Ecological Momentary Assessment Data Research Articles

Feasibility of a Mobile Phone App to Support Recovery From Addiction in China: Secondary Analysis of a Pilot Study.

BackgroundMobile health technologies have been found to improve the self-management of chronic diseases. However, there is limited research regarding their feasibility in supporting recovery from substance use disorders (SUDs) in China.ObjectiveThe objective of this study was to examine the feasibility of a mobile phone-based ecological momentary assessment (EMA) app by testing the concordance of drug use assessed by the EMA, urine testing, and a life experience timeline (LET) assessment.MethodsA total of 75 participants dependent on heroin or amphetamine-type stimulant (ATS) in Shanghai were recruited to participate in a 4-week pilot study. Of the participants, 50 (67% [50/75]) were randomly assigned to the experimental group and 25 (33% [25/75]) were assigned to the control group. The experimental group used mobile health (mHealth) based EMA technology to assess their daily drug use in natural environments and received 2 short health messages each day, whereas the control group only received 2 short health messages each day from the app. Urine tests and LET assessments were conducted each week and a post-intervention survey was administered to both groups. The correlations among the EMA, the LET assessment, and the urine test were investigated.ResultsThe mean age of the participants was 41.6 (SD 8.0) years, and 71% (53/75) were male. During the 4 weeks of observation, 690 daily EMA survey data were recorded, with a response rate of 49.29% (690/1400). With respect to drug use, the percent of agreement between the EMA and the LET was 66.7%, 79.2%, 72.4%, and 85.8%, respectively, for each of the 4 weeks, whereas the percent of agreement between the EMA and the urine test was 51.2%, 65.1%, 61.9%, and 71.5%, respectively. The post-intervention survey indicated that 46% (32/70) of the participants preferred face-to-face interviews rather than the mHealth app.ConclusionsThis study demonstrated poor agreement between the EMA data and the LET and found that the acceptance of mHealth among individuals with SUDs in China was not positive. Hence, greater efforts are needed to improve the feasibility of mHealth in China.

A 3-level Bayesian mixed effects location scale model with an application to ecological momentary assessment data.

Ecological momentary assessment studies usually produce intensively measured longitudinal data with large numbers of observations per unit, and research interest is often centered around understanding the changes in variation of people's thoughts, emotions and behaviors. Hedeker et al developed a 2-level mixed effects location scale model that allows observed covariates as well as unobserved variables to influence both the mean and the within-subjects variance, for a 2-level data structure where observations are nested within subjects. In some ecological momentary assessment studies, subjects are measured at multiple waves, and within each wave, subjects are measured over time. Li and Hedeker extended the original 2-level model to a 3-level data structure where observations are nested within days and days are then nested within subjects, by including a random location and scale intercept at the intermediate wave level. However, the 3-level random intercept model assumes constant response change rate for both the mean and variance. To account for changes in variance across waves, as well as clustering attributable to waves, we propose a more comprehensive location scale model that allows subject heterogeneity at baseline as well as across different waves, for a 3-level data structure where observations are nested within waves and waves are then further nested within subjects. The model parameters are estimated using Markov chain Monte Carlo methods. We provide details on the Bayesian estimation approach and demonstrate how the Stan statistical software can be used to sample from the desired distributions and achieve consistent estimates. The proposed model is validated via a series of simulation studies. Data from an adolescent smoking study are analyzed to demonstrate this approach. The analyses clearly favor the proposed model and show significant subject heterogeneity at baseline as well as change over time, for both mood mean and variance. The proposed 3-level location scale model can be widely applied to areas of research where the interest lies in the consistency in addition to the mean level of the responses.

Mobile Phone Ownership Is Not a Serious Barrier to Participation in Studies: Descriptive Study.

