Accuracy of Wearable Transdermal Alcohol Sensors: Systematic Review

Use of Wearable Transdermal Alcohol Sensors for Monitoring Alcohol Consumption After Detoxification With Contingency Management: Pilot Randomized Feasibility Trial

BACKGROUND

Wearable transdermal alcohol sensor (TAS) devices generate continuous data on alcohol consumption through the indiscernible sweat vapors on the skin. This continuous alcohol monitoring capability could provide a new method for alcohol services to monitor service users at various stages of their alcohol treatment.

OBJECTIVE

We aimed to assess the feasibility of using a TAS as part of alcohol treatment with alcohol service users using the device with or without contingency management (CM).

METHODS

A feasibility study was conducted of a convenience sample of 29 current service users from 3 South London alcohol services. Participants were randomized into either a control (treatment as usual) or CM group (treatment as usual+CM). We assessed the feasibility of enrollment, participation, device tampering and return, and device wearability and the accuracy of data capture. These data were reported descriptively where appropriate, the groups were compared, and alcohol self-report data were compared to the transdermal alcohol concentration to assess accuracy.

RESULTS

A total of 34 individuals were approached, and 32 (94%) were enrolled and randomized (n=17, 53% to the control group and n=15, 47% to the CM group) over 5 months. In total, 3 participants withdrew (n=2, 67% from the control group and n=1, 33% from the CM group). There was a total of 203 meetings arranged (29 participants × 7 meetings), and 185 (91.1%) were attended. Only 1 of the 29 participants (3%) admitted to turning the TAS off to avoid monitoring. There were some issues with the TAS not functioning properly and not being able to be cleaned. Removals were recorded, but the definition of TAS removal may need to be improved for future trials. There was a high TAS return rate (28/29, 97% of the participants returned the TAS). Secondary outcomes suggest that the BACtrack Skyn remains an accurate tool to monitor alcohol consumption compared to self-report data and that it is acceptable to wearers over 2 weeks, with many participants (27/28, 96%) answering that they would wear it again and for longer but that the CM procedure could be made clearer.

CONCLUSIONS

The delivery of CM via a TAS was feasible in this study, but recommendations for a future larger trial include that the study design should be changed to provide an operationalized rather than manual method of checking whether TAS data meet CM criteria. This would reduce researcher burden and researcher and participant time. Current recruitment and research meeting design seem suitable for a future larger trial.

TRIAL REGISTRATION

International Standard Randomised Controlled Trial Number (ISRCTN) ISRCTN46845361; https://www.isrctn.com/ISRCTN46845361.

Cheers to tomorrow? Alcohol use predicts poorer mood and well-being the next day in young adults

Alcohol use is embedded within university culture. While the consequences of alcohol use on next-day physical health are well-known, less is known about the consequences to next-day emotional health. This study investigated the relationship between alcohol use and next-day mood and well-being using two daily diary studies with New Zealand university students. Participants completed a daily diary for 13 days (Study 1, n = 1114; 30.6% men, Mage = 19.6) or 7 days (Study 2, n = 212; 24.5% men, Mage = 19.4) where they reported previous night's alcohol consumption and sleep quality, along with today's mood and well-being. Night-time alcohol consumption was categorised into low-risk (women 1-4 drinks, men 1-5 drinks), medium-risk (women 5-9 drinks, men 6-11 drinks) and high-risk (women 10+ drinks, men 12+ drinks) according to New Zealand public health guidelines. Across both studies, medium- and especially high-risk drinking, but not low-risk drinking, was associated with lower next-day positive mood and well-being compared to nondrinking days. Poorer sleep quality partially accounted for the relationship of drinking with next-day mood and well-being in Study 1, but less so in Study 2. Findings suggest that interventions could promote lower risk drinking behaviours to benefit students' well-being.

