased across pregnancy, particularly early in pregnancy, differently from patterns in non-pregnant women over the same time course. Most importantly, there was substantial variability of hormone concentrations and many different within-person patterns of changes in these hormones over time, with little evidence of systematic change or stability within-individuals. Moving beyond discussing sample averages to including within-person and non-linear changes in studies of hormones-behavior associations during pregnancy is an important future direction for further investigation.

The effect of dual-release versus conventional hydrocortisone on fatigue, measured by ecological momentary assessments

Replicating the physiological cortisol secretion is key in the treatment of glucocorticoid insufficient individuals and optimization may enhance quality of life. The study investigates fatigue measured by ecological momentary assessments in patients treated with conventional hydrocortisone compared with once-daily dual-release hydrocortisone (Plenadren). A 21-week open-label switch pilot trial included 30 patients with adrenal insufficiency due to hypopituitarism. Fatigue was assessed four times daily for 20 days using a momentary item version of the Multidimensional Fatigue Inventory on patients’ usual hydrocortisone regimen. Participants switched treatment to an identical daily dose of Plenadren for 16 weeks where fatigue assessments were repeated. Change in fatigue and diurnal variation of fatigue was analyzed using mixed models for repeated measurements. In four out of five fatigue subscales fatigue was significantly reduced 0.7–1.1 points (scales ranging from 4 to 20), when treated with Plenadren compared with conventional hydrocortisone, corresponding to small effect sizes below the scale-specific minimal important changes. However, 33% of the participants completing the study (9/27) experienced reductions in fatigue above the minimal important change. On Plenadren, we found larger between-person variances and smaller within-person variances. Finally, we identified diurnal fatigue curves for both treatments. The Plenadren-related reduction in fatigue was significant but not necessarily of clinical importance when looking at a group level. However, there was a large interindividual variation in treatment effect, why patients with a large benefit in quality of life should be identified. Future RCTs should be powered to detect the effect magnitudes identified here.

Levels and volatility in daily relationship quality: Roles of daily sacrifice motives

Conflicts are inevitable in romantic relationships. Couples sometimes choose the pro-relationship strategy of relational sacrifice to address such conflicts. Previous research established that examining sacrifice motives (i.e., approach and avoidance) is meaningful in understanding relationship quality. Using interdependence theory and 14 days of diaries with 110 heterosexual couples, we extend previous research by testing how sacrifice motives predicted both mean levels and volatility of daily relationship quality (i.e., satisfaction, commitment, intimacy, passion, trust, and love). Specifically, we examined actor and partner reports of sacrifice motives as individuals’ average levels (trait; between-person differences) and daily levels of sacrifice motives on a specific day (state; within-person differences) in predicting relationship quality. When predicting mean levels of relationship quality, individuals’ own (actor) trait and state approach and avoidance motives predicted most relationship quality variables. Results were less robust for partner effects, especially for partner trait and state approach motives. When predicting volatility (within-person variability across 14 days) in relationship quality, patterns were more robust for both approach and avoidant motives and for both actor and partner effects. For approach sacrifices, and for all six relationship quality variables, individuals’ trait approach motives predicted lower volatility, whereas avoidance motives predicted higher volatility. For partner effects, individuals reported lower volatility in satisfaction, intimacy, passion, and trust when their partners were higher in approach motives, whereas they reported higher volatility in satisfaction, commitment, intimacy, and trust when their partners were higher in avoidance motives. We discuss the importance of studying dyads and testing the associations between sacrifice motives and daily relationship quality—both levels and volatility.

Insights from computational models of face recognition: A reply to Blauch, Behrmann and Plaut

We agree with Blauch, Behrmann, and Plaut (2020) on a number of points, and are reassured that their data bear out our previous findings. We discuss differences in modelling style, and the usefulness of different types of model for supporting psychological understanding. We emphasise the role that within-person variability plays in recognising familiar faces and clarify the range over which it is idiosyncratic. The combination of image analysis with top-down support to cohere different images of the same person seems to be an important characteristic of successful models.

