How acute affect dynamics impact longitudinal changes in physical activity among children.

Research examined how acute affect dynamics, including stability and context-dependency, contribute to changes in children's physical activity levels as they transition from late-childhood to early-adolescence. Children (N = 151) (ages 8-12 years at baseline) participated in an ecological momentary assessment and accelerometry study with six semi-annual bursts (7 days each) across three years. A two-stage mixed-effects multiple location-scale model tested random intercept, variance, and slope estimates for positive affect as predictors of moderate-to-vigorous physical activity (MVPA). Multi-year declines in MVPA were greater for children who had greater subject-level variance in positive affect. Children who experienced more positive affect when alone did not experience steeper declines in physical activity. Interventions aiming for long-term modifications in children's physical activity may focus on buffering the effects of within-day fluctuations in affect or tailoring programs to fit the needs of "acute dynamic process phenotypes."

The Effect of Momentary Affect on Substance Use among Young Adults Who Experience Homelessness.

IntroductionLittle is known about the momentary patterns and predictors of substance use among young adults who experience homelessness. To enhance understanding of substance use patterns, smartphone-based ecological momentary assessment (EMA) was utilized to examine the real-time association between affect and substance use. Methods: 251 young adults (aged 18-27) with history of homelessness were recruited from supportive housing programs and drop-in facilities in Los Angeles. Exploratory factor analysis was used to examine the latent structure of positive and negative affective states and mixed-effects logistic regression models were completed separately for both the full remaining sample (n = 227) and a subsample of alcohol or cannabis users (n = 145) to evaluate whether positive or negative affect predicted lead, recent, or lagged substance use. Results: Greater positive affect within-person was associated with greater odds of alcohol or cannabis use within the past two hours, and participants who reported feeling more negative than their peers experienced greater odds of reporting use within the past 4 h and the following two hours. Conclusion: Results suggest that individuals experience a heightened positive mood compared to their own average mood, concurrently or immediately after engaging in alcohol or cannabis use. Heightened positive mood might be an anticipatory effect of drinking or cannabis use. Future research should consider a longer study period to capture multiple drinking or drug use events over a longer period and consider more environmental exposures that may influence the frequency or intensity of substance use.

Investigating Sleep Disturbance and Its Correlates Among Formerly Homeless Adults in Permanent Supportive Housing.

BACKGROUND: Adults experiencing homelessness have a high burden of sleep disturbance, which may be reduced by accessing permanent supportive housing. OBJECTIVES: To assess sleep disturbances and their correlates, including demographics, activity level, health status, age-related health issues (eg, functionality and cognitive impairment), substance use, and homelessness history in a sample of permanent supportive housing (PSH) tenants. RESEARCH DESIGN: Cross-sectional survey design. SUBJECTS: A total of 237 formerly homeless adults between 45 and 80 years old. MEASURES: The Patient-Reported Outcomes Measurement Information System (PROMIS) Sleep Disturbance short form was used to measure sleep disturbance. RESULTS: Twenty-eight percent of our sample had PROMIS scores indicative of a moderate or severe sleep disturbance. Functional impairment, pain, and mental health comorbidities were associated with increased sleep disturbance in multivariable linear regression analyses. The number of years a person experienced homelessness was inversely associated with sleep disturbance. CONCLUSIONS: This study supports the need to screen for sleep disturbances among PSH tenants. The findings suggest that supportive services in PSH may need to include integrated physical and behavioral health care, pain management, and interventions designed to address activities of daily livings to improve tenant sleep. They also suggest that improved sleep may help reduce PSH tenant pain, impairment, and mental health symptoms among PSH tenants.

Examining HIV Risk and Exchange Sex Among Current and Formerly Homeless Young Adults.

This study investigated HIV risk among homeless and formerly homeless young adults by examining risky sex behaviors (e.g., condomless sex, exchange sex, and sex with multiple persons) using 90-day and daily recall methods. Data came from a sample of young adults (aged 18-27) with current (n = 101) or past (n = 109) homelessness experience in Los Angeles, California, recruited between 2017 and 2019. Baseline surveys queried demographics and sexual history. Daily retrospective surveys queried sexual events. Multiple logistic regressions were used to test the effects of demographic characteristics including homelessness history, relationship status, substance use, and sexual history on risky sex outcomes. In this sample, 26% reported never using a condom during anal or vaginal sex in the past 90 days, 5% reported testing positive for HIV, 82% had limited to no knowledge of preexposure prophylaxis, and 8% reported having had exchange sex during a 7-day measurement period, with those experiencing homelessness more likely to report. The study suggests supportive housing can reduce the occurrence of exchange sex but that HIV prevention services are still needed in homeless and housing programs to promote safe sexual practices.