Systematic review on resting-state fMRI in people with AUD and people who binge drink

Resting-state functional magnetic resonance imaging (rsfMRI) has become ubiquitous in neuroimaging to study disorders, including alcohol use disorder (AUD), given its potential to serve as a biomarker of psychiatric symptoms. The number of techniques, sample heterogeneity, and findings demand the assessment of results to identify potential biomarkers for the development of treatment. This systematic review aimed to synthesize the alcohol rsfMRI literature by summarizing the results by analysis approach and groups to examine these findings in the context of the neurobiology of addiction model. Three databases were systematically searched, resulting in the inclusion of 17 studies with a total of 784 participants (387 were people with AUD, 38 engaged in binge drinking, and 359 were controls). Seed-based functional connectivity studies were the most prominent. Compared to controls, people who binge drink and people with AUD showed greater connectivity of the Middle Frontal Gyrus-a region associated with the preoccupation/anticipation stage of the theory. Regions of the prefrontal and limbic cortex were most consistently reported in studies. The different types of analyses, sample size, and variability in the sample may have contributed to differences reported across studies. This review synthesizes and examines the results of different studies using the neurobiology of addiction theory, which may inform future studies on potential regions of interest, recruitment approaches, and analysis methods. Standardizing the methods for such a heterogeneous population could lead to more rapid development of neurobiologically-informed treatments for AUD.

What hepatology clinicians and their patients with alcohol-related liver disease think of wearable alcohol biosensors to aid abstinence from alcohol: A qualitative study

INTRODUCTION

We aimed to determine acceptability and feasibility of innovative wearable alcohol biosensor monitors (ABM) for patients with alcohol-related liver disease (ALD) and their clinicians.

METHODS

Patients and clinicians at a tertiary care centre participated in qualitative interviews on usability, acceptability, feasibility, efficiency/effectiveness, impact of device on behaviour/clinical practice and preferences/barriers. Interviews were audiotaped, transcribed and coded using a constant comparison method for category themes.

RESULTS

Patients (n = 23) were 56% female, mean 44 years old, 87% White, with moderate-severe liver disease. Some felt the ABMs appearance was unappealing; others felt it provided an opportunity for openness and education of others. While some found it feasible to wear, others felt it was unrealistic to wear 24/7. Importantly, there were many positive themes on effectiveness/efficiency-participants felt the ABM could better record their alcohol use and patterns of use than they could remember. Patients felt wearing the ABM motivated abstinence, gave accountability and was a source of security. Clinicians (n = 13) were mostly hepatologists (77%), seeing on average 38 ALD patients/month. Clinicians felt seeing patterns and amounts of alcohol use could inform clinical decision making and treatments but expressed concern over the volume and complexity of data.

DISCUSSION AND CONCLUSIONS

Perspectives on ABMs for managing ALD were mixed among patients and providers. Future device designs may overcome acceptability barriers due to device appearance. However, for clinicians, the logistics of data gathering plus the complexity and volume of data produced by the ABM device requires considerable thought to make this an efficient tool for clinical use.

CLINICALTRIALS

gov identifier NCT03533660: Alcohol biosensor monitoring for alcohol liver disease.

Impact of Acute Alcohol Consumption on Sexuality: A Look at Psychological Mechanisms

Alcohol's link with sexuality is long-standing and prominent. While research continues to document robust associations between drinking and sexual behavior, scientific attention now centers primarily on evaluating mechanisms and attendant theoretical frameworks to advance our understanding of how alcohol exerts a causal impact. We describe four domains with reliable evidence of alcohol effects: sexualized social perceptions, sexual arousal, sexual risk taking, and sexual assault. We consider three contextual frames: distal factors associated with encountering opportunities for alcohol-involved sex, proximal factors associated with alcohol's acute effects, and distal-proximal interactions. We then examine the empirical support for mechanisms embedded within four theoretical frameworks: alcohol disinhibition, alcohol expectancy, alcohol myopia, and emotion regulation. Support for disinhibition mechanisms is evident with sexual arousal only. Expectancy and myopia mechanisms enjoy support across domains and make up bases for integrative expectancy-myopia causal explanations. Emotion regulation mechanisms evidence preliminary support in risk taking and sexual assault. Implications and future directions are considered.

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.