BackgroundRather than providing participants with study-specific data collection devices, their personal mobile phones are increasingly being used as a means for collecting geolocation and ecological momentary assessment (EMA) data in public health research.ObjectiveThe purpose of this study was to (1) describe the sociodemographic characteristics of respondents to an online survey screener assessing eligibility to participate in a mixed methods study collecting geolocation and EMA data via the participants’ personal mobile phones, and (2) examine how eligibility criteria requiring mobile phone ownership and an unlimited text messaging plan affected participant inclusion.MethodsAdult (≥18 years) daily smokers were recruited via public advertisements, free weekly newspapers, printed flyers, and word of mouth. An online survey screener was used as the initial method of determining eligibility for study participation. The survey screened for twenty-eight inclusion criteria grouped into three categories, which included (1) cell phone use, (2) tobacco use, and (3) additional criteriaResultsA total of 1003 individuals completed the online screener. Respondents were predominantly African American (605/1003, 60.3%) (60.4%), male (514/1003, 51.3%), and had a median age of 35 years (IQR 26-50). Nearly 50% (496/1003, 49.5%) were unemployed. Most smoked menthol cigarettes (699/1003, 69.7%), and had a median smoking history of 11 years (IQR 5-21). The majority owned a mobile phone (739/1003, 73.7%), could install apps (86.8%), used their mobile phone daily (89.5%), and had an unlimited text messaging plan (871/1003, 86.8%). Of those who completed the online screener, 302 were eligible to participate in the study; 163 were eligible after rescreening, and 117 were enrolled in the study. Compared to employed individuals, a significantly greater proportion of those who were unemployed were ineligible for the study based on mobile phone inclusion criteria (P<.001); yet, 46.4% (333/717) of the individuals who were unemployed met all mobile phone inclusion criteria.ConclusionsInclusion criteria requiring participants to use their personal mobile phones for data collection was not a major barrier to study participation for most respondents who completed the online screener, including those who were unemployed.Trial RegistrationClinicalTrials.gov NCT02261363; https://clinicaltrials.gov/ct2/show/NCT02261363 (Archived by WebCite at http://www.webcitation.org/6wOmDluSt)

Addressing people and place microenvironments in weight loss disparities (APP-Me): Design of a randomized controlled trial testing timely messages for weight loss behavior in low income Black and White Women

BackgroundBehavioral interventions for weight loss have been less effective in lower income and black women. These poorer outcomes may in part be related to these women having more frequent exposures to social and physical situations that are obesogenic, i.e., eating and sedentary cues or situations. ObjectivesWorking with obese, lower income Black and White Women, Addressing People and Place Microenvironments (APP-Me) was designed to create awareness of self-behavior at times and places of frequent eating and sedentary behavior. DesignAPP-Me is being evaluated in a randomized controlled trial with 240 participants recruited from federally qualified health centers located in a single Midwestern city. All participants complete four weeks of ecological momentary assessments (EMA) of situations and behavior. At the end of the four weeks, participants are randomized to enhanced usual care (UC) or UC plus APP-Me. MethodsAPP-Me is an automated short messaging system (SMS). Messages are text, image, audio, or a combination, and are delivered to participants' mobile devices with the intent of creating awareness at the times and places of frequent eating or sedentary behavior. The EMA data inform the timing of message deliveries. SummaryThis project aims to create and test timely awareness messages in a subpopulation that has not responded well to traditional behavioral interventions for weight loss. Novel aspects of the study include the involvement of a low income population, the use of data on time and place of obesogenic behavior, and message delivery time tailored to an individual's behavioral patterns.

Characterizing anger-related affect in individuals with posttraumatic stress disorder using ecological momentary assessment