Bi-Directional Associations Between Real-Time Affect and Physical Activity in Weight-Discordant Siblings.

Pediatric obesity confers increased risk for a host of negative psychological and physical health consequences and is reliably linked to low levels of physical activity. Affective antecedents and consequences of physical activity are thought to be important for the development and maintenance of such behavior, though research examining these associations in youth across the weight spectrum remains limited. OBJECTIVE: This study examined bi-directional associations between affect and physical activity (i.e., moderate-to-vigorous physical activity [MVPA] and total activity counts), and the extent to which weight (body mass index z-score [z-BMI]) moderated these associations. METHODS: Participants were drawn from a prior study of siblings (N = 77; mean age = 15.4 ± 1.4 years) discordant for weight status (39 nonoverweight siblings, 38 siblings with overweight/obesity) who completed ecological momentary assessment (EMA) with accelerometer-assessed physical activity. RESULTS: Generalized linear mixed models indicated z-BMI moderated trait-level and momentary associations. When adolescents with higher z-BMI reported momentary negative affect, they evidenced less MVPA within the next hour. Across the sample, greater overall activity was associated with lower negative affect. However, at the momentary level, when adolescents with higher (but not lower) z-BMI evidenced greater activity, they reported decreases in negative affect. CONCLUSIONS: Findings indicate affective experiences surrounding physical activity differ according to z-BMI. Specifically, momentary negative affect may impede momentary MVPA among youth with higher z-BMI. Further research is warranted to elucidate factors influencing these momentary associations and the extent to which these momentary associations prospectively predict weight change.

A Machine Learning Approach to Passively Informed Prediction of Mental Health Risk in People with Diabetes: Retrospective Case-Control Analysis.

BACKGROUND: Proactive detection of mental health needs among people with diabetes mellitus could facilitate early intervention, improve overall health and quality of life, and reduce individual and societal health and economic burdens. Passive sensing and ecological momentary assessment are relatively newer methods that may be leveraged for such proactive detection. OBJECTIVE: The primary aim of this study was to conceptualize, develop, and evaluate a novel machine learning approach for predicting mental health risk in people with diabetes mellitus. METHODS: A retrospective study was designed to develop and evaluate a machine learning model, utilizing data collected from 142,432 individuals with diabetes enrolled in the Livongo for Diabetes program. First, participants' mental health statuses were verified using prescription and medical and pharmacy claims data. Next, four categories of passive sensing signals were extracted from the participants' behavior in the program, including demographics and glucometer, coaching, and event data. Data sets were then assembled to create participant-period instances, and descriptive analyses were conducted to understand the correlation between mental health status and passive sensing signals. Passive sensing signals were then entered into the model to train and test its performance. The model was evaluated based on seven measures: sensitivity, specificity, precision, area under the curve, F1 score, accuracy, and confusion matrix. SHapley Additive exPlanations (SHAP) values were computed to determine the importance of individual signals. RESULTS: In the training (and validation) and three subsequent test sets, the model achieved a confidence score greater than 0.5 for sensitivity, specificity, area under the curve, and accuracy. Signals identified as important by SHAP values included demographics such as race and gender, participant's emotional state during blood glucose checks, time of day of blood glucose checks, blood glucose values, and interaction with the Livongo mobile app and web platform. CONCLUSIONS: Results of this study demonstrate the utility of a passively informed mental health risk algorithm and invite further exploration to identify additional signals and determine when and where such algorithms should be deployed.

Risk behaviour and access to HIV/AIDS prevention services among formerly homeless young adults living in housing programmes.