Continuous Glucose Monitoring and Use of Alternative Markers To Assess Glycemia in Chronic Kidney Disease.

In chronic kidney disease, glycated albumin and fructosamine have been postulated to be better biomarkers of glycemic control than HbA1c. We evaluated the accuracy, variability, and covariate bias of three biomarkers (HbA1c, glycated albumin, and fructosamine) compared with continuous glucose monitoring (CGM)-derived measurement of glycemia across estimated glomerular filtration rate (eGFR) in type 2 diabetes. A prospective cohort study was conducted of 104 participants with type 2 diabetes, 80 with eGFR <60 mL/min/1.73 m2 (not treated with dialysis) and 24 frequency-matched control subjects with eGFR ≥60 mL/min/1.73 m2. Participants wore a blinded CGM for two 6-day periods separated by 2 weeks, with blood and urine collected at the end of each CGM period. HbA1c, glycated albumin, and fructosamine were measured by high-performance liquid chromatographic, enzymatic, and colorimetric nitroblue tetrazolium methods, respectively. Within-person biomarker values were strongly correlated between the two CGM periods (r = 0.92-0.95), although no marker fully captured the within-person variability of mean CGM glucose. All markers were similarly correlated with mean CGM glucose (r = 0.71-77). Compared with mean CGM glucose, glycated albumin and fructosamine were significantly biased by age, BMI, serum iron concentration, transferrin saturation, and albuminuria; HbA1c was underestimated in those with albuminuria. Glycated albumin and fructosamine were not less variable than HbA1c at a given mean CGM glucose level, with several additional sources of bias. These results support measuring HbA1c to monitor trends in glycemia among patients with eGFR <60 mL/min/1.73 m2. Direct measurements of glucose are necessary to capture short-term variability.

The potential for overdiagnosis and underdiagnosis because of blood pressure variability: a comparison of the 2017 ACC/AHA, 2018 ESC/ESH and 2019 NICE hypertension guidelines.

Objective:To estimate the extent that BP measurement variability may drive over- and underdiagnosis of ‘hypertension’ when measurements are made according to current guidelines.Methods:Using data from the National Health and Nutrition Examination Survey and empirical estimates of within-person variability, we simulated annual SBP measurement sets for 1 000 000 patients over 5 years. For each measurement set, we used an average of multiple readings, as recommended by guidelines.Results:The mean true SBP for the simulated population was 118.8 mmHg with a standard deviation of 17.5 mmHg. The proportion overdiagnosed with ‘hypertension’ after five sets of office or nonoffice measurements using the 2017 American College of Cardiology guideline was 3–5% for people with a true SBP less than 120 mmHg, and 65–72% for people with a true SBP 120–130 mmHg. These proportions were less than 1% and 14–33% using the 2018 European Society of Hypertension and 2019 National Institute for Health and Care Excellence guidelines (true SBP <120 and 120–130 mmHg, respectively). The proportion underdiagnosed with ‘hypertension’ was less than 3% for people with true SBP at least 140 mmHg after one set of office or nonoffice measurements using the 2017 American College of Cardiology guideline, and less than 18% using the other two guidelines.Conclusion:More people are at risk of overdiagnosis under the 2017 American College of Cardiology guideline than the other two guidelines, even if nonoffice measurements are used. Making clinical decisions about cardiovascular prediction based primarily on absolute risk, minimizes the impact of blood pressure variability on overdiagnosis.

Intraindividual variability in identity centrality: Examining the dynamics of perceived role progress and state identity centrality.