This study employed secondary analyses of existing ecological momentary assessment (EMA) data to characterize hostile and irritable affect in the day-to-day experience of 52 smokers with, and 65 smokers without, posttraumatic stress disorder (PTSD). EMA monitoring occurred over a mean of 8.2 days, and participants responded to an average of 2.8 random prompts/day. Analyses included Wilcoxon rank sum tests of group differences, and path analyses of cross-lagged multilevel models. Participants with PTSD endorsed a significantly higher proportion of total EMA entries indicating hostile affect and irritable affect than did individuals without PTSD. Cross-lagged analyses indicated that over a period of hours, PTSD symptoms significantly predicted subsequent hostile and irritable affect, but hostile and irritable affect did not predict subsequent PTSD symptoms. Findings suggest that day-to-day exposure to PTSD-related trauma cues may contribute to chronically elevated levels of anger-related affect. Such heightened affective arousal may, in turn, underlie an increased risk for verbal or physical aggression, as well as other health and quality-of-life related impairments associated with PTSD. Clinical implications include conceptualizing anger treatment in the broader context of trauma history and symptoms, and specifically targeting physiological arousal and maladaptive hostile cognitions triggered by trauma reminders in patients with PTSD.

Objectively Measured Social Integration Is Associated With an Immune Risk Phenotype Following Marital Separation

Close relationships play an integral role in human development, and robust evidence links marital separation and divorce to poor health outcomes. Social integration may play a key role in this association. In many ways, the study of marital separation and divorce provides an ideal model system for a more complete understanding of the association between life stress and physical health. The current study investigated associations among objectively measured social integration, psychological distress, and biomarkers of immune health in recently separated adults (N = 49). We collected four measures of immune functioning-interleukin-6, C-reactive protein, and antibody titers to latent cytomegalovirus and Epstein-Barr virus-that were combined to yield a viral-Immune Risk Profile. To assess how variability in social integration is associated with immunological correlates following the end of a marriage, we incorporated observational ecological momentary assessment data using a novel methodology (the Electronically Activated Recorder). We found that objectively measured social behaviors are associated with concurrent viral-Immune Risk Profile scores over and above the effects of psychological distress and that psychological distress may be linked to biomarkers of immune health through social integration. This research expands current knowledge of biomarkers of immune health after divorce and separation and includes a new methodology for objective measures of social engagement.

Momentary factors during marijuana use as predictors of lapse during attempted abstinence in young adults

IntroductionYoung adults using marijuana heavily often try multiple times to quit on their own. We sought to identify momentary experiences during marijuana use that could aid in predicting lapse when young adults subsequently attempt abstinence. MethodsYoung adults (N=34) age 18–25 using marijuana ≥5days/week and planning to quit completed a survey of sociodemographic characteristics, substance use, marijuana expectancies, use motives, perceived social support, and confidence to abstain. They completed ecological momentary assessment (EMA) smartphone reports several times/day for two weeks prior to, then during two weeks of attempted abstinence. Use period EMA reports assessed affect, craving, accessibility, situational permissibility, use, and motivation to abstain. Baseline survey and EMA data were examined in relation to subsequent lapse during attempted abstinence. ResultsNearly 3 in 4 participants (73.5%) reported lapsing during attempted abstinence from marijuana. On bivariate analyses, lower baseline dependence severity score, negative effect expectancies, perceived family support, and confidence to abstain were each associated with lapse. Of the use period EMA variables, greater percent of days with marijuana use, reports of easy accessibility, and reports of situational permissibility were each associated with lapse. Modeled together, negative effect expectancies, perceived family support, confidence to abstain, and situational permissibility during use were highly accurate in predicting lapse during attempted abstinence. ConclusionsMomentary factors may add to conventionally-surveyed characteristics to enhance prediction of lapse during attempted abstinence among young adults with heavy marijuana use.Momentary assessment prior to a quit attempt may thus enable more effective personalized approaches to preventing lapse.