Wearable Alcohol Monitoring Device for the Data-Driven Transcutaneous Alcohol Diffusion Model

Wearable alcohol monitoring devices demand noninvasive, real-time measurement of blood alcohol content (BAC) reliably and continuously. A few commercial devices are available to determine BAC noninvasively by detecting transcutaneous diffused alcohol. However, they suffer from a lack of accuracy and reliability in the determination of BAC in real time due to the complex scenario of the human skin for transcutaneous alcohol diffusion and numerous factors (e.g., skin thickness, kinetics of alcohol, body weight, age, sex, metabolism rate, etc.). In this work, a transcutaneous alcohol diffusion model has been developed from real-time captured data from human wrists to better understand the kinetics of diffused alcohol from blood to different skin epidermis layers. Such a model will be a footprint to determine a base computational model in larger studies. Eight anonymous volunteers participated in this pilot study. A laboratory-built wearable blood alcohol content (BAC) monitoring device collected all the data to develop this diffusion model. The proton exchange membrane fuel cell (PEMFC) sensor was fabricated and integrated with an nRF51822 microcontroller, LMP91000 miniaturized potentiostat, 2.4 GHz transceiver supporting Bluetooth low energy (BLE), and all the necessary electronic components to build this wearable BAC monitoring device. The %BAC data in real time were collected using this device from these volunteers' wrists and stored in the end device (e.g., smartphone). From the captured data, we demonstrate how the volatile alcohol concentration on the skin varies over time by comparing the alcohol concentration in the initial stage (= 10 min) and later time (= 100 min). We also compare the experimental results with the outputs of three different input profiles: piecewise linear, exponential linear, and Hoerl, to optimize the developed diffusion model. Our results demonstrate that the exponential linear function best fits the experimental data compared to the piecewise linear and Hoerl functions. Moreover, we have studied the impact of skin epidermis thickness within ±20% and demonstrate that a 20% decrease in this thickness results in faster dynamics compared to thicker skin. The model clearly shows how the diffusion front changes within a skin epidermis layer with time. We further verified that 60 min was roughly the time to reach the maximum concentration, Cmax, in the stratum corneum from the transient analysis. Lastly, we found that a more significant time difference between BACmax and Cmax was due to greater alcohol consumption for a fixed absorption time.

A qualitative exploration of the experiences of transdermal alcohol sensor devices amongst people in receipt of treatment for alcohol use disorder

Introduction

Transdermal alcohol sensors (TAS) have the potential to be used as a clinical tool in alcohol treatment, but there is limited research with individuals with alcohol dependence using TAS. Our study is a qualitative evaluation of the views of people attending alcohol treatment and their experiences of wearing the BACtrack Skyn, within alcohol services in South London.

Methods

Participants with alcohol dependence wore a BACtrack Skyn TAS for one week and met with the researcher every two days, for a total of four meetings (for example: Monday, Wednesday, Friday, and Monday). In the final meeting, a post-wear survey (on their physical, social and comfort experience of the TAS) and semi-structured interview were completed. The Technology Acceptance Model (TAM) informed the topic guide and data analysis.

Results

Adults (N = 16) receiving alcohol treatment were recruited. Three core topics guided analysis: perceived usefulness, perceived ease of use and attitudes towards use. Participants found the TAS easy to wear and felt positive about its appearance and comfort. The only challenges reported were side effects, mostly skin irritation. The main two perceived uses were 1) TAS working as a drinking deterrent and 2) reducing daily breathalyser visits during detox.

Conclusion

Findings support the use of TAS amongst alcohol service users. Wearing the TAS for one week was acceptable and feasible for objective alcohol concentration measurement. Participants reported high perceived ease of use and usefulness of the Skyn in the context of alcohol treatment. These results are encouraging for the use of TAS in clinical settings.

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).

Comparison of transdermal alcohol concentration and self-reported alcohol consumption in people with alcohol dependence attending community alcohol treatment services

AIM

We aimed to assess the accuracy and wearability of a transdermal alcohol sensor (TAS) (BACtrack Skyn) with people currently receiving treatment at alcohol services.

