Assessment of Alcohol Use in the Natural Environment

Predicting Completion of Ecological Momentary Assessments Among Substance-Using Women Experiencing Intimate Partner Violence

Noncompletion of ecological momentary assessment (EMA) surveys is a common issue and may yield bias in results if not properly handled. Using data observed at scheduled times as well as data retrieved later to fill missing responses, this study aims to investigate predictors of EMA completion, including demographic characteristics, time-related factors, and momentary experiences/behaviors. Data were from a 30-day EMA study including 145 women currently experiencing intimate partner violence (IPV) and using substances. The average rate of EMA completion was initially 51.4% at the scheduled times and increased to 72.6% after incorporating data from later-retrieved surveys. Participants who were younger, had more children, or had lower mean levels of negative affect dysregulation showed lower completion rates. At the momentary survey level, more days into the study and afternoon/evening reports (vs. morning reports) were associated with lower completion; lower levels of negative affect dysregulation, less smoking or alcohol use, and experiencing IPV were linked to lower momentary completion. Implications of the results for handling missing data in EMA are discussed and have important ramifications for future research, practice, and theory.

Social mobile sensing and problematic alcohol consumption: Insights from smartphone metadata

BACKGROUND

Alcohol is often consumed in a social context. We aim to investigate whether social mobile sensing is associated with real-world social interactions and alcohol consumption. In addition, we investigate how social restriction policies implemented during the COVID-19 pandemic have influenced these associations.

METHODS

We conducted a smartphone-based ecological momentary assessment (EMA) study for 7 days over a 213-day period from 8 August 2020 to 9 March 2021 in Germany, including both no-lockdown and lockdown stages. Participants used a smartphone application which passively collects data on social behavior (e.g., app usage, phone calls, SMS). Moreover, we assessed real-world social interactions and alcohol consumption via daily questionnaires.

RESULTS

We found that each one-hour increase in social media usage was associated with a 40.2% decrease in the average number of drinks consumed. Mediation analysis suggested that social media usage decreases alcohol intake through decreased real-world social interactions. Notably, we did not find that any significant influence of the lockdown stage on the association between social mobile sensing and alcohol intake.

CONCLUSIONS

Our study suggests that people who use more social media drink less, likely due to reduced face-to-face social interactions. This highlights the potential of social mobile sensing as an objective measure of social activity and its implications for understanding alcohol consumption behavior.

Endpoints for Pharmacotherapy Trials for Alcohol Use Disorder

Alcohol use disorder (AUD) is a debilitating disorder, yet currently approved pharmacotherapies to treat AUD are under-utilized. The three medications approved by the US Food and Drug Administration (FDA) for the indication of AUD are disulfiram, acamprosate, and naltrexone. The current landscape of pharmacotherapies for AUD suggests opportunities for improvement. Clinical trials investigating novel pharmacotherapies for AUD traditionally use abstinence-based drinking outcomes or no heavy drinking days as trial endpoints to determine the efficacy of pharmacotherapies. These outcomes are typically measured through patient self-report endorsements of their drinking. Apart from these traditional outcomes, there have been recent developments in novel endpoints for AUD pharmacotherapies. These novel endpoints include utilizing the World Health Organization (WHO) risk drinking level reductions to promote a harm-reduction endpoint rather than an abstinence-based endpoint. Additionally, in contrast to patient self-report measurements, biological markers of alcohol use may serve as objective endpoints in AUD pharmacotherapy trials. Lastly, the National Institute on Alcohol Abuse and Alcoholism (NIAAA) definition of recovery from AUD and patient-oriented outcomes offer new frameworks to consider endpoints associated with more than alcohol consumption itself, such as the provider-patient experiences with novel pharmacotherapies. These recent developments in new endpoints for AUD pharmacotherapies offer promising future opportunities for pharmacotherapy development, so long as validity and reliability measures are demonstrated for the endpoints. A greater breadth of endpoint utilization may better capture the complexity of AUD symptomatology.

Interpretations and experiences of subjective effects for alcohol alone and when combined with cannabis: A mixed-methods approach

Subjective effects generally describe the feelings one has when consuming substances. There are several tools available for measuring alcohol-related subjective effects but there are reasons to believe that effects are interpreted differently across participants. The assessment of alcohol-related subjective effects is further complicated by the fact that many people use other substances with alcohol, including cannabis. The present study used a mixed-methods approach to evaluate interpretations of 21 subjective effects used in common assessments among a college student sample (N = 99; primarily White [79%], Hispanic [60%] women [74%], 72% of which reported lifetime couse of alcohol and cannabis). We sought to (a) estimate the prevalence of each effect and the amount of alcohol/number of drinks (and, for those with simultaneous use, amount of cannabis/number of hits) required to experience each effect and (b) evaluate how participants interpreted each effect that they had ever experienced when drinking (for our sample who had used only alcohol) or when simultaneously using alcohol and cannabis (for our sample who had reported simultaneous use). Across both samples, we found that several effects were far more common than others and participants had varied interpretations of each subjective effect. Further, qualitative results demonstrated that participants interpreted some subjective effects in a way that differed from the original intention of the measure. Results suggest a degree of measurement error when using common subjective effects assessment tools. Findings lay the groundwork for standardized measures of subjective effects for simultaneous use and have implications for future real-world assessment and intervention work. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Daily and Momentary Associations Between Gender Minority Stress and Resilience With Alcohol Outcomes

BACKGROUND AND PURPOSE

Minority stressors have been linked with alcohol use among transgender and gender diverse (TGD); however, no ecological momentary assessment studies have examined daily links between minority stress and alcohol use specifically among TGD. This study examined gender minority stressors and resilience as predictors of same-day or momentary alcohol-related outcomes. Feasibility and acceptability of procedures were evaluated.

METHODS

Twenty-five TGD adults (mean age = 32.60, SD = 10.82; 88% White) were recruited Canada-wide and participated remotely. They completed 21 days of ecological momentary assessment with daily morning and random surveys (assessing alcohol outcomes, risk processes, gender minority stressors, resilience), and an exit interview eliciting feedback.

RESULTS

Gender minority stress had significant and positive within-person relationships with same-day alcohol use (incidence risk ratio (IRR) = 1.12, 95% confidence interval [CI] [1.02, 1.23]), alcohol-related harms (IRR = 1.14, 95% CI [1.02, 1.28]), and coping motives (IRR = 1.06, 95% CI [1.03, 1.08]), as well as momentary (past 30-min) alcohol craving (IRR = 1.32, 95% CI [1.18, 1.47]), coping motives (IRR = 1.35, 95% CI [1.21, 1.51]), and negative affect (IRR = 1.28, 95% CI [1.20, 1.36]). Gender minority stress indirectly predicted same-day drinking via coping motives (ab = 0.04, 95% CI [0.02, 0.08]). Resilience was positively associated with same-day alcohol use (IRR = 1.25, 95% CI [1.03, 1.51]) but not harms.

CONCLUSIONS

TGD adults may use alcohol to cope with gender minority stress, which can increase the risk for alcohol-related harms. Interventions are needed to eliminate gender minority stressors and support adaptive coping strategies.

Baseline protective behavioral strategy use predicts more moderate transdermal alcohol concentration dynamics and fewer negative consequences of drinking in young adults' natural settings

OBJECTIVE

Test whether frequent protective behavioral strategies (PBS) users report (a) fewer alcohol-related consequences and (b) less risky alcohol intoxication dynamics (measured via transdermal alcohol concentration [TAC] sensor "features") in daily life.

METHOD

Two hundred twenty-two frequently heavy-drinking young adults (Mage = 22.3 years) wore TAC sensors for 6 consecutive days. TAC features peak (maximum TAC), rise rate (speed of TAC increase), and area under the curve (AUC) were derived for each day. Negative alcohol-related consequences were measured in the morning after each self-reported drinking day. Past-year PBS use was measured at baseline.

RESULTS

Young adults reporting more frequent baseline PBS use showed (a) fewer alcohol-related consequences and (b) lower intoxication dynamics on average (less AUC, lower peaks, and slower rise rates). Limiting/stopping and manner of drinking PBS showed the same pattern of findings as the total score. Serious harm reduction PBS predicted fewer negative alcohol-related consequences, but not TAC features. Multilevel path models showed that TAC features peak and rise rate partially explained associations between PBS (total, limiting/stopping, and manner of drinking) and consequences. Independent contributions of PBS subscales were small and nonsignificant, suggesting that total PBS use was a more important predictor of risk/protection than the specific types of PBS used.

CONCLUSIONS

Young adults using more total PBS may experience fewer alcohol-related consequences during real-world drinking episodes in part through less risky intoxication dynamics (TAC features). Future research measuring PBS at the daily level is needed to formally test TAC features as day-level mechanisms of protection from acute alcohol-related consequences. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Integrating Alcohol Biosensors With Ecological Momentary Intervention (EMI) for Alcohol Use: a Synthesis of the Latest Literature and Directions for Future Research

Purpose of Review

Excessive alcohol use is a major public health concern. With increasing access to mobile technology, novel mHealth approaches for alcohol misuse, such as ecological momentary intervention (EMI), can be implemented widely to deliver treatment content in real time to diverse populations. This review summarizes the state of research in this area with an emphasis on the potential role of wearable alcohol biosensors in future EMI/just-in-time adaptive interventions (JITAI) for alcohol use.