Social and situational characteristics associated with adolescents' drinking at party and non-party events

We investigated social and situational characteristics associated with adolescents' drinking at party and non-party events and whether these associations vary by party location (homes versus other locations). Ecological momentary assessment data were obtained over two weekends from 149 adolescents in California (46% female, M age=16.4years), using smartphone surveys administered early and late in the evening and the following morning. We assessed whether, where, and with whom adolescents drank alcohol. Social contexts with more people (RRR=1.05, p≤0.005) and with mixed gender composition (RRR=3.15, p≤0.05) were positively associated with increased risks of alcohol use at parties, but not at non-party events. Conversely, social contexts with friends were positively associated with alcohol use at non-party events (RRR=4.32, p≤0.005), but not at parties. Perceived access to alcohol was associated with increased risks for alcohol use at both party and non-party events, but the association was stronger for alcohol use at parties than non-parties (RRR=1.85, p<0.005 versus 4.01, p≤0.005). Additional analyses showed that contexts with mixed gender composition were positively associated with alcohol use at parties not in homes (RRR=11.29, p≤0.05), and perceptions of getting caught by parents or police were negatively associated with non-party alcohol use in homes (RRR=0.57, p≤0.005). This study identified social-ecological contexts of underage drinking parties, which are high risk settings for heavier drinking and other alcohol-related problems. Findings can inform context-based interventions to target these high-risk settings, whether at homes or other locations.

The effect of N-acetylcysteine and working memory training on cocaine use, craving and inhibition in regular cocaine users: correspondence of lab assessments and Ecological Momentary Assessment

IntroductionEffective treatment for cocaine use disorder should dampen hypersensitive cue-induced motivational processes and/or strengthen executive control. Using a randomized, double-blind, placebo-controlled intervention, the primary aim of this study was to investigate the effect of N-Acetylcysteine (NAC) and working memory (WM)-training to reduce cocaine use and craving and to improve inhibition assessed in the laboratory and during Ecological Momentary Assessment (EMA). The second aim was to examine correspondence between laboratory and EMA data. MethodsTwenty-four of 38 cocaine-using men completed a 25-day intervention with 2400mg/day NAC or placebo and WM-training as well as two lab-visits assessing cocaine use, craving and inhibition (Stop Signal task). Additionally, cocaine use, craving and cognition (Stroop task) were assessed using EMA during treatment, with 26 participants completing 819 assessments. ResultsCocaine problems according to the Drug Use Disorder Identification Test (DUDIT) decreased more after NAC than after placebo, and the proportion of cocaine-positive urines at lab-visit 2 was lower in the NAC group. No NAC effects were found on craving. For cocaine use and craving, results from the lab data were generally similar to EMA results. NAC also showed some effects on cognitive control: improved inhibition assessed with the Stop Signal task in the lab, and decreased classic Stroop performance during EMA. There were no significant effects of number of completed WM-training sessions. ConclusionsOverall this study revealed mixed findings regarding the treatment of cocaine use disorders with NAC and WM-training. The effect of NAC on inhibition should be further investigated.

The Association of Cigarette Smoking With High-Frequency Heart Rate Variability: An Ecological Momentary Assessment Study.

Evidence from both laboratory and observational studies suggests that acute and chronic smoking leads to reduced high-frequency heart rate variability (HF-HRV), a measure of cardiac vagal regulation. We used ecological momentary assessment (EMA) to study the effect of smoking on concurrent HF-HRV in a trial measuring the effects of hostility reduction and compared 24-hour HF-HRV in smokers and nonsmokers. Ambulatory electrocardiogram data were collected before randomization from 149 healthy individuals with high hostility levels (20-45 years, body mass index ≤ 32 kg/m) and paired with concurrent EMA ratings of smoking and physical position during waking hours. A multilevel mixed model was estimated associating ln(HF-HRV) from smoking status (between-person factor) and person-centered momentary smoking (within-person factor, treated as a random effect), adjusting for momentary physical position, medication use, and consumption of alcohol and caffeine. Thirty-five smokers and 114 nonsmokers provided both EMA and HF-HRV data. Within smokers, ln HF-HRV was reduced by 0.31 millisecond (p = .04) when participants reported having recently smoked cigarettes, compared with when they had not. The 24-hour HF-HRV was significantly lower in smokers (M [SD] = 5.24 [0.14] milliseconds) than nonsmokers (5.63 ± 0.07 milliseconds, p = .01). In healthy smokers with high hostility levels used as their own controls during daily living, smoking acutely reduced HF-HRV. HF-HRV was also reduced in smokers as compared with nonsmokers. Although limited by a small sample of individuals with high hostility levels, these findings nonetheless provide additional evidence that cardiac vagal regulation is lowered by cigarette smoking, which may be one of the numerous pathophysiological effects of smoking.