Young adults who experience homelessness have high rates of sexually transmitted infections (STIs) including HIV. Homelessness services programmes that provide housing to young adults have the capacity to reduce STI risk profiles. This study analysed data from 140 formerly homeless adults who moved into a housing programme in Los Angeles County between the ages of 18 and 25 years to investigate risk behaviour and access to HIV/AIDS prevention services. More than three quarters of participants reported sexual activity (vaginal or anal sex) in the prior 3 months, with 63% reporting any unprotected vaginal or anal sex, 29% reporting unprotected sex with a nonserious partner, 40% reporting multiple partners, and 11% reporting exchange sex. About three quarters reported a past-year HIV test. About half of the sample had never heard of pre-exposure prophylaxis (PrEP), 12% had heard of it but didn't know what it was, 25% reported knowing a little bit, and 15% said they knew a lot about PrEP. Slightly more than 4% of the overall sample reported being HIV positive. These findings suggest that housing programmes may be a prime location to implement HIV prevention services.

Real-Time Data Collection to Examine Relations Between Physical Activity and Affect in Adults With Mental Illness.

Adults with serious mental illness engage in limited physical activity, which contributes to significant health disparities. This study explored the use of both ecological momentary assessments (EMAs) and activity trackers in adults with serious mental illness to examine the bidirectional relationship between activity and affect with multilevel modeling. Affective states were assessed up to seven times per day using EMA across 4 days. The participants (n = 20) were equipped with a waist-worn accelerometer to measure moderate to vigorous physical activity. The participants had a mean EMA compliance rate of 88.3%, and over 90% of completed EMAs were matched with 30-min windows of accelerometer wear. The participants who reported more positive affect than others had a higher probability of engaging in moderate to vigorous physical activity. Engaging in more moderate to vigorous physical activity than one's usual was associated with more negative affect. This study begins to address the effect of momentary mood on physical activity in a population of adults that is typically difficult to reach.

MixWILD: A program for examining the effects of variance and slope of time-varying variables in intensive longitudinal data.

The use of intensive sampling methods, such as ecological momentary assessment (EMA), is increasingly prominent in medical research. However, inferences from such data are often limited to the subject-specific mean of the outcome and between-subject variance (i.e., random intercept), despite the capability to examine within-subject variance (i.e., random scale) and associations between covariates and subject-specific mean (i.e., random slope). MixWILD (Mixed model analysis With Intensive Longitudinal Data) is statistical software that tests the effects of subject-level parameters (variance and slope) of time-varying variables, specifically in the context of studies using intensive sampling methods, such as ecological momentary assessment. MixWILD combines estimation of a stage 1 mixed-effects location-scale (MELS) model, including estimation of the subject-specific random effects, with a subsequent stage 2 linear or binary/ordinal logistic regression in which values sampled from each subject's random effect distributions can be used as regressors (and then the results are aggregated across replications). Computations within MixWILD were written in FORTRAN and use maximum likelihood estimation, utilizing both the expectation-maximization (EM) algorithm and a Newton-Raphson solution. The mean and variance of each individual's random effects used in the sampling are estimated using empirical Bayes equations. This manuscript details the underlying procedures and provides examples illustrating standalone usage and features of MixWILD and its GUI. MixWILD is generalizable to a variety of data collection strategies (i.e., EMA, sensors) as a robust and reproducible method to test predictors of variability in level 1 outcomes and the associations between subject-level parameters (variances and slopes) and level 2 outcomes.

Within-Subject Effects of Stress on Weight-Related Parenting Practices in Mothers: An Ecological Momentary Assessment Study.

BACKGROUND: Stress may compromise parenting practices related to children's dietary intake, physical activity, and sedentary behavior. PURPOSE: The current study used Ecological Momentary Assessment (EMA) to examine microtemporal sequences underlying maternal stress and subsequent weight-related parenting practices. METHODS: Mothers (n = 199) of children aged 8-12 years participated in two separate 7-day waves of EMA with up to eight randomly prompted surveys per day during children's nonschool time. EMA items assessed stress and weight-related parenting practices. RESULTS: When mothers reported experiencing greater stress than usual, they subsequently engaged in less physical activity parenting (e.g., encouraging physical activity; p < .05) and more sedentary screen behavior parenting (e.g., limiting TV/video games; p < .05) over the next 2 hr. CONCLUSIONS: Addressing within-day variations in maternal stress may be an important component of parent-focused child obesity prevention interventions.