Recent Findings

JITAI emerged as an intervention design to optimize the delivery of EMI for various health behaviors including substance use. Alcohol biosensors present an opportunity to augment JITAI/EMI for alcohol use with objective information on drinking behavior captured passively and continuously in participants' daily lives, but no prior published studies have incorporated wearable alcohol biosensors into JITAI for alcohol-related problems. Several methodological advances are needed to accomplish this goal and advance the field. Future research should focus on developing standardized data processing, analysis, and interpretation methods for wrist-worn biosensor data. Machine learning algorithms could be used to identify risk factors (e.g., stress, craving, physical locations) for high-risk drinking and develop decision rules for interpreting biosensor-derived transdermal alcohol concentration (TAC) data. Finally, advanced trial design such as micro-randomized trials (MRT) could facilitate the development of biosensor-augmented JITAI.

Summary

Wrist-worn alcohol biosensors are a promising potential addition to improve mHealth and JITAI for alcohol use. Additional research is needed to improve biosensor data analysis and interpretation, build new machine learning models to facilitate integration of alcohol biosensors into novel intervention strategies, and test and refine biosensor-augmented JITAI using advanced trial design.

Signal processing and machine learning with transdermal alcohol concentration to predict natural environment alcohol consumption

Wrist-worn alcohol biosensors continuously and discreetly record transdermal alcohol concentration (TAC) and may allow alcohol researchers to monitor alcohol consumption in participants' natural environments. However, the field lacks established methods for signal processing and detecting alcohol events using these devices. We developed software that streamlines analysis of raw data (TAC, temperature, and motion) from a wrist-worn alcohol biosensor (BACtrack Skyn) through a signal processing and machine learning pipeline: biologically implausible skin surface temperature readings (< 28°C) were screened for potential device removal and TAC artifacts were corrected, features that describe TAC (e.g., rise duration) were calculated and used to train models (random forest and logistic regression) that predict self-reported alcohol consumption, and model performances were measured and summarized in autogenerated reports. The software was tested using 60 Skyn data sets recorded during 30 alcohol drinking episodes and 30 nonalcohol drinking episodes. Participants (N = 36; 13 with alcohol use disorder) wore the Skyn during one alcohol drinking episode and one nonalcohol drinking episode in their natural environment. In terms of distinguishing alcohol from nonalcohol drinking, correcting artifacts in the data resulted in 10% improvement in model accuracy relative to using raw data. Random forest and logistic regression models were both accurate, correctly predicting 97% (58/60; AUC-ROCs = 0.98, 0.96) of episodes. Area under TAC curve, rise duration of TAC curve, and peak TAC were the most important features for predictive accuracy. With promising model performance, this protocol will enhance the efficiency and reliability of TAC sensors for future alcohol monitoring research. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Predictive utility of the P3 event-related potential (ERP) response to alcohol cues for ecologically assessed alcohol craving and use

Neural measures of alcohol cue incentive salience have been associated with retrospective reports of riskier alcohol use behaviour and subjective response profiles. This study tested whether the P3 event-related potential (ERP) elicited by alcohol-related cues (ACR-P3) can forecast alcohol use and craving during real-world drinking episodes. Participants (N = 262; Mage  = 19.53; 56% female) completed a laboratory task in which they viewed images of everyday objects (Neutral), non-alcohol drinks (NonAlc) and alcohol beverages (Alc) while EEG was recorded and then completed a 21-day ecological momentary assessment (EMA) protocol in which they recorded alcohol craving and consumption. Anthropometrics were used to derive estimated blood alcohol concentration (eBAC) throughout drinking episodes. Multilevel modelling indicated positive associations between P3 amplitudes elicited by all stimuli and within-episode alcohol use measures (e.g., eBAC, cumulative drinks). Focal follow-up analyses indicated a positive association between AlcP3 amplitude and eBAC within episodes: Larger AlcP3 was associated with a steeper rise in eBAC. This association was robust to controlling for the association between NonAlcP3 and eBAC. AlcP3 also was positively associated with episode-level measures (e.g., max drinks, max eBAC). There were no associations between any P3 variables and EMA-based craving measures. Thus, individual differences in neural measures of alcohol cue incentive salience appear to predict the speed and intensity of alcohol consumption but not reports of craving during real-world alcohol use episodes.

Involuntary social isolation and alcohol consumption: an ecological momentary assessment in Germany amid the COVID-19 pandemic

AIMS

Alcohol consumption often occurs in a social setting, which was affected by social distancing measures amid the coronavirus disease-2019 (COVID-19) pandemic. In this study, we examine how involuntary social isolation (i.e. comparing a no-lockdown stage with a lockdown stage) affects the association between loneliness, social activities, and drinking behavior.

METHOD

We performed an ecological momentary assessment eight times per day for 7 days amid the COVID-19 pandemic in Germany. We recruited 280 participants and assessed their trait loneliness, daily state loneliness, social activities, and drinking behaviors.

RESULTS

We found that a lockdown condition moderates the association between trait and daily state loneliness and alcohol consumption. During a lockdown stage, trait loneliness was positively associated, whereas state loneliness was negatively associated with alcohol consumption. During a no-lockdown stage, trait and state loneliness were both negatively associated with alcohol consumption. For both no-lockdown and lockdown stages, duration of social interaction, male gender, and weekends was positively associated with alcohol consumption.

CONCLUSION

Our study suggests that an involuntary social isolation condition (i.e. a lockdown stage) changes how trait loneliness is associated with alcohol consumption.

Detection of Alcohol Intoxication Using Voice Features: A Controlled Laboratory Study

OBJECTIVE

Devices such as mobile phones and smart speakers could be useful to remotely identify voice alterations associated with alcohol intoxication that could be used to deliver just-in-time interventions, but data to support such approaches for the English language are lacking. In this controlled laboratory study, we compare how well English spectrographic voice features identify alcohol intoxication.

METHOD

A total of 18 participants (72% male, ages 21-62 years) read a randomly assigned tongue twister before drinking and each hour for up to 7 hours after drinking a weight-based dose of alcohol. Vocal segments were cleaned and split into 1-second windows. We built support vector machine models for detecting alcohol intoxication, defined as breath alcohol concentration > .08%, comparing the baseline voice spectrographic signature to each subsequent timepoint and examined accuracy with 95% confidence intervals (CIs).

RESULTS

Alcohol intoxication was predicted with an accuracy of 98% (95% CI [97.1, 98.6]); mean sensitivity = .98; specificity = .97; positive predictive value = .97; and negative predictive value = .98.

CONCLUSIONS

In this small, controlled laboratory study, voice spectrographic signatures collected from brief recorded English segments were useful in identifying alcohol intoxication. Larger studies using varied voice samples are needed to validate and expand models.

Development and validation of a model for measuring alcohol consumption from transdermal alcohol content data among college students

BACKGROUND AND AIMS

Transdermal alcohol content (TAC) data collected by wearable alcohol monitors could potentially contribute to alcohol research, but raw data from the devices are challenging to interpret. We aimed to develop and validate a model using TAC data to detect alcohol drinking.

DESIGN

We used a model development and validation study design.

SETTING

Indiana, USA PARTICIPANTS: In March to April 2021, we enrolled 84 college students who reported drinking at least once a week (median age = 20 years, 73% white, 70% female). We observed participants' alcohol drinking behavior for 1 week.

MEASUREMENTS

Participants wore BACtrack Skyn monitors (TAC data), provided self-reported drinking start times in real time (smartphone app) and completed daily surveys about their prior day of drinking. We developed a model using signal filtering, peak detection algorithm, regression and hyperparameter optimization. The input was TAC and outputs were alcohol drinking frequency, start time and magnitude. We validated the model using daily surveys (internal validation) and data collected from college students in 2019 (external validation).

FINDINGS

Participants (N = 84) self-reported 213 drinking events. Monitors collected 10 915 hours of TAC. In internal validation, the model had a sensitivity of 70.9% (95% CI = 64.1%-77.0%) and a specificity of 73.9% (68.9%-78.5%) in detecting drinking events. The median absolute time difference between self-reported and model-detected drinking start times was 59 min. Mean absolute error (MAE) for the reported and detected number of drinks was 2.8 drinks. In an exploratory external validation among five participants, number of drinking events, sensitivity, specificity, median time difference and MAE were 15%, 67%, 100%, 45 minutes and 0.9 drinks, respectively. Our model's output was correlated with breath alcohol concentration data (Spearman's correlation [95% CI] = 0.88 [0.77, 0.94]).

CONCLUSION

This study, the largest of its kind to date, developed and validated a model for detecting alcohol drinking using transdermal alcohol content data collected with a new generation of alcohol monitors. The model and its source code are available as Supporting Information (https://osf.io/xngbk).

Assessing real-time positive subjective effects of alcohol using high-resolution ecological momentary assessment in risky versus light drinkers

BACKGROUND

High-resolution ecological momentary assessment (HR-EMA) can assess acute alcohol responses during naturalistic heavy drinking episodes. The goal of this study was to use HR-EMA to examine drinking behavior and subjective responses to alcohol in risky drinkers (moderate-severe alcohol use disorder [MS-AUD], heavy social drinkers [HD]) and light drinkers (LD). We expected that risky drinkers would endorse greater alcohol stimulation and reward, with lower sedation, than LD, even when controlling for amount of alcohol consumed.

METHODS

Participants (N = 112; 54% male, M ± SD age = 27.2 ± 4.2 years) completed smartphone-based HR-EMA during one typical alcohol drinking occasion and one non-alcohol-drinking occasion in their natural environment. Participants were prompted to complete next-day surveys that assessed drinking-related outcomes, study acceptability, and safety.