Feasibility of Using Ecological Momentary Assessment to Study Unaided Smoking Cessation in Couples.

Ecological momentary assessment (EMA) is a valuable method for studying smoking cessation, but feasibility has not been examined in committed couples. The current study examines the feasibility of conducting an EMA study of unaided smoking cessation in single-smoker couples. Participants were 62 single-smoker couples recruited to participate in a 21-day study of unaided smoking cessation. Quitters and Partners were given instructions to complete one morning report, three signaled reports, and one evening report per day, as well as lapse reports when necessary. They also completed a series of questionnaires at baseline and follow-up. This article examines predictors of compliance with the reporting instructions. Compliance with scheduled reporting was reasonable (Quitters: 76%, Partners: 79%). Compliance with "on-time" lapse reporting (vs. make-up reporting) was poor (Quitters: 62%, Partners: 43%). Quitters' compliance with lapse reporting was strongly associated with an orientation toward quitting. Partners' compliance with lapse reporting was associated with relationship motivation. Quitter compliance plummeted when Partners were noncompliant. Self-regulation and emotional instability were not associated with compliance but were associated with time to complete reports. Quitters' and Partners' experiences completing the study provide some insight into the dynamics of completing an EMA study as part of a dyad. Overall, this study suggests it is feasible and effective to collect EMA data on smoking cessation from couples. However, compliance with lapse reporting was poor, especially for Partners. Researchers could provide remuneration on a different schedule, provide shorter lapse reports, or omit Partner lapse reports altogether. This article examined compliance with scheduled and lapse reporting in single-smoker couples during an unaided quit attempt. Compliance with scheduled reporting was acceptable, but compliance with lapse reporting was poor, especially for Partners. Quitters' compliance with lapse reporting was heavily influenced by an orientation toward quitting, suggesting that improved screening for motivation to quit might improve compliance rates. Quitter compliance also plummeted when Partners were noncompliant. Partner demographics and relationship motivation were the best predictors of compliance. To enhance compliance, researchers might provide remuneration on a different scale, dramatically shorten lapse reports, or even omit Partner lapse reports.

Smartphone-based ecological momentary assessment (EMA) of alcohol and cannabis use in older adults with and without HIV infection

IntroductionEcological momentary assessment (EMA) has been used to characterize substance use among adult populations; however, little is known about the validity of EMA and the patterns and predictors of substance use among older adults with and without HIV infection. MethodsThirty-five (22 HIV-positive, 13 HIV-negative) older adults aged 50–74 were assessed for 14days and completed up to four smartphone-based surveys per day. ResultsParticipants completed an average of 89.5% of possible EMA surveys. EMA self-reported alcohol and cannabis use were significantly positively correlated with laboratory-assessed, self-reported days of alcohol (r=0.52, p=0.002) and cannabis (r=0.61, p<0.001) used and quantity of alcohol (r=0.42, p=0.013) and cannabis (r=0.41, p=0.016) used in the 30days prior to baseline assessment. In a subset of 15 alcohol or cannabis users, preliminary analyses of the effects of mood and pain on alcohol or cannabis use showed: 1) greater anxious mood predicted substance use at the next EMA survey (OR=1.737, p=0.023), 2) greater happiness predicted substance use later in the day (OR=1.383, p<0.001), and 3) higher pain level predicted substance use earlier in the day (OR=0.901, p=0.005). ConclusionsFindings demonstrate that EMA-measured alcohol and cannabis use has convergent validity among older adults with and without HIV infection. Preliminary results showing predictors of substance use highlight the importance of gathering EMA data to examine daily variability and time-dependent antecedents of substance use among this population.