Conventionally, identity centrality has been conceived of as a stable and transsituational construct, with situational variability in identity centrality treated as being of little informational value. In contrast to past research, we develop a theoretical model arguing that a portion of within-person variability in identity centrality is systematic and meaningful. Drawing on identity control theory, we examine the within-person relationship flowing from perceived role progress to state identity centrality, which is conventionally viewed as reverse causal at the between-person level. We further explain the intermittent effect of an intense positive emotion-passion for the role-and investigate the contingent effect of in-role effort. The results from 2 repeated-measures studies showed that a significant proportion of total variance in identity centrality occurred at the within-person level and perceived role progress influenced state identity centrality by engendering passion for the role contingent on in-role effort. We discuss the theoretical and practical implications of our findings for management and organizations to inspire new intellectual debate and novel viewpoints to advance the microfoundation of identity theory. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Capturing life and its fluctuations: Experience sampling and daily diary studies in studying within-person variability

Capturing life and its fluctuations: Experience sampling and daily diary studies in studying within-person variability

Discretionary Performance in the 21st Century Workplace: Expanding Theory, Research, and Practice

This symposium broadens our sight by expanding theory, research and practice of discretionary performance: organizational citizenship behaviors (OCBs) and counterproductive work behaviors (CWBs; or deviance), which are important components of job performance. The papers in the symposium present new theoretical directions and ways to conceptualize and study these behaviors. These include utilizing a person-centered approach to study profiles (rather than separate traits or behaviors). Specifically, the first paper studies how personality profiles (i.e., combinations of traits) predict discretionary behaviors. The second paper identifies deviance profiles and examines how they relate to traditional antecedents of deviance in non-traditional ways. The third paper examines how between- and within-person variance in CWBs depends on the total study duration and the time intervals between measurements. The second focus of this symposium is on discretionary behaviors in the context of the modern day workplace, thus expanding our understanding of the role that these behaviors play in aligning individual and organizational values in this dynamic environment. Specifically, the fourth paper examines how the interface (i.e., conflict vs. enhancement) between a gig-work identity and an environmental identity affects positive and negative discretionary behaviors. Finally, the fifth paper studies the effects of employee promotive and prohibitive voice on empowering leadership, and how this effect depends on a dynamic work environment. In sum, the papers in this symposium have implications for theory, research and practice in organizational behavior and human resources, as the papers enrich our understanding of attributes and processes related to job performance. Personality Profiles as Predictors of Job Performance: A Person-Centered Approach Presenter: Peng Zhao; Indiana U. - Kelley School of Business Presenter: Christopher M. Berry; Indiana U. - Kelley School of Business The Profiles of Workplace Deviance: A Latent Class Analysis Approach Presenter: Jason Kautz; U. of South Carolina Presenter: Bailey A. Bigelow; U. of Central Florida Presenter: Nichelle Carpenter; U. of South Carolina An Examination of Temporal Variability in CWB Presenter: Casey Giordano; U. of Minnesota Presenter: Brittany Kathleen Mercado; Elon U. Presenter: Deniz S Ones; U. of Minnesota Presenter: Stephan Dilchert; City U. of New York, Baruch College The Effects of Environmental and Work Identities on Discretionary Performance in Gig Economy Work Presenter: Maria Rotundo; U. of Toronto Presenter: Ravit Hezkiau-Ludwig; U. of Toronto Presenter: Chloe Kovacheff; U. of Toronto Presenter: Joyce He; U. of Toronto Fostering Manager’s Trust in Employees: When and Why Does Employee Voice Lead to More Empowerment? Presenter: Shuqi Li; Eli Broad School of Business, Michigan State U. Presenter: Yao Wang; Renmin U. of China Presenter: Russell Eric Johnson; Eli Broad School of Business, Michigan State U.