RESULTS

HR-EMA prompt completion rates were excellent (92% and 89% for the alcohol and nonalcohol episodes, respectively). The MS-AUD group consumed the most alcohol with the highest estimated blood alcohol concentration (eBAC) by the end of the alcohol drinking episode (0.14 g/dL) versus LD (0.02 g/dL), with HD intermediate (0.10 g/dL). Relative to LD, MS-AUD and HD endorsed greater positive effects of alcohol (stimulation, liking, and wanting).

CONCLUSIONS

This study is the first to use HR-EMA to measure and compare real-world acute alcohol responses across diverse drinker subgroups, including persons with MS-AUD. Results demonstrate that risky drinkers experience heightened pleasurable effects measured in real-time during natural-environment alcohol responses. Rather than drinking excessively to eventually achieve desirable subjective effects, risky drinkers show sensitivity to positive alcohol effects throughout a heavy drinking episode.

Agreement between momentary and retrospective reports of cannabis use and alcohol use: Comparison of ecological momentary assessment and timeline followback indices

OBJECTIVE

This study compares three methods of cannabis and of alcohol use assessment in a sample of regular cannabis users: (a) ecological momentary assessment (EMA) repeated momentary surveys aggregated to the daily level, (b) EMA morning reports (MR) where participants reported on their total use from the previous day, and (c) retrospective timeline followback (TLFB) interviews covering the same period of time as the EMA portion of the study. We assessed the overall correspondence between these methods in terms of cannabis and alcohol use occasions and also investigated predictors of agreement between methods.

METHOD

Forty-nine individuals aged 18-50 (Mage = 24.49, 49% female, 84% White) who reported regular cannabis use completed a 14-day EMA study. At the end of the EMA period, participants returned to the laboratory to complete a TLFB (administered via computer) corresponding to the same dates of the EMA period.

RESULTS

Daily aggregated EMA and TLFB reports showed a low to modest agreement for both alcohol and cannabis use. Overall, agreement between EMA and MR was better than agreement between EMA and TLFB, likely because less retrospection is required when only reporting on behavior from the previous day. Quantity and frequency of use differentially predicted agreement across reporting methods when assessing alcohol compared to cannabis. When reporting cannabis use, but not alcohol use, individuals who used more demonstrated higher agreement between EMA and TLFB.

CONCLUSIONS

Results suggest that retrospective reporting methods assessing alcohol and cannabis should not be considered a direct "substitute" for momentary or daily assessments. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Acceptability and validity of using the BACtrack skyn wrist-worn transdermal alcohol concentration sensor to capture alcohol use across 28 days under naturalistic conditions - A pilot study

Wrist-worn transdermal alcohol concentration (TAC) sensors have the potential to provide detailed information about day-level features of alcohol use but have rarely been used in field-based research or in early adulthood (i.e., 26-40 years) alcohol users. This pilot study assessed the acceptability, user burden, and validity of using the BACtrack Skyn across 28 days in individuals' natural settings. Adults aged 26-37 (N = 11, Mage = 31.2, 55% female, 73% non-Hispanic white) participated in a study including retrospective surveys, a 28-day field protocol wearing Skyn and SCRAM sensors and completing ecological momentary assessments (EMA) of alcohol use and duration (daily morning reports and participant-initiated start/stop drinking EMAs), and follow-up interviews. Day-level features of alcohol use extracted from self-reports and/or sensors included drinks consumed, estimated Blood Alcohol Concentration (eBAC), drinking duration, peak TAC, area under the curve (AUC), rise rate, and fall rate. Repeated-measures correlations (rrm) tested within-person associations between day-level features of alcohol use from the Skyn versus self-report or the SCRAM. Participants preferred wearing the Skyn over the SCRAM [t (10) = -6.79, p < .001, d = 2.74]. Skyn data were available for 5614 (74.2%) out of 7566 h, with 20.7% of data lost due to syncing/charging issues and 5.1% lost due to device removal. Skyn agreement for detecting drinking days was 55.5% and 70.3% when compared to self-report and the SCRAM, respectively. Correlations for drinking intensity between self-report and the Skyn were 0.35 for peak TAC, 0.52 for AUC, and 0.30 for eBAC, which were smaller than correlations between self-report and SCRAM, at 0.78 for peak TAC, 0.79 for AUC, and 0.61 for eBAC. Correlations for drinking duration were larger when comparing self-report to the Skyn (rrm = 0.36) versus comparing self-report to the SCRAM (rrm = 0.31). The Skyn showed moderate-to-large, significant correlations with the SCRAM for peak TAC (rrm = 0.54), AUC (rrm = 0.80), and drinking duration (rrm = 0.63). Our findings support the acceptability and validity of using the Skyn for assessing alcohol use across an extended time frame (i.e., 28 days) in individuals' natural settings, and for providing useful information about day-level features of alcohol use.

Drinking context, alcohol use, and subjective responses during binge drinking episodes measured by high-resolution ecological momentary assessment (HR-EMA)

OBJECTIVE

Subjective responses to alcohol play a key role in the development and maintenance of risky drinking and alcohol use disorder (AUD). The social and environmental context where drinking occurs may moderate alcohol's subjective effects, but ecologically valid studies of these associations are limited. The present study used high-resolution ecological momentary assessment (HR-EMA) targeting real-world binge drinking episodes to examine associations among drinking context, alcohol consumption, and subjective responses to alcohol.

METHOD

Young adult heavy drinkers (N = 61; 57% male) completed two smartphone-based, 3-hr HR-EMA of drinking context (social context and location), alcohol use, and subjective responses (alcohol stimulation, sedation, feeling, liking, and wanting more). Analyses examined the associations between drinking context and subjective alcohol responses, accounting for demographic characteristics and individual differences in alcohol consumption.

RESULTS

Most (85%) participants reported binge drinking during real-world drinking events. Estimated blood alcohol concentration (eBAC) and alcohol stimulation and reward (liking, wanting) were greater when participants drank with others (vs. alone) and in a bar/restaurant (vs. other location). Sedation was higher when drinking alone versus with others.

CONCLUSIONS

The present study extends prior laboratory-based research and shows that subjective responses during naturalistic binge drinking episodes may be influenced by drinking context. Drinking with others and in bars and restaurants may increase alcohol consumption, enhance alcohol's rewarding effects, and lead to more alcohol-related harm in at-risk drinkers. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Correspondence between alcohol use measured by a wrist-worn alcohol biosensor and self-report via ecological momentary assessment over a 2-week period

BACKGROUND

Transdermal alcohol biosensors measure alcohol use continuously, passively, and non-invasively. There is little field research on the Skyn biosensor, a new-generation, wrist-worn transdermal alcohol biosensor, and little evaluation of its sensitivity and specificity and the day-level correspondence between transdermal alcohol concentration (TAC) and number of self-reported drinks.

METHODS

Participants (N = 36; 61% male, M age  = 34.3) wore the Skyn biosensor and completed ecological momentary assessment (EMA) surveys about their alcohol use over 2 weeks. A total of 497 days of biosensor and EMA data were collected. Skyn-measured drinking episodes were defined by TAC > 5 μg/L. Skyn data were compared to self-reported drinking to calculate sensitivity and specificity (for drinking day vs. nondrinking day). Generalized estimating equations models were used to evaluate the correspondence between TAC features (peak TAC and TAC-area under the curve (AUC)) and number of drinks. Individual-level factors (sex, age, race/ethnicity, body mass index, human immunodeficiency virus status, and hazardous drinking) were examined to explore associations with TAC controlling for number of drinks.

RESULTS

Using a minimum TAC threshold of 5 μg/L plus coder review, the biosensor had sensitivity of 54.7% and specificity of 94.6% for distinguishing drinking from nondrinking days. Without coder review, the sensitivity was 78.1% and the specificity was 55.2%. Peak TAC (β = 0.92, p < 0.0001) and TAC-AUC (β = 1.60, p < 0.0001) were significantly associated with number of drinks. Females had significantly higher TAC levels than males for the same number of drinks.

CONCLUSIONS

Skyn-derived TAC can be used to measure alcohol use under naturalistic drinking conditions, additional research is needed to accurately identify drinking episodes based on Skyn TAC readings.

Alcohol craving in the natural environment: Moderating roles of cue exposure, drinking, and alcohol sensitivity

Effects of cue exposure and alcohol consumption (e.g., priming doses) on craving for alcohol have been examined in largely separate literature, limiting what is known about their potential interaction. Individuals with low alcohol sensitivity, a known risk factor for alcohol use disorder (AUD), exhibit stronger cue-elicited craving than their higher-sensitivity (HS) peers in both laboratory and real-world contexts. Here, underage drinkers (N = 155) completed a 21-day ecological momentary assessment (EMA) protocol in which they recorded exposure to alcohol cues and levels of craving during both nondrinking and postdrinking moments. Multilevel modeling detected a significant interaction of cue exposure and postdrinking status on craving. Cue-induced craving was increased in postdrinking moments compared to nondrinking moments. Contrary to prediction, cue-elicited increase in craving during nondrinking moments was stronger in participants reporting higher sensitivity to alcohol. In the presence of cues, lower sensitivity was robustly related to craving intensity in the postdrinking state but unrelated to craving during nondrinking moments. Craving during drinking episodes in the natural environment is magnified by the presence of alcohol cues, potentially contributing to the maintenance or acceleration of drinking episodes. Moreover, lower-sensitivity drinkers may be particularly susceptible to the combined effects of cue exposure and postdrinking status on alcohol craving. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Blood Phosphatidylethanol (PEth) Concentrations following Intensive Use of an Alcohol-based Hand Sanitizer

Alcohol use disorders are prevalent in the USA and throughout the world. Monitoring for alcohol abstinence is useful in several clinical and forensic contexts. The direct alcohol biomarkers have the requisite sensitivity and specificity for abstinence monitoring. The relatively new direct biomarker phosphatidylethanol (PEth), measured in blood, is gaining increasing acceptance in monitoring abstinence from beverage alcohol consumption, but there remains little research addressing the potential for PEth formation consequent to incidental alcohol exposures. In the midst of the coronavirus disease 2019 pandemic, high-alcohol content hand sanitizer is a particularly important source of nonbeverage alcohol exposure. To assess the extent of alcohol absorption and subsequent formation of blood PEth related to intensive use of high alcohol content hand sanitizer, we recruited 15 participants to use a 70% ethyl alcohol-based hand sanitizer 24-100 times daily, for 12-13 consecutive days. Blood was analyzed for PEth 16:0/18:1 by liquid chromatography--tandem mass spectrometry. Our hypothesis that blood PEth concentrations would fail to reach a 20 ng/mL threshold was confirmed. This work adds to the nascent literature on the effects of incidental alcohol exposures on blood PEth formation.