Do fluctuations in positive affective and physical feeling states predict physical activity and sedentary time?

OBJECTIVES: Higher levels of positive affect and feelings of energy and vitality are associated with greater physical activity (PA) and lower sedentary time (ST). However, whether fluctuations in these feelings contribute to the regulation of these behaviors is unclear. This study examined the extent to which within-person variability in positive affect and feeling energetic predicted participants' overall levels of PA and ST. DESIGN: This analysis combined data from four ecological momentary assessment (EMA) studies (agerange: 8-73 years) with ambulatory monitoring via waist-worn accelerometry (N=661). METHODS: Positive affect and energy were assessed through EMA several times per day across 4-7 days. Accelerometer data was used to create the following behavioral outcomes: (1) meeting MVPA guidelines (children: 60 minutes/day, adults: 30 minutes/day) and (2) minutes of ST per hour of accelerometer wear. A two-stage analytic approach was used to test the study aim. In the first stage, Mixed-Effects Location Scale Modeling decomposed mean levels and variability in positive affect and energy. In the second stage, a linear or logistic regression (depending on whether the outcome was continuous or dichotomous, respectively) was tested to investigate associations between subject-level mean and variability in EMA ratings and the behavioral outcome. RESULTS: Greater subject-level variability but not subject-level mean of feeling energetic was associated with lower odds of meeting MVPA guidelines (ß=-0.43, p<0.05). CONCLUSIONS: Fluctuations in physical feeling states may deplete self-regulatory resources involved in planning and implementing PA behavior. Alternatively, being more physically active may stabilize one's perceived energy levels.

Concordance and predictors of concordance of children's dietary intake as reported via ecological momentary assessment and 24 h recall.

OBJECTIVE: To provide preliminary evidence in support of using ecological momentary assessment (EMA), a real-time data capture method involving repeated assessments, to measure dietary intake in children by examining the concordance of children's dietary reports through EMA and 24 h recall. DESIGN: Children completed eight days of EMA surveys, reporting on recent dietary intake of four pre-specified food categories ('Fruits or Vegetables', 'Chips or Fries', 'Pastries or Sweets', 'Soda or Energy Drinks'), and completed two 24 h recalls during the same period. Concordance of children's reports of intake during matched two-hour time windows from EMA and 24 h dietary recall was assessed using cross-tabulation. Multilevel logistic regression examined potential person-level (i.e. sex, age, ethnicity and BMI category) predictors of concordance. SETTING: Children in Los Angeles County, USA, enrolled in the Mothers' and Their Children's Health (MATCH) study. SUBJECTS: One hundred and forty-four 144 children (53 % female; mean age 9·6 (sd 0·9) years; 34·0 % overweight/obese). RESULTS: Two-hour concordance varied by food category, ranging from 64·9 % for 'Fruits/Vegetables' to 89·9 % for 'Soda/Energy Drinks'. In multilevel models, overweight/obese (v. lean) was associated with greater odds (OR; 95 % CI) of concordant reporting for 'Soda/Energy Drinks' (2·01; 1·06, 4·04) and 'Pastries/Sweets' (1·61; 1·03, 2·52). Odds of concordant reporting were higher for Hispanic (v. non-Hispanic) children for 'Pastries/Sweets' (1·55; 1·02, 2·36) and for girls (v. boys) for 'Fruits/Vegetables' (1·36; 1·01, 1·83). CONCLUSIONS: Concordance differed by food category as well as by person-level characteristics. Future research should continue to explore use of EMA to facilitate dietary assessment in children.

Development of a Just-in-Time Adaptive Intervention for Smoking Cessation Among Korean American Emerging Adults.