Predicting short term mood developments among depressed patients using adherence and ecological momentary assessment data

Technology driven interventions provide us with an increasing amount of fine-grained data about the patient. This data includes regular ecological momentary assessments (EMA) but also response times to EMA questions by a user. When observing this data, we see a huge variation between the patterns exhibited by different patients. Some are more stable while others vary a lot over time. This poses a challenging problem for the domain of artificial intelligence and makes on wondering whether it is possible to predict the future mental state of a patient using the data that is available. In the end, these predictions could potentially contribute to interventions that tailor the feedback to the user on a daily basis, for example by warning a user that a fall-back might be expected during the next days, or by applying a strategy to prevent the fall-back from occurring in the first place.In this work, we focus on short term mood prediction by considering the adherence and usage data as an additional predictor. We apply recurrent neural networks to handle the temporal aspects best and try to explore whether individual, group level, or one single predictive model provides the highest predictive performance (measured using the root mean squared error (RMSE)). We use data collected from patients from five countries who used the ICT4Depression/MoodBuster platform in the context of the EU E-COMPARED project. In total, we used the data from 143 patients (with between 9 and 425days of EMA data) who were diagnosed with a major depressive disorder according to DSM-IV.Results show that we can make predictions of short term mood change quite accurate (ranging between 0.065 and 0.11). The past EMA mood ratings proved to be the most influential while adherence and usage data did not improve prediction accuracy. In general, group level predictions proved to be the most promising, however differences were not significant.Short term mood prediction remains a difficult task, but from this research we can conclude that sophisticated machine learning algorithms/setups can result in accurate performance. For future work, we want to use more data from the mobile phone to improve predictive performance of short term mood.

Using Elastic Net Penalized Cox Proportional Hazards Regression to Identify Predictors of Imminent Smoking Lapse.

Machine learning algorithms such as elastic net regression and backward selection provide a unique and powerful approach to model building given a set of psychosocial predictors of smoking lapse measured repeatedly via ecological momentary assessment (EMA). Understanding these predictors may aid in developing interventions for smoking lapse prevention. In a randomized-controlled smoking cessation trial, smartphone-based EMAs were collected from 92 participants following a scheduled quit date. This secondary analysis utilized elastic net-penalized cox proportional hazards regression and model approximation via backward elimination to (1) optimize a predictive model of time to first lapse and (2) simplify that model to its core constituent predictors to maximize parsimony and generalizability. Elastic net proportional hazards regression selected 17 of 26 possible predictors from 2065 EMAs to model time to first lapse. The predictors with the highest magnitude regression coefficients were having consumed alcohol in the past hour, being around and interacting with a smoker, and having cigarettes easily available. This model was reduced using backward elimination, retaining five predictors and approximating to 93.9% of model fit. The retained predictors included those mentioned above as well as feeling irritable and being in areas where smoking is either discouraged or allowed (as opposed to not permitted). The strongest predictors of smoking lapse were environmental in nature (e.g., being in smoking-permitted areas) as opposed to internal factors such as psychological affect. Interventions may be improved by a renewed focus of interventions on these predictors. The present study demonstrated the utility of machine learning algorithms to optimize the prediction of time to smoking lapse using EMA data. The two models generated by the present analysis found that environmental factors were most strongly related to smoking lapse. The results support the use of machine learning algorithms to investigate intensive longitudinal data, and provide a foundation for the development of highly tailored, just-in-time interventions that can target on multiple antecedents of smoking lapse.

Hierarchical Linear Modeling for Analysis of Ecological Momentary Assessment Data in Physical Medicine and Rehabilitation Research.

Ecological momentary assessment (EMA) methods collect real-time data in real-world environments, which allow physical medicine and rehabilitation researchers to examine objective outcome data and reduces bias from retrospective recall. The statistical analysis of EMA data is directly related to the research question and the temporal design of the study. Hierarchical linear modeling, which accounts for multiple observations from the same participant, is a particularly useful approach to analyzing EMA data. The objective of this paper was to introduce the process of conducting hierarchical linear modeling analyses with EMA data. This is accomplished using exemplars from recent physical medicine and rehabilitation literature.