Examining new-generation transdermal alcohol biosensor performance across laboratory and field contexts

BACKGROUND

Wrist-worn transdermal alcohol sensors have the potential to change how alcohol consumption is measured. However, hardware and data analytic challenges associated with transdermal sensor data have kept these devices from widespread use. Given recent technological and analytic advances, this study provides an updated account of the performance of a new-generation wrist-worn transdermal sensor in both laboratory and field settings.

METHODS

This work leverages machine learning models to convert transdermal alcohol concentration data into estimates of Breath Alcohol Concentration (BrAC) in a large-scale laboratory sample (N = 256, study 1) and a pilot field sample (N = 27, study 2). Specifically, in both studies, the accuracy of the translation is evaluated by comparing BAC estimates yielded by BACtrack Skyn to real-time breathalyzer measurements collected in the laboratory and in the field.

RESULTS

The newest version of the Skyn device demonstrates a substantially lower error rate than older hand-assembled prototypes (0% to 7% vs. 29% to 53%, respectively). On average, real-time estimates of BrAC yielded by these transdermal sensors are within 0.007 of true BAC readings in the laboratory context and within 0.019 of true BrAC readings in the field. In both contexts, the distance between true and estimated BrAC was larger when only alcohol episodes were examined (laboratory = 0.017; field = 0.041). Finally, results of power-law-curve projections indicate that, given their accuracy, transdermal BrAC estimates in real-world contexts have the potential to improve markedly (>25%) with adequately sized datasets for model training.

CONCLUSION

Findings from this study indicate that the latest version of the transdermal wrist sensor holds promise for the accurate assessment of alcohol consumption in field contexts. A great deal of additional work is needed to provide a full picture of the utility of these devices, including research with large participant samples in field contexts.

Alcohol consumption and pregnancy in American Indian and Alaska Native women: A scoping review of the literature

American Indian and Alaska Native communities have diverse cultures, histories, and contemporary experiences. Grouping them together masks the differences in health and lifestyle behaviors, chronic disease rates, and health outcomes among them. This is particularly true for data on drinking during pregnancy among American Indian and Alaska Native women. The goal of this article is to describe how generalizing findings from data gathered from often small, geographically specific samples, combined with inferior research methodologies, has led to misunderstandings about drinking among preconceptual and pregnant American Indian and Alaska Native women. We conducted a scoping review using PubMed and the "PCC mnemonic" (population, concept, and context) as our guide. Our search terms included the population (American Indian and Alaska Native women), concept (alcohol), and context (immediately before or during pregnancy) and focused on PubMed articles in the United States. Using these search terms, we uncovered a total of 38 publications and eliminated 19, leaving 19 for review. Methodologically (i.e. how data were collected), we found most previous research on prenatal or preconceptual alcohol use with American Indian and Alaska Native women used retrospective data collection. We also assessed who data were collected from and noted two groups: studies that sampled higher-risk women and those that focused on American Indian and Alaska Native women in specific geographic areas. Restricting data collection to higher-risk American Indian and Alaska Native women or conducting small studies in specific geographic areas has generated an incomplete and inaccurate picture of American Indian and Alaska Native women as a whole as well as those who consume alcohol. Data from select groups of American Indian and Alaska Native women may overestimate the true prevalence of drinking during pregnancy among this population. Updated and accurate data on drinking during pregnancy are urgently needed to inform the development of interventions and prevention efforts.

Acceptability and Feasibility of Wearable Transdermal Alcohol Sensors: Systematic Review

BACKGROUND

Transdermal alcohol sensors (TASs) have the potential to be used to monitor alcohol consumption objectively and continuously. These devices can provide real-time feedback to the user, researcher, or health professional and measure alcohol consumption and peaks of use, thereby addressing some of the limitations of the current methods, including breathalyzers and self-reports.

OBJECTIVE

This systematic review aims to evaluate the acceptability and feasibility of the currently available TAS devices.

METHODS

A systematic search was conducted in CINAHL, EMBASE, Google Scholar, MEDLINE, PsycINFO, PubMed, and Scopus bibliographic databases in February 2021. Two members of our study team independently screened studies for inclusion, extracted data, and assessed the risk of bias. The study's methodological quality was appraised using the Mixed Methods Appraisal Tool. The primary outcome was TAS acceptability. The secondary outcome was feasibility. The data are presented as a narrative synthesis.

RESULTS

We identified and analyzed 22 studies. Study designs included laboratory- and ambulatory-based studies, mixed designs, randomized controlled trials, and focus groups, and the length the device was worn ranged from days to weeks. Although views on TASs were generally positive with high compliance, some factors were indicated as potential barriers and there are suggestions to overcome these.

CONCLUSIONS

There is a lack of research investigating the acceptability and feasibility of TAS devices as a tool to monitor alcohol consumption in clinical and nonclinical populations. Although preliminary evidence suggests their potential in short-term laboratory-based studies with volunteers, more research is needed to establish long-term daily use with other populations, specifically, in the clinical and the criminal justice system.

TRIAL REGISTRATION

PROSPERO CRD42021231027; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=231027.

Validating transdermal alcohol biosensors: a meta-analysis of associations between blood/breath-based measures and transdermal alcohol sensor output

BACKGROUND AND AIMS

Transdermal alcohol sensors carry immense promise for the continuous assessment of drinking but are inconsistent in detecting more fine-grained indicators of alcohol consumption. Prior studies examining associations between transdermal alcohol concentration (TAC) and blood/breath alcohol concentration (BAC) have yielded highly variable correlations and lag times. The current review aimed to synthesize transdermal validation studies, aggregating results from more than three decades of research to characterize the validity of transdermal sensors for assessing alcohol consumption.

METHODS

Databases were searched for studies listed prior to 1 March 2022 that examined associations between transdermal alcohol sensor output and blood and breath-based alcohol measures, resulting in 31 primarily laboratory-derived participant samples (27 precise effect sizes) including both healthy and clinical populations. Correlation coefficients and lag times were pooled using three-level random-effects meta-regression. Independent raters coded study characteristics, including the body position of transdermal sensors (ankle- versus arm/hand/wrist-worn device) and methodological bias (e.g. missing data).

RESULTS

Analyses revealed that, in this primarily laboratory-derived sample of studies, the average correlation between TAC and BAC was large in magnitude [r = 0.87, 95% confidence interval (CI) = 0.80, 0.93], and TAC lagged behind BAC by an average of 95.90 minutes (95% CI = 55.50, 136.29). Device body position significantly moderated both TAC-BAC correlation (b = 0.11, P = 0.009) and lag time (b = -69.41, P < 0.001). Lag times for ankle-worn devices were approximately double those for arm/hand/wrist-worn devices, and TAC-BAC correlations also tended to be stronger for arm/hand/wrist-worn sensors.

CONCLUSIONS

This meta-analysis indicates that transdermal alcohol sensors perform strongly in assessing blood/breath alcohol concentration under controlled conditions, with particular promise for the newer generation of wrist-worn devices.

Alcohol demand as a predictor of drinking behavior in the natural environment

BACKGROUND AND AIMS

Alcohol demand, a measure of alcohol's reinforcing value, is associated with greater alcohol consumption and alcohol-related problems. Although alcohol demand has primarily been evaluated as a 'trait-like', individual difference measure, recent evidence indicates that demand exhibits meaningful short-term fluctuations. We aimed to determine whether moment-to-moment fluctuations in alcohol demand in individuals' natural drinking environments predicted drinking occurrence, drinking continuation, and drinking quantity.

DESIGN

Observational study.

SETTING

Individuals' natural drinking environments in Columbia, Missouri, USA.

PARTICIPANTS

Eighty-nine young adults (56% female; mean age = 24.8) participated from November 2018 to October 2020. Participants reported 14.5 drinking days [standard deviation (SD = 8.1)] and 4.1 drinks per occasion (SD = 2.5) during ecological momentary assessment (EMA).

MEASUREMENTS

Participants completed the alcohol purchase task at baseline. Following this, participants reported on their alcohol demand (breakpoint, O_max , intensity) and drinking behavior during EMA at daily, timed prompts from 6 p.m. to 2 a.m. They provided breathalyzer samples using a BACtrack Mobile® Pro. Models tested concurrent and prospective (lagged) associations between alcohol demand and drinking occurrence and drinking continuation after drinking initiation. Additional models tested concurrent associations between demand and breath alcohol concentrations (BrACs).