PURPOSE: Cigarette smoking is a preventable risk factor that contributes to unnecessary lung cancer burden among Korean Americans and there is limited research on effective smoking cessation strategies for this population. Smartphone-based smoking cessation apps that leverage just-in-time adaptive interventions (JITAIs) hold promise for smokers attempting to quit. However, little is known about how to develop and tailor a smoking cessation JITAI for Korean American emerging adult (KAEA) smokers. METHOD: This paper documents the development process of MyQuit USC according to design guidelines for JITAI. Our development process builds on findings from a prior ecological momentary assessment study by using qualitative research methods. Semi-structured interviews and a focus group were conducted to inform which intervention options to offer and the decision rules that dictate their delivery. RESULTS: Qualitative findings highlighted that (1) smoking episodes are highly context-driven and that (2) KAEA smokers believe they need personalized cessation strategies tailored to different contexts. Thus, MyQuit USC operates via decision rules that guide the delivery of personalized implementation intentions, which are contingent on dynamic factors, to be delivered "just in time" at user-scheduled, high-risk smoking situations. CONCLUSION: Through an iterative design process, informed by quantitative and qualitative formative research, we developed a smoking cessation JITAI tailored specifically for KAEA smokers. Further testing is under way to optimize future versions of the app with the most effective intervention strategies and decision rules. MyQuit USC has the potential to provide cessation support in real-world settings, when KAEAs need them the most.

Feasibility and Performance Test of a Real-Time Sensor-Informed Context-Sensitive Ecological Momentary Assessment to Capture Physical Activity.

BACKGROUND: Objective physical activity monitors (eg, accelerometers) have high rates of nonwear and do not provide contextual information about behavior. OBJECTIVE: This study tested performance and value of a mobile phone app that combined objective and real-time self-report methods to measure physical activity using sensor-informed context-sensitive ecological momentary assessment (CS-EMA). METHODS: The app was programmed to prompt CS-EMA surveys immediately after 3 types of events detected by the mobile phone's built-in motion sensor: (1) Activity (ie, mobile phone movement), (2) No-Activity (ie, mobile phone nonmovement), and (3) No-Data (ie, mobile phone or app powered off). In addition, the app triggered random (ie, signal-contingent) ecological momentary assessment (R-EMA) prompts (up to 7 per day). A sample of 39 ethnically diverse high school students in the United States (aged 14-18, 54% female) tested the app over 14 continuous days during nonschool time. Both CS-EMA and R-EMA prompts assessed activity type (eg, reading or doing homework, eating or drinking, sports or exercising) and contextual characteristics of the activity (eg, location, social company, purpose). Activity was also measured with a waist-worn Actigraph accelerometer. RESULTS: The average CS-EMA + R-EMA prompt compliance and survey completion rates were 80.5% and 98.5%, respectively. More moderate-to-vigorous intensity physical activity was recorded by the waist-worn accelerometer in the 30 minutes before CS-EMA activity prompts (M=5.84 minutes) than CS-EMA No-Activity (M=1.11 minutes) and CS-EMA No-Data (M=0.76 minute) prompts (P's<.001). Participants were almost 5 times as likely to report going somewhere (ie, active or motorized transit) in the 30 minutes before CS-EMA Activity than R-EMA prompts (odds ratio=4.91, 95% confidence interval=2.16-11.12). CONCLUSIONS: Mobile phone apps using motion sensor-informed CS-EMA are acceptable among high school students and may be used to augment objective physical activity data collected from traditional waist-worn accelerometers.

Using Ecological Momentary Assessment to Identify Common Smoking Situations Among Korean American Emerging Adults.

The present study provides detailed contextual information about smoking habits among young Korean American smokers with the goal of characterizing situations where they are most at risk for smoking. Relevant situational factors included location, social context, concurrent activities, time of day, affective states, and food and beverage consumption. Using ecological momentary assessment (EMA) over 7 days, participants (N = 78) were instructed to respond to smoking prompts (n = 2614) and non-smoking prompts (n = 2136) randomly scheduled throughout the day. At each prompt, participants completed a short survey about immediate contextual factors. We used multilevel models to evaluate the association between contextual factors and smoking and further explored the distribution of smoking locations and concurrent activities across each social context and reason for smoking. Compared to non-smoking events, smoking events were associated with being outside, the presence of Korean friends, socializing, consuming alcohol, and experiencing more stress relative to one's average stress level (all ps < .01). Further analyses involving only smoking events showed that when participants smoked alone, they were most commonly at home (50 %) and most often studying/working (28 %). When smoking with Korean friends, participants were most often outside (38 %) and socializing (54 %). When smoking to reduce craving, participants were most often at home (39 %) and studying/working (25 %). To our knowledge, this is the first study to provide detailed descriptions of real-time smoking contexts among young Korean American smokers. Information with this level of granularity is needed to develop effective just-in-time adaptive interventions (JITAIs) for smoking cessation.