Effect Direction Between Work-Family Conflict and Psychological Strain: A Replication and Extension

Research on the relationship between work-family conflict (WFC) and psychological strain provides largely inconsistent results about the direction of this effect. To identify a source of this variation, we review modeling approaches used in 15 studies derived from the only meta analytical test of the direction of this effect (Nohe et al., 2015), and 51 newer studies not yet included in this test. We find that none of these studies accounts for the confounding effect of unmeasured, trait-like between-person differences, for example, by adding random intercepts (RIs) to the structural model. Instead, they apply approaches that combine the within-person variance and the between-person variance (e.g., Crossed-Lagged Panel Model, CLPM), thereby leading to biased effect estimates. Recent methodological reviews have thus urged scholars to apply the RI-CLPM to solve this problem. Following these calls, our study replicates and extends prior research by modeling the effect of interest using the CLPM and the RI-CLPM. We seek to examine whether Nohe et al.’s (2015) result holds once the RI-CLPM is applied. We collected three-wave survey data from 12’241 working adults living in Germany. The data are representative of the German workforce and were collected annually from 2016 until 2018. The RI-CLPM yields a significantly better model fit than the CLPM. Whereas the results from our CLPM replicate the meta-analytical finding (i.e., WFC and psychological strain affect each other reciprocally), the RI-CLPM yields a different result: WFC leads to greater psychological strain and not vice versa. Implications for theory development and practice are discussed.

Eight items of the ruminative response scale are sufficient to measure weekly within-person variation in rumination

The Ruminative Response Scale (RRS) is commonly used to measure people’s general tendency to ruminate. In this study, we explored whether only few items from the RRS can be used to capture within-person variation in rumination in intensive longitudinal studies. Such a short RRS version would allow, for example, monitoring the development of rumination during clinical interventions. We measured rumination on five occasions, with at least one week in between. We used multilevel analyses to analyze the data at the within- and between-person level. Using only eight RRS items, we successfully modeled a reflective self-regulation and depressive brooding factor, similar to the two subfacets of rumination as distinguished by Treynor et al. (2003). We also established convergent validity of depressive brooding at the within- and between-person level of analysis and convergent validity of reflection at the between-person level. We thus introduced a short form of the RRS that captures within-person variation in depressive brooding and reflection well. The short RRS is readily applicable in studies on within-person variation or change in rumination.

Prevalence of inadequate and excessive iodine intake in a US pregnancy cohort

US iodine intake, estimated from the median urinary iodine concentration of population representative data, has declined by half since the 1970s, which is problematic because maternal iodine intake is critical for fetal neurodevelopment. Relying on median urinary concentrations to assess iodine intake of populations is standard practice but does not describe the number of individuals with insufficient intake. Prevalence estimates of inadequate and excessive intake are better for informing public health applications but require multiple urine samples per person; such estimates have been generated in pediatric populations but not yet among pregnant women. Our aims were as follows: (1) to assess median urinary iodine concentrations across pregnancy for comparison with national data and (2) to estimate the prevalence of inadequate and excessive iodine intake among pregnant women in mid-Michigan. Data were collected from 2008 to 2015 as part of a prospective pregnancy cohort in which women were enrolled at their first prenatal clinic visit. Few exclusion criteria (<18 years or non-English speaking) resulted in a sample of women generally representative of the local community, unselected for any specific health conditions. Urine specimens were obtained as close as practicable to at least 1 specimen per trimester during routine prenatal care throughout pregnancy (n=1-6 specimens per woman) and stored at -80°C until urinary iodine was measured to estimate the iodine intake (n=1014 specimens from 464 women). We assessed urinary iodine across pregnancy by each gestational week of pregnancy and by trimester. We used multiple urine specimens per woman, accounted for within-person variability, performed data transformation to approximate normality, and estimated the prevalence of inadequate and excessive iodine intake using a method commonly employed for assessment of nutrient status. Maternal characteristics reflected the local population in racial and ethnic diversity and socioeconomic status as follows: 53% non-Hispanic white, 22% non-Hispanic black, and 16% Hispanic; 48% had less than or equal to high school education and 71% had an annual income of <$25,000. Median urinary iodine concentrations in the first, second, and third trimester-including some women contributing more than 1 specimen per trimester-were 171 μg/L (n=305 specimens), 181 μg/L (n=366 specimens), and 179 μg/L (n=343 specimens), respectively, with no significant difference by trimester (P=.50, Kruskal-Wallis test for equality of medians). The estimated prevalence of inadequate and excessive iodine intake was 23% and <1%, respectively. Median urinary iodine concentrations in each trimester were above the World Health Organization cutoff of 150 μg/L, indicating iodine sufficiency at the group level across pregnancy. However, the estimated prevalence of inadequate iodine intake was substantial at 23%, whereas prevalence of excessive intake was <1%, indicating a need for at least some women to increase consumption of iodine during pregnancy. The American Thyroid Association, the Endocrine Society, and the American Academy of Pediatrics recommend that all pregnant and lactating women receive a daily multivitamin or mineral supplement that contains 150 μg of iodine. The data presented here should encourage the collection of similar data from additional US population samples for the purpose of informing the American College of Obstetricians and Gynecologists' own potential recommendations for prenatal iodine supplementation.