FINDINGS

Higher alcohol demand was associated with higher odds of drinking and continued drinking for all demand indices at the momentary [odds ratio (OR) = 1.27-1.56, ps ≤ 0.03] and day-level (OR = 2.14-3.39, ps < 0.001). Additionally, lagged demand predicted higher odds of drinking occurrence and continuation at the following prompt (OR = 1.32-1.53, ps ≤ 0.004). Higher alcohol demand was associated with higher BrACs at the momentary (bs = 0.0011-0.0026, ps ≤ 0.03) and day-level (bs = 0.0053-0.0062, ps < 0.001). At the person-level, findings varied depending on the demand measure.

CONCLUSIONS

Alcohol demand appears to be associated with both when and how much individuals drink in their natural drinking environments. Elevations in alcohol demand appear to be associated with increased likelihood of drinking and continuing to drink, and greater total alcohol consumption, both within and across drinking days.

Accuracy of Wearable Transdermal Alcohol Sensors: Systematic Review

BACKGROUND

There are a range of wearable transdermal alcohol sensors that are available and are being developed. These devices have the potential to monitor alcohol consumption continuously over extended periods in an objective manner, overcoming some of the limitations of other alcohol measurement methods (blood, breath, and urine).

OBJECTIVE

The objective of our systematic review was to assess wearable transdermal alcohol sensor accuracy.

METHODS

A systematic search of the CINAHL, Embase, Google Scholar, MEDLINE, PsycINFO, PubMed, and Scopus bibliographic databases was conducted in February 2021. In total, 2 team members (EB and SH) independently screened studies for inclusion, extracted data, and assessed the risk of bias. The methodological quality of each study was appraised using the Mixed Methods Appraisal Tool. The primary outcome was transdermal alcohol sensor accuracy. The data were presented as a narrative synthesis.

RESULTS

We identified and analyzed 32 studies. Study designs included laboratory, ambulatory, and mixed designs, as well as randomized controlled trials; the length of time for which the device was worn ranged from days to weeks; and the analyzed sample sizes ranged from 1 to 250. The results for transdermal alcohol concentration data from various transdermal alcohol sensors were generally found to positively correlate with breath alcohol concentration, blood alcohol concentration, and self-report (moderate to large correlations). However, there were some discrepancies between study reports; for example, WrisTAS sensitivity ranged from 24% to 85.6%, and specificity ranged from 67.5% to 92.94%. Higher malfunctions were reported with the BACtrack prototype (16%-38%) and WrisTAS (8%) than with SCRAM (2%); however, the former devices also reported a reduced time lag for peak transdermal alcohol concentration values when compared with SCRAM. It was also found that many companies were developing new models of wearable transdermal alcohol sensors.

CONCLUSIONS

As shown, there is a lack of consistency in the studies on wearable transdermal alcohol sensor accuracy regarding study procedures and analyses of findings, thus making it difficult to draw direct comparisons between them. This needs to be considered in future research, and there needs to be an increase in studies directly comparing different transdermal alcohol sensors. There is also a lack of research investigating the accuracy of transdermal alcohol sensors as a tool for monitoring alcohol consumption in clinical populations and use over extended periods. Although there is some preliminary evidence suggesting the accuracy of these devices, this needs to be further investigated in clinical populations.

TRIAL REGISTRATION

PROSPERO CRD42021231027; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=231027.

Measuring subjective alcohol effects in daily life using contemporary young adult language

Young adults' subjective feelings of alcohol's effects are a key predictor of engagement in risky behavior such as deciding whether to drive after drinking. To best inform prevention messaging and tailor intervention techniques that target high-risk drinking, it is critical that our measurement best captures subjective feelings. Standard sliding scales (0-100 rating of, "how drunk do you feel?") may have some challenges with distinguishing between levels of subjective responses to alcohol. The current daily diary study compared the utility of the standard sliding scale to a newly developed sliding scale that uses contemporary, crowd-sourced language from young adults as evenly spaced anchors (slightly buzzed, tipsy/"happy," drunk, and wasted) along a continuum of subjective effects of alcohol. Participants were 154 young adult substance users (58% women) who completed up to 14 consecutive daily reports of their substance use behavior. The four-anchored sliding scale performed similarly well as the standard scale in predicting alcohol use outcomes while showing the advantages of recording higher mean values/standard deviations and demonstrating that participants used the anchors to denote varying degrees of subjective effects. Findings suggest that the four-anchored subjective alcohol effects sliding scale is a viable alternative to the standard scale. By providing evenly spaced anchors that reflect incremental differences in language young adults use to describe their subjective states, the proposed scale may provide a guide for participants to indicate how they feel after drinking and may better capture variability in alcohol's effects. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Online Crowdsourcing as a Quasi-Experimental Method for Collecting Data on the Perpetration of Alcohol-Related Partner Aggression

Cross-sectional survey, prospective, and experimental data have been evaluated to better understand the role of alcohol as a contributing cause of intimate partner aggression. Laboratory-based alcohol administration studies provide controlled data regarding causality, but the use of this methodology lacks ecological validity and has been hampered by rigorous procedural and financial demands. Online crowdsourcing is an emerging pseudoexperimental methodology with low costs, rapid data collection, access to diverse populations, greater ecological validity, and the potential to facilitate prolific research to supplement the chronic scarcity of experimental data. The current rapid review first summarizes prior methodological approaches to investigating the proximal influence of alcohol on partner aggression, then reviews prior crowdsourcing research in the disparate areas of alcohol and partner aggression, then describes aggression paradigms that may be readily adapted to online administration. We conclude by introducing recommendations for future quasi-experimental research investigating alcohol-related partner aggression research using the online crowdsourcing methodology. Initial evidence suggests that online crowdsourcing may yield appropriate samples and that existing paradigms may be adapted to rapidly, efficiently, and ethically supplement experimental alcohol-related partner aggression research.

Trajectories of state impulsivity domains before and after alcohol consumption in the naturalistic environment

BACKGROUND AND AIMS

Studies have demonstrated that ecological momentary assessment (EMA) can effectively capture within-person variations in impulsive states and that this relates to alcohol use. The current study aimed to examine the daily trajectories of five facets of impulsivity prior to and following drinking initiation. Additionally, we explored how race, sex, baseline trait impulsivity facets, and ADHD may moderate this relation.

DESIGN AND SETTING

EMA was used to collect real-time data at 6 semi-random time points and self-initiated reports of drinking onset throughout the day over a 10-day period Measurements Five state and trait impulsivity facets were assessed via the UPPS-P. Naturalistic alcohol use, ADHD history, and demographic characteristics were also assessed PARTICIPANTS: Participants were 135 adult drinkers from a larger study examining alcohol response for Black and White adults with and without a history of childhood ADHD FINDINGS: Generalized estimating equations showed that the linear trajectory of negative urgency significantly increased prior to drinking. Following drinking initiation, the linear trajectory of sensation seeking significantly decreased. There was not significant change in the trajectories of positive urgency, lack of premeditation and lack of perseverance before or after drinking initiation. Additionally, race and ADHD history moderated the trajectory of sensation seeking and race moderated the trajectory of lack of planning.

CONCLUSIONS

Findings highlight the possibility of identifying proximal changes in impulsivity facets prior to and after initiation of drinking. Results can be used to inform real-time interventions that target risk periods to ultimately decrease alcohol use.

Alcohol craving and withdrawal at treatment entry prospectively predict alcohol use outcomes during outpatient treatment

OBJECTIVE

Chronic alcohol use increases risk of alcohol craving and withdrawal symptoms (AW) as well as abstinence-related distress symptoms, in those entering alcohol use disorder (AUD) treatment. Here, we examined whether AW and alcohol craving in AUD patients entering outpatient treatment prospectively predicts future heavy drinking days/week (HDD) and additional alcohol use outcomes during 8-weeks of outpatient treatment, and their relationship to abstinence symptoms of depression, anxiety and sleep difficulties.

METHODS

Participants were 80 treatment-seeking adults with current DSM-5 AUD (39% female; 43% White; 20-60 years) who completed assessments of AW and alcohol craving and also alcohol abstinence symptoms of depression, anxiety, and sleep quality at treatment intake. Participants were prospectively followed using daily diaries for alcohol intake during 8-week of standardized weekly relapse prevention counseling to support recovery.

RESULTS

After accounting for demographic and pre-treatment alcohol use, greater alcohol craving at treatment entry predicted higher HDD (p < .013) as well as greater drinking days (DD: p < .004), average drinks per drinking day/week (AvgD: p < .001) and relapse to heavy drinking (p < .05), while higher levels of pretreatment AW symptoms interacted with treatment week to predict greater HDD (p < .018). Abstinence symptoms of depression, anxiety, and sleep difficulties were associated with craving and AW but did not predict any drinking-related outcomes.

CONCLUSIONS

These results provide evidence that increased alcohol craving and AW may serve as prognostic indicators of greater risk of heavy drinking in outpatient treatment. Findings suggest the need to evaluate craving and AW at outpatient treatment entry and develop targeted treatments to specifically address the effects of craving and AW on drinking outcomes in outpatient AUD treatment.

Transdermal sensor features correlate with ecological momentary assessment drinking reports and predict alcohol-related consequences in young adults' natural settings

BACKGROUND

Wearable transdermal alcohol concentration (TAC) sensors allow passive monitoring of alcohol concentration in natural settings and measurement of multiple features from drinking episodes, including peak intoxication level, speed of intoxication (absorption rate) and elimination, and duration. These passively collected features extend commonly used self-reported drink counts and may facilitate the prediction of alcohol-related consequences in natural settings, aiding risk stratification and prevention efforts.