Within-Day Time-Varying Associations Between Behavioral Cognitions and Physical Activity in Adults.

This study used time-varying effect modeling to examine time-of-day differences in how behavioral cognitions predict subsequent physical activity (PA). Adults (N = 116) participated in three 4-day "bursts" of ecological momentary assessment (EMA). Participants were prompted with eight EMA questionnaires per day assessing behavioral cognitions (i.e., intentions, self-efficacy, outcome expectations) and wore an accelerometer during waking hours. Subsequent PA was operationalized as accelerometer-derived minutes of moderate- or vigorousintensity PA in the 2 hr following the EMA prompt. On weekdays, intentions positively predicted subsequent PA in the morning (9:25 a.m.-11:45 a.m.) and in the evening (8:15 p.m.-10:00 p.m.). Self-efficacy positively predicted subsequent PA on weekday evenings (7:35 p.m.-10:00 p.m.). Outcome expectations were unrelated to subsequent PA on weekdays. On weekend days, behavior cognitions and subsequent PA were unrelated regardless of time of day. This study identifies windows of opportunity and vulnerability for motivation-based PA interventions aiming to deliver intervention content within the context of adults' daily lives.

The Effect of a Digital Mental Health Program on Anxiety and Depression Symptoms: Retrospective Analysis of Clinical Severity.

BACKGROUND: Evidence-based digital health programs have shown efficacy in being primary tools to improve emotional and mental health, as well as offering supplementary support to individuals undergoing psychotherapy for anxiety, depression, and other mental health disorders. However, information is lacking about the dose response to digital mental health interventions. OBJECTIVE: The objective of the study was to examine the effect of time in program and program usage on symptom change among individuals enrolled in a real-world comprehensive digital mental health program (myStrength) who are experiencing severe anxiety or depression. METHODS: Eligible participants (N=18,626) were adults aged 18 years and older who were enrolled in myStrength for at least four weeks as part of their employee wellness benefit program, who completed baseline, the 2-week, 2-month, and 6-month surveys querying symptoms of anxiety (Generalized Anxiety Disorder-7 [GAD-7]) and depression (Patient Health Questionnaire-9 [PHQ-9]). Linear growth curve models were used to analyze the effect of average weekly program usage on subsequent GAD-7 and PHQ-9 scores for participants with scores indicating severe anxiety (GAD-7≥15) or depression (PHQ-9≥15). All models were adjusted for baseline score and demographics. RESULTS: Participants in the study (N=1519) were 77.4% female (1176/1519), had a mean age of 45 years (SD 14 years), and had an average enrollment time of 3 months. At baseline, participants reported an average of 9.39 (SD 6.04) on the GAD-7 and 11.0 (SD 6.6) on the PHQ-9. Those who reported 6-month results had an average of 8.18 (SD 6.15) on the GAD-7 and 9.18 (SD 6.79) on the PHQ-9. Participants with severe scores (n=506) experienced a significant improvement of 2.97 (SE 0.35) and 3.97 (SE 0.46) at each time point for anxiety and depression, respectively (t=-8.53 and t=-8.69, respectively; Ps<.001). Those with severe baseline scores also saw a reduction of 0.27 (SE 0.08) and 0.25 (SE 0.09) points in anxiety and depression, respectively, for each additional program activity per week (t=-3.47 and t=-2.66, respectively; Ps<.05). CONCLUSIONS: For participants with severe baseline scores, the study found a clinically significant reduction of approximately 9 points for anxiety and 12 points for depression after 6 months of enrollment, suggesting that interventions targeting mental health must maintain active, ongoing engagement when symptoms are present and be available as a continuous resource to maximize clinical impact, specifically in those experiencing severe anxiety or depression. Moreover, a dosing effect was shown, indicating improvement in outcomes among participants who engaged with the program every other day for both anxiety and depression. This suggests that digital mental health programs that provide both interesting and evidence-based activities could be more successful in further improving mental health outcomes.

Dyadic Effects of Pokémon GO on Physical Activity and Sedentary Behavior in Mothers and Children.