METHOD

A mixed methods observational study involving three NHS alcohol services in south London was conducted. All participants (7=male, 9=female) wore a TAS for 1 week and met with the researcher every other weekday to complete the TAS data download and a TimeLine Follow Back (TLFB). At the end of the week, a post-wear survey was completed. Transdermal Alcohol Concentration (TAC) from the TAS was compared to the TLFB. Post-wear survey responses, attendance voucher incentives and descriptive TAS data (removals, missing and skin temperature data) were analysed. We investigated different drinking event thresholds changing the criteria of TAC level and length of time TAC was increased and analysed each drinking threshold sensitivity, specificity, positive and negative predicative values, and percentage accuracy classification.

RESULTS

The TAS recorded the number of alcohol-drinking days with a high degree of accuracy compared to the TLFB as gold-standard. However, of the participation time of the 16 participants, 14.5% of the TAS data was missing in output and 16.4% of the recorded data suggests the TAS was not currently being worn. Of the data recorded, in line with the drinking event threshold of >15 ug/l TAC, >15minutes, we found that sensitivity = 93%, specificity = 84% and a Pearson correlation of r(16) =.926, p = <.001, BCa 95% CI [.855 -.981]. The threshold with the highest accuracy was TAC>15 ug/l, >60minutes which classified alcohol events with 90% accuracy, AUC =.910, sensitivity = 90%, specificity = 96%. The post-wear survey reported that most participants found it comfortable and that wearing it did not interfere with daily activities. Six participants reported side effects, including itching and a rash, but these would not deter them from wearing it again with all six reporting they would wear the TAS again and for longer than one week.

CONCLUSIONS

The TAS did not capture every drinking event that was self-reported but maintained a high correlation. There were instances of missing TAS data and TAS removals. Overall, our findings would support the acceptability and feasibility of TAS as a tool that could be used in clinical settings for objective alcohol monitoring with patients being responsible for the TAS.

Accuracy of transdermal alcohol monitoring devices in a laboratory setting

The development of transdermal alcohol sensors (TASs) presents a new method to monitor alcohol consumption with the ability to objectively measure data 24/7. We aimed to evaluate the accuracy of two TASs (BACtrack Skyn and Smart Start BARE) in a laboratory setting. Thirty-two adults received a dose of ethanol 0.56 g/kg body weight as a 20% solution while wearing the two TASs and provided Breath Alcohol Concentration (BrAC) measurements for 3.5 h postalcohol consumption. Pearson's correlations and repeated measures analysis of variance tests were conducted on the peak, time-to-peak, and area under the curve data. Bland-Altman plots were derived. A time series analysis and cross-correlations were conducted to adjust for time lag. Both TASs were able to detect alcohol and increase within 20 min. BrAC peaked significantly quicker than Skyn and BARE. BrAC and Skyn peaks were negatively significantly correlated (r = -0.381, P = .035, n = 31), while Skyn and BARE peaks were positively significantly correlated (r = 0.380, P = .038, n = 30). Repeated measures analysis of variance found a significant difference between BrAC, Skyn, and BARE (F(1.946, 852.301) = 459.873, P < .001)). A time series analysis found when BrAC-Skyn and BrAC-BARE were adjusted for the delay to peak, and there was still a significant difference. Failure rates: 1.7% (Skyn) and 4.8% (BARE). Some evidence was obtained for TAS validity as both consistently detected alcohol. Failure rates and time lag show improvements in older device generations. However, neither TAS presented strong equivalence to the breathalyser even when the lag time was adjusted. With further testing and technology advancements, TAS could be a potential alcohol monitoring tool. Two of the newest TAS devices were worn in laboratory conditions for one afternoon to compare their accuracy of alcohol monitoring to a breathalyser. Findings suggest that the two TASs (BACtrack Skyn and SmartStart BARE) recorded significantly similar data postalcohol consumption, but not with the breathalyser.

Phosphatidylethanol vs Transdermal Alcohol Monitoring for Detecting Alcohol Consumption Among Adults

Importance

Alcohol biomarkers can improve detection of heavy alcohol use in clinical care, yet cutoffs for phosphatidylethanol (PEth), a blood biomarker, have not been established.