METHOD

A total of 222 young adults aged 21-29 (M age = 22.3, 64% female, 79% non-Hispanic white, 84% undergraduates) who regularly drink heavily participated in a 5-day study that included the ecological momentary assessment (EMA) of alcohol consumption (daily morning reports and participant-initiated episodic EMA sequences) and the wearing of TAC sensors (SCRAM-CAM anklets). The analytic sample contained 218 participants and 1274 days (including 554 self-reported drinking days). Five features-area under the curve (AUC), peak TAC, rise rate (rate of absorption), fall rate (rate of elimination), and duration-were extracted from TAC-positive trajectories for each drinking day. Day- and person-level associations of TAC features with drink counts (morning and episodic EMA) and alcohol-related consequences were tested using multilevel modeling.

RESULTS

TAC features were strongly associated with morning drink reports (r = 0.6-0.7) but only moderately associated with episodic EMA drink counts (r = 0.3-0.5) at both day and person levels. Higher peaks, larger AUCs, faster rise rates, and faster fall rates were significantly predictive of day-level alcohol-related consequences after adjusting for both morning and episodic EMA drink counts in separate models. Person means of TAC features added little above daily scores to the prediction of alcohol-related consequences.

CONCLUSIONS

These results support the utility of TAC sensors in studies of alcohol misuse among young adults in natural settings and outline the specific TAC features that contribute to the day-level prediction of alcohol-related consequences. TAC sensors provide a passive option for obtaining valid and unique information predictive of drinking risk in natural settings.

The Clinical Course of Alcohol Use Disorder Depicted by Digital Biomarkers

Aims: This study introduces new digital biomarkers to be used as precise, objective tools to measure and describe the clinical course of patients with alcohol use disorder (AUD).

Methods: An algorithm is outlined for the calculation of a new digital biomarker, the recovery and exacerbation index (REI), which describes the current trend in a patient's clinical course of AUD. A threshold applied to the REI identifies the starting point and the length of an exacerbation event (EE). The disease patterns and periodicity are described by the number, length, and distance between EEs. The algorithms were tested on data from patients from previous clinical trials (n = 51) and clinical practice (n = 1,717).

Results: Our study indicates that the digital biomarker-based description of the clinical course of AUD might be superior to the traditional self-reported relapse/remission concept and conventional biomarkers due to higher data quality (alcohol measured) and time resolution. We found that EEs and the REI introduce distinct tools to identify qualitative and quantitative differences in drinking patterns (drinks per drinking day, phosphatidyl ethanol levels, weekday and holiday patterns) and effect of treatment time.

Conclusions: This study indicates that the disease state—level, trend and periodicity—can be mathematically described and visualized with digital biomarkers, thereby improving knowledge about the clinical course of AUD and enabling clinical decision-making and adaptive care. The algorithms provide a basis for machine-learning-driven research that might also be applied for other disorders where daily data are available from digital health systems.

A new generation of transdermal alcohol biosensing technology: practical applications, machine -learning analytics and questions for future research

The use of transdermal alcohol monitors has burgeoned in recent years, now encompassing hundreds of thousands of individuals globally. A new generation of sensors promises to expand the range of applications for transdermal technology exponentially, and advances in machine-learning modeling approaches offer new methods for translating the data produced by transdermal devices. This article provides (1) a review of transdermal sensor research conducted to date, including an analysis of methodological features of past studies potentially key in driving reported sensor performance; (2) updates on methodological developments likely to be transformative for the field of transdermal sensing, including the development of new-generation sensors featuring smartphone integration and rapid sampling capabilities as well as developments in machine-learning analytics suited to data produced by these novel sensors and; (3) an analysis of the expanded range of applications for this new generation of sensor, together with corresponding requirements for sensor accuracy and temporal specificity. We also note questions as yet unanswered and key directions for future research.

Wrist-worn alcohol biosensors: Applications and usability in behavioral research

Wrist-worn alcohol biosensor technology has developed rapidly in recent years. These devices are light, easy to wear, relatively inexpensive, and resemble commercial fitness trackers. As a result, they may be more suitable for a wide range of clinical and research applications. In this paper, we describe three pilot projects examining the associations between reported drinking behavior and transdermal alcohol concentration (TAC) derived from a new, wrist-worn alcohol biosensor (BACtrack Skyn) in diverse participant groups and settings. Study 1 (N = 3) compared Skyn-derived TAC with that from an ankle-worn alcohol sensor (SCRAM CAM) and breath alcohol concentration (BrAC) in a laboratory setting. Study 2 (N = 10) compared Skyn TAC with BrAC during a naturalistic drinking episode in the field. Study 3 (N = 12) used the Skyn to monitor alcohol use in the field for 2 weeks. Studies 2 and 3 also collected usability and acceptability data from participants. The results of Study 1 showed that the Skyn produced a TAC curve that closely resembled that of the validated SCRAM CAM anklet. In Study 2, Skyn detected drinking for all 10 participants (peak BrAC range: 0.02-0.21) with an average delay of 35.6 ± 10.2 min after the start of self-reported drinking. In Study 3, Skyn reliably recorded continuous TAC data showing multiple drinking episodes over the monitoring period. Participants in Studies 2 and 3 both reported Skyn as highly acceptable. Collectively, the results of these pilot studies show that the Skyn was able to reliably detect drinking events in the laboratory and natural environments. We offer suggestions for further refinements of alcohol biosensors and accompanying analytic software that may facilitate adoption of these devices as cost-effective, user-friendly, and reliable tools to passively and accurately assess alcohol use in the field.

Alcohol subjective responses in heavy drinkers: Measuring acute effects in the natural environment versus the controlled laboratory setting

BACKGROUND

For decades, laboratory alcohol challenges have been the "gold standard" for measuring individual differences in alcohol's subjective effects. However, these approaches are expensive and labor-intensive, making them impractical for large-scale use. This study examined the reliability and validity of a new high-resolution EMA (HR-EMA) ambulatory approach to assessing alcohol use and subjective responses in drinkers' natural environments.

METHODS

Participants were 83 young adult heavy social drinkers (58% male; mean ± SD age = 25.4 ± 2.6 years) who completed up to two smartphone-based, 3-h HR-EMA assessments of alcohol use and related subjective responses in their typical drinking environments. Reported alcohol consumption during the HR-EMA periods was used to calculate estimated blood alcohol concentration (eBAC). Subjective effects were measured using the Brief Biphasic Alcohol Effects Scale (B-BAES) and Drug Effects Questionnaire (DEQ). All participants also completed identical measures during a separate, 4 to 5-h laboratory session in which they received a 0.8 g/kg alcohol challenge.

RESULTS

Most natural environment drinking episodes (87%) met or exceeded the threshold for binge drinking (final mean eBAC = 0.12 g/dl). Associations between reported alcohol use and subjective responses on the B-BAES and DEQ were strongest earlier in the drinking events, with fair reliability of reported subjective effects across two HR-EMA episodes (intraclass correlation [ICC] range = 0.46-0.49). There was fair-to-good correspondence between HR-EMA- and laboratory-derived subjective responses (ICC range = 0.49-0.74), even after accounting for differences in alcohol consumption and drinking context. Reported stimulating and rewarding alcohol effects were higher in the ambulatory than laboratory setting, and vice versa for sedating effects.

CONCLUSIONS

This study supports the reliability and validity of smartphone-based HR-EMA to measure alcohol use and subjective responses in heavy drinkers' natural environments. These findings lend support to the use of ambulatory HR-EMA as a measure of alcohol subjective responses in risky drinkers when a laboratory protocol is not practical, feasible, or safe.

Ecological Momentary Assessment of Alcohol Consumption and Its Concordance with Transdermal Alcohol Detection and Timeline Follow-Back Self-report Among Adults Experiencing Homelessness

Background

Studies of alcohol use presume valid assessment measures. To evaluate this presumption, we examined the concordance of alcohol use as measured by ecological momentary assessment (EMA) self‐reports, transdermal alcohol concentration readings via the Secure Continuous Remote Alcohol Monitor (SCRAM), and retrospective self‐reports via the Timeline Follow‐Back (TLFB) among adults experiencing homelessness.

Methods

Forty‐nine adults who reported alcohol misuse (mean age = 47, SD = 9; 57% Black; 82% men) were recruited from a homeless shelter. For 4 weeks, alcohol use was assessed: (i) 5 times or more per day by EMA, (ii) every 30 minutes by a SCRAM device worn on the ankle, and (iii) by TLFB for the past month at the end of the study period. There were 1,389 days of observations of alcohol use and alcohol use intensity for 49 participants.

Results

EMA and SCRAM alcohol use data agreed on 73% of days, with an interrater agreement Kappa = 0.46. A multilevel analysis of concordance of 3 measures for alcohol use yielded statistically significant correlations of 0.40 (day level) and 0.63 (person level) between EMA and SCRAM. Alcohol use was detected on 49, 38, and 33% of days by EMA, SCRAM, and TLFB, respectively. For alcohol use intensity, EMA and SCRAM resulted in statistically significant correlations of 0.46 (day level) and 0.78 (person level). The concordance of TLFB with either EMA or SCRAM was weak, especially at the day level.

Conclusions

This is the first study to examine concordance of alcohol use estimates using EMA, SCRAM, and TLFB methods in adults experiencing homelessness. EMA is a valid approach to quantifying alcohol use, especially given its relatively low cost, low participant burden, and ease of use. Furthermore, any stigma associated with wearing the SCRAM or reporting alcohol use in person may be attenuated by using EMA, which may be appealing for use in studies of stigmatized and underserved populations.

Shame's Associations with Depression and Problem Drinking: An Ecological Momentary Study

INTRODUCTION

Depression and problem drinking are comorbid in emerging adulthood, yet the processes that link them are not well understood. Research has argued that shame has a unique influence on the experience of problematic drinking, but this has rarely been assessed at the state level. Using ecological momentary assessments (EMAs), we assessed whether shame, and not guilt, mediated the association between baseline depression and alcohol use and problems.