Sleep, self-management, neurocognitive function, and glycemia in emerging adults with Type 1 diabetes mellitus: A research protocol.

Type 1 Diabetes (T1D) affects 1.6 million Americans, and only 14% of emerging adults ages 18-25 years achieve targets for glycemic control (A1C < 7.0%). Sleep deficiency, including habitual short sleep duration (<6.5 hr total sleep time and high within-person variability in total sleep time), is associated with poorer glycemic control. Emerging adults with T1D have a more pronounced sleep extension on weekends compared with matched controls, consistent with sleep deficiency; however, associations among sleep variability and glycemic control have not been explored in this population. Sleep deficiency may affect the complex higher-order neurocognitive functioning needed for successful diabetes self-management (DSM). We report the protocol for an ongoing study designed to characterize sleep and the associations among sleep deficiency, neurocognitive function, DSM, diabetes quality of life, and glycemia among a sample of 40 emerging adults with T1D. We monitor sleep via wrist-worn actigraphy and glucose via continuous glucose monitoring concurrently over 14 days. We are collecting data on self-report and objective sleep, a 10-min psychomotor vigilance test on a PVT-192 device, a 3-min Trail Making Test on paper, and questionnaires, including twice-daily Pittsburgh sleep diaries using Research Electronic Data Capture (REDCap)TM . Results from this study will be used to support the development and testing of the efficacy of a tailored sleep self-management intervention that may improve total sleep time, sleep variability, neurocognitive function, DSM, glycemic control, and glucose variability among emerging adults with T1D.

Usability and Acceptability of a Smartphone App to Assess Partner Communication, Closeness, Mood, and Relationship Satisfaction: Mixed Methods Study.