Objective

To determine the optimal cutoff for PEth for heavy alcohol consumption in a study of middle-age and older adults.

Design, Setting, and Participants

This was a 4-week diagnostic study of adults with paroxysmal atrial fibrillation (AF) and current alcohol consumption, recruited from general cardiology and cardiac electrophysiology outpatient clinics from September 2014 to September 2019. Data were analyzed from October 2021 to March 2022.

Main Outcomes and Measures

The main aim was to determine the optimal PEth cutoff for heavy alcohol consumption, using the Secure Continuous Remote Alcohol Monitor (SCRAM) to measure transdermal alcohol. Area under the curve (AUC) for PEth-detected compared with SCRAM-detected heavy alcohol consumption in any week over the prior 4 weeks (ie, ≥3 [women] and ≥4 [men] episodes) or any estimated breath alcohol of 0.08% or greater in any week, and the PEth cutoff was calculated using the Youden J statistic. Similar analyses were conducted comparing PEth with individual drinks reported by pressing an event monitor, retrospective self-report via the Alcohol Use Disorders Identification Test-Consumption (AUDIT-C), and using 2-week look-backs.

Results

In this diagnostic study of 64 patients with both PEth and SCRAM measures over 4 weeks (54 [84.4%] men; mean age, 65.5 [95% CI, 62.6-68.5] years; 51 [79.7%] White), 31 (48.4%) had any SCRAM-detected heavy alcohol consumption over the 4 weeks, and the median (IQR) PEth at 4 weeks was 23 ng/mL (

Conclusions and Relevance

In a predominately middle-age and older White male population, PEth compared well with SCRAM. A PEth cutoff of 18.5 ng/mL (or rounded to 20 ng/mL, a recommended PEth cutoff for significant alcohol consumption) can be used in clinical care to detect heavy alcohol consumption in middle-age and older men.

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MESH Headings

• Middle Aged
• Humans
• Female
• Male
• Aged
• Alcoholism/diagnosis
• Alcoholism/epidemiology
• Retrospective Studies
• Ethanol
• Alcohol Drinking/epidemiology

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Grants

• K24 AA022586 NIAAA NIH HHS
• R01 AA022222 NIAAA NIH HHS

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Affiliation(s)

Judith A. Hahn Department of Medicine, University of California, San Francisco
Robin Fatch Department of Medicine, University of California, San Francisco
Nancy P. Barnett Department of Behavioral and Social Sciences and the Center for Alcohol and Addiction Studies, Brown University, Providence, Rhode Island
Gregory M. Marcus Department of Medicine, University of California, San Francisco

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Collaborators Collapse

Acceptability and anklet user experience with the SCRAM-CAM transdermal alcohol concentration sensor in regularly drinking young adults' natural environments

Recent developments in wearable technologies have allowed for device-based capture of alcohol concentration among participants in their natural environments. Currently, the Continuous Alcohol Monitor from SCRAM systems (SCRAM-CAM) is the most extensively studied and validated transdermal alcohol concentration (TAC) sensor. However, there has been relatively little work focusing on its acceptability from the participants' perspective. In the current study, we assess the user experience of the SCRAM-CAM anklet in a sample of 222 regularly heavy drinking young adults (mean age = 22.3) who wore the anklet in their natural environments for five 24-h periods spanning 6 consecutive days. Differences in the anklet user experience were measured along a number of dimensions, and differences were tested by sex at birth, white/non-white racial/ethnic group membership, and alcohol use disorder (AUD) risk (measured through Alcohol Use Disorder Identification Test [AUDIT] scores). Males and females differed significantly on six of the eight acceptability items, with males showing more positive responses toward the anklet than females. No differences were found by white/non-white racial/ethnic groups nor AUD risk. Results suggest positive levels of acceptability toward the device overall while in natural environments, further validating the usage of the device in studies that measure alcohol consumption among different groups, including those with high levels of alcohol consumption. Researchers should take into consideration the different levels of burden or discomfort in male versus female participants when using the device.