METHODS

One hundred and eighty-four emerging adults (M_age= 19.27) completed a 12-day EMA study. Multilevel models were used to test hypotheses.

RESULTS

In a model with alcohol use as the outcome, there were no significant associations between shame or guilt and alcohol use at the within- or between-subjects level. In a model with alcohol problems as the outcome, guilt was positively associated with alcohol problems but only at the daily level. At the between-subjects level and after controlling for guilt, there was a significant association between depression, shame, and alcohol problems; average levels of shame mediated the association between depression and alcohol problems. In post-hoc reverse directionality models, average alcohol problems mediated the relationship between depression and shame and guilt at the between-person level. No mediation was present for alcohol use.

CONCLUSION

After controlling for guilt, shame is an emotion that helps explain risk for alcohol problems among depressed emerging adults, which has implications for targeted interventions. Reciprocal associations between shame, guilt, and alcohol problems emerged highlighting the need for more fulsome assessments of shame and guilt in future EMA research.

Examining protocol compliance and self-report congruence between daily diaries and event-contingent ecological momentary assessments of college student drinking

BACKGROUND

Daily diaries and ecological momentary assessments (EMA) are frequently used to assess event-level college student drinking. While both methods have advantages, they also raise questions about data validity, particularly in regard to alcohol's impact on protocol compliance. The current study examined congruence in drinking behaviors reported via retrospective daily diaries and event-contingent drinking logs, protocol compliance with each method, and the extent to which alcohol consumption impacted compliance.

METHODS

Participants were first-semester college women (n = 69) who reported 4+ drinks during an occasion at least once in the past month. Participants reported the number of drinks consumed and subjective intoxication using a 14-day EMA protocol. Event-contingent drinking logs (via self-initiated EMA) assessed behavior immediately after each drinking event; daily diaries assessed behaviors from the previous day. Pairwise correlations examined congruence between drinking logs and corresponding daily dairies; protocol compliance was examined through descriptive analysis of data missingness; and multilevel regression models assessed the associations between protocol compliance, alcohol consumption, and subjective intoxication.

RESULTS

Drinking log and daily diary reports were highly correlated (r's = 0.70 to 0.93). On drinking days, diary reports had higher protocol compliance (96.0%) compared to momentary drinking logs (41.4%). Drinking log missingness was associated with greater alcohol use and subjective intoxication reported in the corresponding daily diary (p's < 0.05).

CONCLUSIONS

Similarities in reports of alcohol consumption and subjective intoxication, coupled with higher missingness of momentary assessments suggest daily diaries may have methodological advantages and unique utility in supplementing momentary assessments.

Drinking motives moderate daily-life associations between affect and alcohol use in individuals with borderline personality disorder

People often report drinking to cope with negative affect (NA) or to enhance positive affect (PA). However, findings from daily life studies examining the interaction of motives and affect to predict alcohol use are mixed. Individuals with borderline personality disorder (BPD) may be particularly susceptible to drinking for the purpose of changing affective states, representing a population in which these patterns may be more readily identifiable in daily life. We tested whether drinking motives moderate daily life associations between affect and drinking in individuals with BPD. Regular drinkers with BPD (N = 54; 81.5% female) completed ecological momentary assessments approximately 6-10 times daily for 21 days. We tested whether the interactions between (a) person-level coping motives and NA so far that day (i.e., cumulative-average NA), and (b) person-level enhancement and cumulative-average PA were associated with subsequent drinking. We also tested whether effects differed for the initiation versus continuation of a drinking episode. Using generalized estimating equations, the interaction between coping and cumulative-average NA was positively associated with momentary drinking, with some evidence for a stronger relation during the continuation of drinking. The interaction between enhancement motives and cumulative-average PA was positively associated with initiation but negatively associated with continuation of drinking. Our novel approach of using cumulative-average affect and distinguishing initiation and continuation of drinking allowed us to examine differential momentary patterns across the drinking episode, and results suggest that awareness of motives as well as affect leading up to and during drinking may be a useful intervention target. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Alcohol use in daily life: Examining the role of trait and state impulsivity facets

OBJECTIVES

Using ecological momentary assessment (EMA) methods we aimed to investigate the influence of trait and state (momentary) impulsivity on alcohol use behaviors in daily life. Facets of the UPPS trait model of impulsivity (Whiteside & Lynam, 2001) have been found to differentially relate to alcohol-related outcomes and behaviors in cross-sectional and longitudinal studies. The present work expands on this by assessing UPPS facets in daily life and examining the contributions of trait and state impulsivity facets to daily life drinking behavior.

METHOD

Forty-nine participants were prompted at least 6 times per day for 21 days. A total of 4,548 collected EMA reports were included in analyses. Multilevel models were computed predicting daily life alcohol use behaviors from state and trait impulsivity facets and relevant covariates.

RESULTS

Individual facets of momentary impulsivity differentially related to alcohol outcomes, such that (lack of) premeditation and, to a lesser extent, sensation seeking showed unique patterns of association with drinking and drinking quantity. Only trait levels of (lack of) premeditation were related to drinking behavior in daily life; no other trait UPPS scale significantly related to alcohol use.

CONCLUSIONS

These results highlight state difficulties with premeditation as particularly relevant to drinking behavior in daily life. Our results also support the incremental validity of state impulsivity facets over trait level measures in relation to drinking behavior in daily life. These findings offer important insight into the phenomenology of daily life alcohol use and highlight possible avenues for intervention and prevention efforts. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Translational approach to understanding momentary factors associated with alcohol consumption

Multiple interindividual and intra-individual factors underlie variability in drinking motives, challenging clinical translatability of animal research and limiting treatment success of substance use-related problems. Intra-individual variability refers to time-dependent continuous and discrete changes within the individual and in substance use research is studied as momentary variation in the internal states (craving, stressed, anxious, impulsive and tired) and response to external triggers (stressors, drug-associated environmental cues and social encounters). These momentary stimuli have a direct impact on behavioural decisions and may be triggers and predictors of substance consumption. They also present potential targets for real-time behavioural and pharmacological interventions. In this review, we provide an overview of the studies demonstrating different momentary risk factors associated with increased probability of alcohol drinking in humans and changes in alcohol seeking and consumption in animals. The review also provides an overview of pharmacological interventions related to every individual risk factor.

Annual Research Review: Ecological momentary assessment studies in child psychology and psychiatry

BACKGROUND

Enhancements in mobile phone technology allow the study of children and adolescents' everyday lives like never before. Ecological momentary assessment (EMA) uses these advancements to allow in-depth measurements of links between context, behavior, and physiology in youths' everyday lives.

FINDINGS

A large and diverse literature now exists on using EMA to study mental and behavioral health among youth. Modern EMA methods are built on a rich tradition of idiographic inquiry focused on the intensive study of individuals. Studies of child and adolescent mental and behavioral health have used EMA to characterize lived experience, document naturalistic within-person processes and individual differences in these processes, measure familiar constructs in novel ways, and examine temporal order and dynamics in youths' everyday lives.

CONCLUSIONS

Ecological momentary assessment is feasible and reliable for studying the daily lives of youth. EMA can inform the development and augmentation of traditional and momentary intervention. Continued research and technological development in mobile intervention design and implementation, EMA-sensor integration, and complex real-time data analysis are needed to realize the potential of just-in-time adaptive intervention, which may allow researchers to reach high-risk youth with intervention content when and where it is needed most.

An examination of the extent to which mood and context are associated with real-time alcohol consumption

AIM

To assess the effects of mood, social and environmental contexts and alcohol-related beliefs on alcohol consumption.

METHOD

Participants (N = 69) recorded their positive and negative outcome expectancies and self-reported mood prior to drinking (Time 1 mood). A Smartphone App then enabled alcohol consumption (total number of drinks aggregated from reports throughout a drinking occasion, current mood (Time 2 mood), social context e.g., with friends and environmental location e.g., in a bar/pub to be documented in de facto real-time a total of 3009 data points.

RESULTS

Feeling unhappy prior to consumption onset was associated with a significant increase in drinking. During a drinking occasion, feeling happy was a significant predictor of drinking larger quantities. Interestingly, however, an interaction between T1 and T2 mood suggested it is not mood prior to consumption which drives drinking, but rather that alcohol consumption elevates mood. Being with two or more friends (relative to being alone) also predicted increased consumption. Positive and negative expectancies were not found to be significant predictors within these models.

CONCLUSION

By showing that both mood and social context may shape alcohol behaviors distinctly, the current study suggests that alcohol research and intervention efforts may benefit from greater consideration of the temporally-mediated contextual influences on alcohol consumption.

Alcohol Consumption, Drinking Patterns, and Cognitive Performance in Young Adults: A Cross-Sectional and Longitudinal Analysis

Long-term alcohol abuse is associated with poorer cognitive performance. However, the associations between light and moderate drinking and cognitive performance are less clear. We assessed this association via cross-sectional and longitudinal analyses in a sample of 702 Dutch students. At baseline, alcohol consumption was assessed using questionnaires and ecological momentary assessment (EMA) across four weeks (‘Wave 1’). Subsequently, cognitive performance, including memory, planning, and reasoning, was assessed at home using six standard cognition tests presented through an online platform. A year later, 436 students completed the four weeks of EMA and online cognitive testing (‘Wave 2’). In both waves, there was no association between alcohol consumption and cognitive performance. Further, alcohol consumption during Wave 1 was not related to cognitive performance at Wave 2. In addition, EMA-data-based drinking patterns, which varied widely between persons but were relatively consistent over time within persons, were also not associated with cognitive performance. Post-hoc analyses of cognitive performance revealed higher within-person variance scores (from Wave 1 to Wave 2) than between-person variance scores (both Wave 1 and Wave 2). In conclusion, no association was observed between alcohol consumption and cognitive performance in a large Dutch student sample. However, the online cognitive tests performed at home may not have been sensitive enough to pick up differences in cognitive performance associated with alcohol consumption.