Family-based mobile health applications may be an opportunity to increase children's physical activity (PA) levels. Researchers have highlighted Pokémon GO as a potential model for future PA interventions as it integrates PA with social gamification. This study provides descriptive data on Pokémon GO usage among mothers and their children and examines differences in moderate to vigorous PA (MVPA) over time among individuals playing Pokémon GO compared to non-players using a dyadic subsample from a three-year longitudinal study. After the release of Pokémon Go in July 2016, 156 mother-child dyads completed questionnaires about Pokémon Go usage and wore accelerometers continuously for seven days at baseline (Sep 2016), six months, and twelve months. Independent sample t-tests and chi-square tests were used to investigate differences in demographics and daily MVPA by player status cross-sectionally at each time point. At baseline, six mothers and 21 children reported playing Pokémon Go. Baseline demographic characteristics were not associated with player status. Across time, mothers engaged in an average of 21.12 minutes of daily MVPA (SD = 19.7) and children in 29.35 minutes (SD = 18.88). Children's daily MVPA did not differ by player status, but mothers who reported playing engaged in higher daily MVPA (M = 46.84, SD = 38.07) compared to non-players (M = 21.40, SD = 23.31). This naturalistic study lacked power to further analyze changes in MVPA after the release of the game due to lack of engagement with Pokémon GO. Understanding how to design a family-oriented game to bring together gamification, physical activity, and family-based interventions will be important for future public health efforts.

Food insecurity, hunger, stress, and homelessness among young adults.

BACKGROUND: Compared to the effects of stress on hunger, the temporal effect of hunger on stress levels is less understood, especially in the context of everyday lives of vulnerable populations with unstable access to food. OBJECTIVE: Our objective was to examine the effects of food insecurity and momentary hunger on momentary stress and stress variability in a sample of currently and formerly homeless young adults. METHOD: We used a 7-day ecological momentary assessment study querying affect, hunger, and risky behaviors. A mixed-effects location scale model was used to examine the effects of hunger on mean levels and within- and between-subjects variability of stress with 100 currently homeless and 69 formerly homeless young adults ages 18-29 in Los Angeles County, California. RESULTS: When individuals experienced greater-than-average hunger, they then experienced greater stress variability at the next prompt, showing the impact of hunger on stress at the momentary level. Those with higher average levels of stress, regardless of hunger, became substantially more stressed when becoming hungry compared to their generally less stressed counterparts. CONCLUSIONS: The study shows the extent to which food insecurity results in erratic stress among vulnerable populations and how high levels of hunger may lead to a more inconsistent stress response. Findings reinforce the need for more mental health services and food programs for young adults who have experienced homelessness. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Feasibility and Acceptability of Ecological Momentary Assessment With Young Adults Who Are Currently or Were Formerly Homeless: Mixed Methods Study.

BACKGROUND: Ecological momentary assessment (EMA) has been used with young people experiencing homelessness to gather information on contexts associated with homelessness and risk behavior in real time and has proven feasible in this population. However, the extent to which EMA may affect the attitudes or behaviors of young adults who are currently or were formerly homeless and are residing in supportive housing has not been well investigated. OBJECTIVE: This study aims to describe the feedback regarding EMA study participation from young adults who are currently or were formerly homeless and examine the reactivity to EMA participation and compliance. METHODS: This mixed methods study used cross-sectional data collected before and after EMA, intensive longitudinal data from a 7-day EMA prompting period, and focus groups of young adults who are currently or were formerly homeless in Los Angeles, California, between 2017 and 2019. RESULTS: Qualitative data confirmed the quantitative findings. Differences in the experience of EMA between young adults who are currently or were formerly homeless were found to be related to stress or anxiety, interference with daily life, difficulty charging, behavior change, and honesty in responses. Anxiety and depression symptomatology decreased from before to after EMA; however, compliance was not significantly associated with this decrease. CONCLUSIONS: The results point to special considerations when administering EMA to young adults who are currently or were formerly homeless. EMA appears to be slightly more burdensome for young adults who are currently homeless than for those residing in supportive housing, which are nuances to consider in the study design. The lack of a relationship between study compliance and symptomatology suggests low levels of reactivity.