BackgroundInterpersonal communication is critical for a healthy romantic relationship. Emotional disclosure, coupled with perceived partner responsiveness, fosters closeness and adjustment (better mood and relationship satisfaction). On the contrary, holding back from disclosure is associated with increased distress and decreased relationship satisfaction. Prior studies assessing these constructs have been cross-sectional and have utilized global retrospective reports of communication. In addition, studies assessing holding back or perceived partner responsiveness have not taken advantage of smartphone ownership for data collection and have instead required website access or use of a study-provided device.ObjectiveThis study aimed to examine the (1) usability and acceptability of a smartphone app designed to assess partner communication, closeness, mood, and relationship satisfaction over 14 days and (2) between-person versus within-person variability of key constructs to inform the utility of their capture via ecological momentary assessment using the participants’ own handheld devices.MethodsAdult community volunteers in a married or cohabiting partnered relationship received 2 smartphone prompts per day, one in the afternoon and one in the evening, for 14 days. In each prompt, participants were asked whether they had conversed with their partner either since awakening (afternoon prompt) or since the last assessment (evening prompt). If yes, a series of items assessed enacted communication, perceived partner communication, closeness, mood, and relationship satisfaction (evening only). Participants were interviewed by phone, 1 week after the end of the 14-day phase, to assess perceptions of the app. Content analysis was employed to identify key themes.ResultsParticipants (N=27; mean age 36, SD 12 years; 24/27, 89% female; 25/27, 93% white and 2/27, 7% Hispanic) responded to 79.2% (555/701) of the total prompts sent and completed 553 (78.9%) of those assessments. Of the responded prompts, 79.3% (440/555) were characterized by a report of having conversed with one’s partner. The app was seen as highly convenient (mean 4.15, SD 0.78, scale: 1-5) and easy to use (mean 4.39, SD 0.70, scale: 1-5). Qualitative analyses indicated that participants found the app generally easy to navigate, but the response window too short (45 min) and the random nature of receiving notifications vexing. With regard to the variability of the app-delivered items, intraclass correlation coefficients were generally <0.40, indicating that the majority of the variability in each measure was at the within-person level. Notable exceptions were enacted disclosure and relationship satisfaction.ConclusionsThe findings of this study support the usability and acceptability of the app, with valuable user input to modify timing windows in future work. The findings also underscore the utility of an intensive repeated-measures approach, given the meaningful day-to-day variation (greater within-person vs between-person variability) in communication and mood.

Self-criticism and dependency predict affective variability in borderline personality disorder: An ecological momentary assessment study.

Affective variability is a defining feature of borderline personality disorder (BPD). We hypothesize that patients with BPD who score higher on self-criticism and/or dependency-patients with a relative emphasis on self-definition and interpersonal relatedness, respectively-are characterized by more affective variability in positive and negative emotions. To examine this hypothesis, a sample of 32 patients with BPD reported their momentary feelings of anger, depression, anxiety, cheerfulness, and relaxation in an experience sampling study with 10 random signals scheduled per day for 8 days. Using heterogeneous linear mixed models, results indicate that patients with BPD who score higher on self-criticism show more within-person variance (WPV) in anger, depression, anxiety, cheerfulness, and feeling relaxed, whereas patients who score higher on dependency show more WPV in anger but less WPV in anxiety and feeling relaxed. Consequently, individual differences in affective variability in BPD are, after adjustment for the confounding between the mean and WPV of affect, related to personality vulnerabilities like self-criticism and dependency. These results add evidence to two-polarities models of personality and the existing view that there is substantial heterogeneity in BPD. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Mixed-effects Location Scale Modeling For The Analysis Of Accelerometry Data

PURPOSE: To introduce a statistical technique, the mixed-effects location scale model, for analysis of longitudinal accelerometer-based physical activity (PA) data. This approach jointly models both the mean (location) and within-subject variability (scale) of participants’ PA over time as a function of covariates, since within-person variability may be an important construct to explore in PA interventions. Random effects are included in both models to allow for subject-specific deviations beyond the effect of covariates. These random effects can be correlated. METHODS: Participants (N=204, 77% female, age=33±11y, BMI=28.2±7.1 kg/m2) in the Make Better Choices Study were randomized to one of two activity-related intervention arms: 1) increase moderate-to-vigorous PA (MVPA) (PA group) or 2) decrease sedentary active control (SB group). Physical activity was measured by accelerometer for 5 weeks: a 2 week baseline assessment phase and a 3 week intervention follow-up phase: week 1 (rx1) and weeks 2 and 3 (rx23). The outcome MVPA min/d was analyzed using the mixed-effects location scale model in the MIXREGLS software program in STATA. RESULTS: The mean model shows a significant group by time interaction (MVPA group by rx1: B=6.32 (95%CI: 3.93, 8.7) MVPA group by rx23: B=9.85 (95% CI: 7.59, 12.10)) indicating that those in the PA group had significantly greater MVPA min/d at rx1 and rx23 compared to the SB group. The PA group by rx23 interaction was significant in the within-subject variance model, suggesting that those in the PA group had significantly more variability in MVPA min/d during follow-up phase rx23 compared to the SB group. The random-location effect is positively associated with the within subject variance, participants with higher mean min/d MVPA tend to have higher min/d MVPA variability (τι=0.70 (95% CI: 0.60, 0.80)). The scale standard deviation is significant indicating that some participant’s MVPA min/d are significantly more dispersed than other participants even after adjusting for group and time effects (σω=0.60 (95% CI: 0.55, 0.64)). CONCLUSIONS: The location-scale mixed model provides a new approach for examining the mean and variability of min/d of MVPA in longitudinal data. To demonstrate, we applied this model to a randomized controlled trial to increase PA in inactive adults.