Ecological momentary assessment studies of comorbid PTSD and alcohol use: A narrative review

INTRODUCTION

PTSD and harmful alcohol use, including alcohol use disorder (AUD), frequently co-occur. Recent research has used ecological momentary assessment (EMA) to examine the associations between PTSD symptoms and alcohol-related variables, such as craving for alcohol, alcohol use, and the presence of alcohol-related problems. The overall purpose of this narrative review is to summarize this emerging literature.

METHODS

Inclusion criteria for studies were: 1) Use of ecological momentary assessment as the method for gathering data on alcohol use and/or craving in populations with both problematic alcohol use and PTSD, and the inclusion of an assessment of both PTSD symptoms and at least one alcohol use variable during EMA; and 2) At screening, participants were required to meet study criteria for a) elevated PTSD symptoms or trauma exposure, and b) alcohol use.

RESULTS

The pertinent extant literature is reviewed in terms of four underlying themes: Methodological considerations of EMA research in a population with PTSD symptoms and harmful alcohol use; Associations between PTSD symptoms and alcohol use variable/s; Moderators of PTSD-alcohol use associations; Mediators of PTSD-alcohol use associations.

CONCLUSIONS

Collectively, studies provide support for the self-medication hypothesis. Several variables were found to moderate association between PTSD symptoms and alcohol-related variables. EMA data may ultimately be useful in identifying when individuals are at risk for harm due to increased symptoms or alcohol misuse and may inform treatment approaches administered remotely.

Real-Time Mobile Monitoring of Drinking Episodes in Young Adult Heavy Drinkers: Development and Comparative Survey Study

Background

Binge drinking, defined as consuming five or more standard alcoholic drinks for men (four for women) within a 2-hour period, is common among young adults and is associated with significant alcohol-related morbidity and mortality. To date, most research on this problem in young adults has relied upon retrospective questionnaires or costly laboratory-based procedures. Smartphone-based ecological momentary assessment (EMA) may address these limitations by allowing researchers to measure alcohol use and related consequences in real time and in drinkers’ natural environments. To date, however, relatively less research has systematically examined the utility of this approach in a sample of young adults targeting real-world heavy drinking episodes specifically.

Objective

This study aimed to evaluate the feasibility, acceptability, and safety of a smartphone-based EMA method targeting binge drinking and related outcomes in heavy drinking young adults during real-world drinking occasions.

Methods

Young adult binge drinkers in the smartphone group (N=83; mean 25.4 (SD 2.6) years; 58% (48/83) male; bingeing on 23.2% (6.5/28) days in the past month) completed baseline measures of alcohol use and drinking-related consequences, followed by up to two smartphone-based EMA sessions of typical drinking behavior and related outcomes in their natural environments. They also completed next-day and two-week follow-up surveys further assessing alcohol use and related consequences during the EMA sessions and two weeks after study participation, respectively. A separate demographic- and drinking-matched safety comparison group (N=25) completed the baseline and two-week follow-up surveys but did not complete EMA of real-world drinking behavior.

Results

Most participants (71%, 59/83) in the smartphone group engaged in binge drinking during at least one 3-hour EMA session, consuming 7.3 (SD 3.0) standard alcoholic drinks. They completed 87.2% (507/581) system-initiated EMA prompts during the real-world drinking episode, supporting the feasibility of this approach. The procedure was acceptable, as evidenced by high participant ratings for overall satisfaction with the EMA software and study procedures and low ratings for intrusiveness of the mobile surveys. Regarding safety, participants endorsed few drinking-related consequences during or after the real-world drinking episode, with no adverse or serious adverse events reported. There were no differences between the groups in terms of changes in drinking behavior or consequences from baseline to two-week follow-up.

Conclusions

This study provided preliminary support for the feasibility, acceptability, and safety of a smartphone-based EMA of real-time alcohol use and related outcomes in young adult heavy drinkers. The results suggest that young adults can use smartphones to safely monitor drinking even during very heavy drinking episodes. Smartphone-based EMA has strong potential to inform future research on the epidemiology of and intervention for alcohol use disorder by providing researchers with an efficient and inexpensive way to capture large amounts of data on real-world drinking behavior and consequences.

Comparing Alcohol Use Disorders Identification Test (AUDIT) with Timeline Follow Back (TLFB), DSM-5 and Phosphatidylethanol (PEth) for the assessment of alcohol misuse among young people in Ugandan fishing communities

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Validated tools are needed to evaluate alcohol-reduction interventions in low income countries.

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Among young Ugandans ACASI-administered 30-day and 12-month-AUDIT have good diagnostic properties.

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Self-reported AUDIT provides an efficient means of assessing alcohol misuse.

Background

Validated tools for assessing alcohol use among young people in low-income countries are needed to estimate prevalence and evaluate alcohol-reduction interventions. We validated Alcohol Use Disorders Identification Test (AUDIT) against Timeline Follow Back (TLFB), Diagnostic and Statistical Manual of Mental Disorders (DSM-5) and phosphatidylethanol (PEth); and the 30-day-AUDIT against the 12-months-AUDIT among young Ugandans.

Methods

In 2018, we collected retrospective data on 30-day and 12-month AUDIT, TLFB and DSM-5 in a cross-sectional study of 15–24 year old residents of Ugandan fishing communities. AUDIT was administered by Audio Computer Assisted Self-Interviewing (ACASI) and DSM-5 and TLFB by psychiatric nurses. We determined PEth16:0/18:1 levels from dried blood spots using liquid chromatography tandem-mass spectrometry (heavy usage, ≥210 ng/mL) and calculated sensitivity and specificity of AUDIT against the other measures.

Results

Among 1281 participants (52.7% male, mean age 20 years), half (n = 659; 51.4%) reported ever drinking alcohol, 19.4% had 12-month-AUDIT ≥ 8 (21.5% men; 17.0% women), and 24.2% had 30-day-AUDIT ≥ 8 (29.0% men; 18.9% women). Twenty percent of participants had detectable PEth with 55 (4.3%) classified as heavy drinkers; 50.7% reported ≥ 2 symptoms on DSM-5 and 6.3% reported binge drinking in the previous month based on TLFB (8.9% men, 3.5% women). The 30-day-AUDIT ≥ 8 had sensitivity 86.7%, 95%CI: 81.8%–90.7% and specificity 90.9%, 95%CI:89.0%–92.6% versus 12-month-AUDIT ≥ 8. Both 30-day and 12-month-AUDIT ≥ 8 were sensitive and specific markers of heavy drinking by PEth (12-month-AUDIT sensitivity = 80.0%; 95%CI:67.0%–89.6%; specificity = 83.3%; 95%CI:81.1%–85.3%). The 30-day-AUDIT was a sensitive and specific marker of binge drinking based on TLFB (sensitivity = 82.7%; 95%CI:72.7%–90.2%, specificity = 79.8%; 95%CI:77.4%–82.1%); 12-month-AUDIT had lower sensitivity. Both 30-day and 12-month AUDIT ≥ 8 were highly specific but insensitive markers of having DSM-5 ≥ 2 symptoms.

Conclusion

Among young people in Uganda, ACASI-administered 30-day and 12-month-AUDIT have good diagnostic properties compared to PEth, DSM-5 and TLFB. Self-reported AUDIT provides a quick and valid means of assessing alcohol misuse in these communities.

Item Responses in Quantity-Frequency Questionnaires: Implications for Data Generalizability

Alcohol consumption is an important predictor of a variety of negative outcomes. There is an extensive literature that examines the differences in the estimated level of alcohol consumption between types of assessments (e.g., quantity-frequency [QF] questionnaires, daily diaries). However, it is typically assumed that all QF-based measures are nearly identical in their assessment of the volume of alcohol consumption in a population. Using timeline follow-back data and constructing common QF consumption measures, we examined differences among survey instruments to assess alcohol consumption and heavy drinking. Using three data sets, including clinical to community samples, we demonstrate how scale-specific item characteristics (i.e., number of response options and ranges of consumption assessed by each option) can substantially affect the estimated mean level of consumption and estimated prevalence of binge drinking. Our analyses suggest that problems can be mitigated by employing more resolved measures of quantity and frequency in consumption questionnaires.

Wearable Enzymatic Alcohol Biosensor

Transdermal alcohol biosensors have the ability to detect the alcohol that emanates from the bloodstream and diffuses through the skin. However, previous biosensors have suffered from long-term fouling of the sensor element and drift in the resulting sensor readings over time. Here, we report a wearable alcohol sensor platform that solves the problem of sensor fouling by enabling drift-free signals in vivo for up to 24 h and an interchangeable cartridge connection that enables consecutive days of measurement. We demonstrate how alcohol oxidase enzyme and Prussian Blue can be combined to prevent baseline drift above 25 nA, enabling sensitive detection of transdermal alcohol. Laboratory characterization of the enzymatic alcohol sensor demonstrates that the sensor is mass-transfer-limited by a diffusion-limiting membrane of lower permeability than human skin and a linear sensor range between 0 mM and 50 mM. Further, we show continuous transdermal alcohol data recorded with a human subject for two consecutive days. The non-invasive sensor presented here is an objective alternative to the self-reports used commonly to quantify alcohol consumption in research studies.