Adolescents, alcohol, and marijuana: Context characteristics and problems associated with simultaneous use

We investigated contexts of simultaneous use of alcohol and marijuana and the impact of simultaneous use on problems among adolescents. Ecological momentary assessment data were obtained over two weekends from 150 adolescents in California (47% female, M age=16.36years), using smartphone surveys administered early and late in the evening and again the following morning. We assessed whether, in what context, and with whom adolescents drank alcohol and used other substances over 3 evening hours. We assessed problems they experienced each evening on the following morning. Results showed that greater adult supervision in every context was associated with a 55% lower risk of simultaneous use (RRR=0.45, p≤.05). Contexts with no other underage drinkers were associated with 99% lower risk of simultaneous use (RRR=0.01, p≤.005). Each occasion of simultaneous use was related to 110% increase in the number of problems (IRR=2.10, p≤.005), with 83%, 221% and 311% greater odds of violence (OR=1.83, p≤.05), driving under the influence or riding with a drunk driver (OR=3.21, p≤.05), or being drunk (OR=4.11, p≤.005). Additional analyses showed that these problems may be attributed largely to the alcohol consumed in each context. Results demonstrate that it is essential to consider situational and social characteristics of substance use contexts to better understand adolescent simultaneous use of alcohol and drugs and problems.

Regression tree analysis of ecological momentary assessment data

ABSTRACTAn increasingly popular form of data collection in health psychology research is Ecological Momentary Assessment (EMA); that is, using diaries or smartphones to collect intensive longitudinal data. This method is increasingly applied to the study of relationships between state-based aspects of individuals’ functioning and health outcomes (e.g., binge eating, alcohol use). Analysis of such data is challenging and regression tree modelling (RTM) may be a useful alternative to multilevel modelling for investigating the association between a set of explanatory variables and a continuous outcome. Furthermore, RTM outputs ‘decision trees’ that could be used by health practitioners to guide assessment and tailor intervention. In contrast to regression, RTM is able to easily accommodate many complex, higher-order interactions between predictor variables (without the need to create explicit interaction terms). These benefits make the technique useful for those interested in monitoring and intervening upon health and psychological outcomes (e.g., mood, eating behaviour, risky alcohol use, and treatment adherence). Using real data, this paper demonstrates both the benefits and limitations of RTM and how to extend these models to accommodate analysis of nested data; that is, data that arise from EMA where repeated observations are nested within individuals.

Trajectories of higher- and lower-order dimensions of negative and positive affect relative to restrictive eating in anorexia nervosa.

Despite robust support for the role of affect in the maintenance of binge eating and purging, the relationship between affect and restrictive eating remains poorly understood. To investigate the relationship between restrictive eating and affect, ecological momentary assessment data from 118 women with anorexia nervosa (AN) were used to examine trajectories of higher-order dimensions of negative affect (NA) and positive affect (PA), as well as lower-order dimensions of NA (Fear, Guilt) and PA (Joviality, Self-Assurance) relative to restrictive eating. Affect trajectories were modeled before and after restrictive eating episodes and AN subtype was examined as a moderator of these trajectories. Across the sample, Guilt significantly increased before and decreased after restrictive eating episodes. Global NA, Global PA, Fear, Joviality, and Self-Assurance did not vary relative to restrictive eating episodes across the sample. However, significant subtype by trajectory interactions were detected for PA indices. Among individuals with AN restricting subtype, Global PA, Joviality, and Self-Assurance decreased prior to and Self-Assurance increased following restrictive eating episodes. In contrast, Global PA and Self-Assurance increased prior to, but did not change following, restrictive eating episodes among individuals with AN binge eating/purging subtype. Results suggest that dietary restriction may function to mitigate guilt across AN subtypes and to enhance self-assurance among individuals with AN restricting subtype. (PsycINFO Database Record

Understanding Environmental and Contextual Influences of Physical Activity During First-Year University: The Feasibility of Using Ecological Momentary Assessment in the MovingU Study.