Do Feelings of Defeat and Entrapment Change over Time? An Investigation of the Integrated Motivational-Volitional Model of Suicidal Behaviour Using Ecological Momentary Assessments.

(1) Background. Defeat and entrapment have been highlighted as major risk factors of suicidal ideation and behavior. Nevertheless, little is known about their short-term variability and their longitudinal association in real-time. Therefore, this study aims to investigate whether defeat and entrapment change over time and whether defeat predicts entrapment as stated by the integrated motivational–volitional model of suicidal behavior. (2) Methods. Healthy participants (n = 61) underwent a 7-day smartphone-based ecological momentary assessment (EMA) on suicidal ideation/behavior and relevant risk factors, including defeat and entrapment and a comprehensive baseline (T0) and post (T2) assessment. (3) Results. Mean squared successive differences (MSSD) and intraclass correlations (ICC) support the temporal instability as well as within-person variability of defeat and entrapment. Multilevel analyses revealed that during EMA, defeat was positively associated with entrapment at the same measurement. However, defeat could not predict entrapment to the next measurement (approximately two hours later). (4) Conclusion. This study provides evidence on the short-term variability of defeat and entrapment highlighting that repeated measurement of defeat and entrapment—preferably in real time—is necessary in order to adequately capture the actual empirical relations of these variables and not to overlook significant within-person variability. Further research—especially within clinical samples—seems warranted.

Step Out of Line: Modeling Nonlinear Effects and Dynamics in Close-Relationships Research

Despite widespread acknowledgment that close relationships frequently involve tumultuous and dynamic experiences, most models in relationship psychology focus on linear relationship processes. Modeling nonlinear patterns can, however, be an important way to assess and better understand the complexities inherent in close relationships. In this article, I draw on one of the most widely studied theories in relationship science—attachment theory—to illustrate how modeling nonlinear effects between variables (i.e., curvilinear effects) and nonlinear dynamics across time (i.e., within-person variation and within-dyad flexibility) can reconcile inconsistencies in the literature, reveal unique relationship experiences, and broaden our understanding of complex relationship processes.

Daily emotional well-being during the COVID-19 pandemic.

The COVID‐19 outbreak has become one of the largest public health crises of our time. Governments have responded by implementing self‐isolation and physical distancing measures that have profoundly impacted daily life throughout the world. In this study, we aimed to investigate how people experience the activities, interactions, and settings of their lives during the pandemic. The sample (N = 604) was assessed in Ireland on the 25 March 2020, following the closure of schools and non‐essential businesses. We examined within‐person variance in emotional well‐being and how people spend their time. We found that while most time was spent in the home (74%), time spent outdoors (8%) was associated with markedly raised positive affect and reduced negative emotions. Exercising, going for walks, gardening, pursuing hobbies, and taking care of children were the activities associated with the greatest affective benefits. Home‐schooling children and obtaining information about COVID‐19 were ranked lowest of all activities in terms of emotional experience. These findings highlight activities that may play a protective role in relation to well‐being during the pandemic, the importance of setting limits for exposure to COVID‐19‐related media coverage, and the need for greater educational supports to facilitate home‐schooling during this challenging period.