Use of the BACtrack Skyn alcohol biosensor: Practical applications for data collection and analysis

AIMS

Alcohol biosensors, including the BACtrack Skyn, provide an objective and passive method of continuously assessing alcohol consumption in the natural environment. Despite the many strengths of the Skyn, six key challenges in the collection and processing of data include (1) identifying consumed alcohol; (2) identifying environmental alcohol; (3) identifying and determining the source of missing or invalid data; (4) achieving high participant adherence; (5) integrating Skyn and self-report data; and (6) implications for statistical inference. In this report we outline these challenges, provide recommendations to address them and identify future needs.

DESIGN AND SETTINGS

Procedures from several laboratory and field-based pilot studies are presented to demonstrate practical recommendations for Skyn use. Data from a pilot study including a 7-day ecological momentary assessment period are also presented to evaluate effects of environmental alcohol on BACtrack Skyn readings.

CONCLUSIONS

To address challenges in the collection and processing of data from the BACtrack Skyn alcohol biosensor, researchers should identify goals in advance of data collection to anticipate the processing necessary to interpret Skyn data. The Transdermal Alcohol Sensor Data Macro (TASMAC) version 2.0 software can help to process data rapidly; identify drinking events, missing data and environmental alcohol; and integrate the sensor with self-report data. Thorough participant orientation and regular contact in field studies can reduce missing data and enhance adherence. Many recommended methods for Skyn use are applicable to other alcohol sensors and wearable devices.

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.

Acceptability, Adaptability, and Feasibility of a Novel Computer-Based Virtual Counselor-Delivered Alcohol Intervention: Focus Group and In-depth Interview Study Among Adults With HIV or Tuberculosis in Indian Clinical Settings

BACKGROUND

Unhealthy alcohol use is associated with increased morbidity and mortality among persons with HIV and tuberculosis (TB). Computer-based interventions (CBIs) can reduce unhealthy alcohol use, are scalable, and may improve outcomes among patients with HIV or TB.

OBJECTIVE

We assessed the acceptability, adaptability, and feasibility of a novel CBI for alcohol reduction in HIV and TB clinical settings in Pune, India.

METHODS

We conducted 10 in-depth interviews with persons with alcohol use disorder (AUD): TB (6/10), HIV (2/10), or HIV-TB co-infected (1/10) selected using convenience sampling method, no HIV or TB disease (1/10), 1 focus group with members of Alcoholics Anonymous (AA; n=12), and 2 focus groups with health care providers (HCPs) from a tertiary care hospital (n=22). All participants reviewed and provided feedback on a CBI for AUD delivered by a 3D virtual counselor. Qualitative data were analyzed using structured framework analysis.

RESULTS

The majority (9/10) of in-depth interview respondents were male, with median age 42 (IQR 38-45) years. AA focus group participants were all male (12/12), and HCP focus group participants were predominantly female (n=15). Feedback was organized into 3 domains: (1) virtual counselor acceptability, (2) intervention adaptability, and (3) feasibility of the CBI intervention in clinic settings. Overall, in-depth interview participants found the virtual counselor to be acceptable and felt comfortable honestly answering alcohol-related questions. All focus group participants preferred a human virtual counselor to an animal virtual counselor so as to potentially increase CBI engagement. Additionally, interaction with a live human counselor would further enhance the program's effectiveness by providing more flexible interaction. HCP focus group participants noted the importance of adding information on the effects of alcohol on HIV and TB outcomes because patients were not viewed as appreciating these linkages. For local adaptation, more information on types of alcoholic drinks, additional drinking triggers, motivators, and activities to substitute for drinking alcohol were suggested by all focus group participants. Intervention duration (about 20 minutes) and pace were deemed appropriate. HCPs reported that the CBI provides systematic, standardized counseling. All focus group and in-depth interview participants reported that the CBI could be implemented in Indian clinical settings with assistance from HIV or TB program staff.

CONCLUSIONS

With cultural tailoring to patients with HIV and TB in Indian clinical care settings, a virtual counselor-delivered alcohol intervention is acceptable and appears feasible to implement, particularly if coupled with person-delivered counseling.