BackgroundIt is well established that drastic declines in physical activity (PA) occur during young adults’ transition into university; however, our understanding of contextual and environmental factors as it relates to young adults’ PA is limited.ObjectiveThe purpose of our study was to examine the feasibility of using wrist-worn accelerometers and the use of ecological momentary assessment (EMA) to assess the context and momentary correlates of PA on multiple occasions each day during first-year university.MethodsFirst-year university students were asked to participate in the study. The participants completed a brief questionnaire and were subsequently asked to wear an ActiGraph GT9X-Link accelerometer and respond to a series of EMA prompts (7/day) via their phones for 5 consecutive days.ResultsA total of 96 first-year university students with smartphones agreed to participate in the study (mean age 18.3 [SD 0.51]; n=45 females). Overall, there was good compliance for wearing the accelerometers, with 91% (78/86) of the participants having ≥2 days of ≥10 hours of wear time (mean=3.53 valid days). Students were generally active, averaging 10,895 steps/day (SD 3413) or 1123.23 activity counts/min (SD 356.10). Compliance to EMA prompts was less desirable, with 64% (55/86) of the participants having usable EMA data (responding to a minimum of ≥3 days of 3 prompts/day or ≥4 days of 2 prompts/day), and only 47% (26/55) of these participants were considered to have excellent EMA compliance (responding to ≥5 days of 4 prompts/day or ≥ 4 days of 5 prompts/day).ConclusionsThis study represents one of the first studies to use an intensive real-time data capture strategy to examine time-varying correlates of PA among first-year university students. These data will aim to describe the physical and social contexts in which PA occurs and examine the relationships between momentary correlates of PA among the first-year university students. Overall, current results suggest that wrist-worn accelerometers and EMA are feasible methods for data collection among the young adult population; however, more work is needed to understand how to improve upon compliance to a real-time data capture method such as EMA.

Anhedonia: Its Dynamic Relations With Craving, Negative Affect, and Treatment During a Quit Smoking Attempt

Research shows that abstinence from tobacco leads to a withdrawal-related decrement in responsivity to nondrug rewards (ie, anhedonia). However, it remains unclear how anhedonia relates to other key withdrawal symptoms and withdrawal-related constructs over time. We analyzed ecological momentary assessment data to examine whether a decrement in response to rewards during a 10-day period following quitting shows a pattern of associations with other variables (ie, treatment, tobacco dependence, negative affect, and craving) that is consistent with anhedonia being a tobacco withdrawal symptom. As part of a randomized controlled trial of smoking cessation therapies, 1122 adults (58% female) were assigned to: placebo (n = 131), bupropion (alone or with nicotine lozenge; n = 401), or nicotine replacement therapy (NRT; lozenge, patch, both; n = 590). Participants completed 4 ecological momentary assessments per day for 10 days postquit, resulting in 22 575 assessments. Time-varying effect modeling showed that anhedonia was significantly greater among those high in dependence relative to lower dependent smokers out to day 9 postquit. The placebo group showed elevated anhedonia immediately postquit, which fell to levels similar to the treatment groups by day 7. NRT effectively reduced anhedonia and its time-varying association with craving early in the quit attempt. The positive association between negative affect and anhedonia was moderate and stable over time for both active treatment groups. These results provide additional support that anhedonia following quitting smoking is a manifestation of the tobacco withdrawal syndrome. This study supported the hypothesis that diminished responsivity to nondrug rewards (ie, anhedonia) is a symptom of the tobacco withdrawal syndrome. Results showed that anhedonia: (1) was significantly associated with dependence, especially during the early postquit period when withdrawal was at its peak intensity; (2) showed significant time-varying associations with other withdrawal symptoms, especially craving; and (3) was significantly suppressed by agonist administration as was its association with craving over time.