Abstract
Abstaining from substance use is a goal of many people with alcohol use disorder (AUD). Understanding patient perspectives of a period of abstinence may assist persons with AUD in achieving this goal. We accessed the electronic health records of adults with AUD entering an emergency department in Baltimore, Maryland, who received a brief peer support intervention for substance use. Data contained open-ended text entered by staff after a patient indicated ever having a sustained period of substance abstinence. Using qualitative template analysis methodology, we identified codes and themes from these open-ended responses from N = 153 adults with AUD. The sample was primarily male (n = 109, 71.2%) and White (n = 98, 64.1%) with an average age of 43.8 years (SD = 11.2). Themes identified included the abstinence length, abstinence reason, relapse, triggers, time of relapse, and treatment. The most common code for abstinence length was “between 1 and 5 years” (n = 55, 35.9%). Other abstinence length codes included “less than 1 year” and “more than 5 years.” Relapse triggers included “family (non-death),” “death of a loved one,” “social,” “economic,” and “treatment-related” reasons. Findings from this study could be used to inform strategies for peer support interventions to assist patients with substance abstinence.
Introduction
In 2021, over 29 million people aged 12 years and older met criteria for having an alcohol use disorder (AUD). 1 AUD is associated with harmful outcomes including increased risk of accidental injury, 2 increased morbidity,3,4 and mortality. 5 Medical conditions such as heart disease and liver disease are also associated with AUD.3,6-9 Further, AUD may precipitate the onset and increased severity of co-occurring mental disorders.10-12 Given these harmful consequences, reducing the negative impact of AUD is vital for the well-being of persons affected by AUD as well as their families and communities.
Abstaining from alcohol decreases harmful outcomes such as cardiac arrhythmia 13 and coronary heart disease. 14 Although alcohol abstinence among people with AUD may result in severe withdrawal symptoms (e.g. seizures and delirium tremens) including some necessitating emergency care, clinical benefits of abstinence can be achieved with appropriate medical monitoring and pharmacologic support.15,16 While abstinence from alcohol is a valuable clinical goal for some persons, 17 harm reduction through decreased drinking is a valuable clinical goal for others.18,19 Similarly, because AUD is a chronic condition, a period of abstinence may be followed by a lapse (restarting the use of a substance) or relapse (returning to similar patterns of substance use).20,21 Alternatively, some persons with AUD may experience long-term periods of abstinence from alcohol after the first treatment attempt. Thus, there is no “one size fits all” approach to reduce the harmful consequences of alcohol use. Given this variability and medical complexity, understanding periods of abstinence among persons with AUD may provide critical insights for future treatment, particularly in settings that provide acute treatment and referral to specialty care.
Emergency departments (EDs) provide acute treatment and referrals. These services are often provided for patients with AUD or AUD-related injuries and medical conditions.22-24 Annual alcohol-related visits to the ED cost approximately 1.2 billion USD and significantly impact medical services. 23 Although persons with acute AUD-related conditions may utilize emergency services for their care, other treatment and service options exist including community-based inpatient services, outpatient services, and self-help groups. According to the National Survey of Drug Use and Health, in 2021, approximately 2 million people received substance use treatment from self-help groups in the U.S. 1 Self-help groups include Self-Management and Recovery Training and Alcoholics Anonymous (AA). AA uses social exchange and incorporates the 12-step recovery model which focuses on abstinence from alcohol.25-27 Despite these available support options in the community, including the widespread presence of AA groups, for many, the ED remains their first contact with AUD treatment infrastructure. Thus, understanding experiences of persons with AUD in the ED may facilitate increased contact with community treatment and decrease ED utilization and costs among these persons. These insights may inform what individuals are seeking and what should be offered/promoted in community treatment.
The present study used qualitative template analysis methodology to explore themes from open-ended responses about previous periods of abstinence during admissions to the ED.28,29 Template analysis provides a structured approach for analyzing qualitative data and extracting common themes. Systematically capturing the perspectives and experiences of abstinence, especially relapse triggers, may facilitate development of interventions to support adults with AUD who are striving toward sustained abstinence.
Materials and Methods
Emergency department intervention
The present study evaluated data from the Screening, Brief Intervention, and Referral to Treatment (SBIRT) program for substance use disorders implemented by the Johns Hopkins Bayview Emergency Department. Intervention data are entered into the electronic health record (Epic Systems) by ED staff, including triage nurses and peer recovery specialists. New admissions to the ED are screened by the triage nurse for illicit substance use during the past 12 months or a score of ⩾ 7 on the Alcohol Use Disorders Identification Test-Consumption (AUDIT-C), a 3-item brief screener for at-risk alcohol use ranging 0-12 with higher scores indicating greater at-risk use.30,31 Individuals who meet either of these criteria are seen by a peer recovery specialist and receive a brief intervention. The peer recovery specialists ask patients both closed- and open-ended questions about substance use, treatment history, and social support to determine if a referral to substance use treatment is necessary. Peer recovery specialists work with the patient’s medical team to refer the patient to treatment if needed. After the patient is discharged from the ED, the peer recovery specialist will follow-up to determine if they were successfully linked to treatment after the referral.
Sample
Data for the present analysis were extracted from the electronic health record using a bulk query of 1,841 individual adult patients (age ⩾18 years) who received a referral to treatment from the ED SBIRT program from July 1, 2017 to July 1, 2019. Extracted data included standardized closed- and open-ended items such as basic demographic information (e.g. age, sex, race, and ethnicity), substance use history, and other variables assessed by the peer recovery specialists (e.g. barriers to treatment, whether patient attended treatment). A quantitative analysis on factors associated with linkage to treatment following ED referral was conducted in a separate study. 32 The present study focused on items regarding substance abstinence. Specifically, during the brief intervention, the peer recovery specialist is prompted by a standardized form with the question, “Has the patient ever had sustained abstinence?” The peer recovery specialist responds to this question with a dichotomous option of “Yes” or “No.” An affirmative response is followed by an open-ended text-box that the peer recovery specialist asks about and then records a description of the prior period of sustained abstinence. This period of sustained abstinence was open to the patient’s own personal interpretation. The sample for the present study includes all patients during the query period that met the following criteria: (1) were included in the quantitative dataset, 32 (2) had an AUD diagnosis documented in the electronic health record, (3) were documented as either attended or did not attend treatment following the referral, (4) indicated “Yes” for having a prior period of abstinence, and (5) had an open-ended response which described their period of abstinence. A consort diagram of this study may be found in the Supplemental Material. The final sample for the present analysis included N = 153 cases.
Data analysis
Descriptive statistics were used to summarize the characteristics of the sample. This study utilized a qualitative template analysis methodology to identify themes in the open-ended responses.28,29 Steps in the template analysis include (1) familiarizing oneself with the open-ended responses, (2) engaging in preliminary coding, (3) arranging themes, (4) creating an initial coding template, (5) code based on the initial coding template while adapting it when necessary, and (6) finalizing the coding template.28,29 Using a template analysis allows researchers to develop a coding template using a bottom-up coding approach and adapt it as needed when new codes and themes emerged outside of our initial research questions. 28 This allows for the flexibility in coding of our data even with our a priori research questions. Although this allows for flexibility with coding, the 6 steps in the template analysis allows for a structured coding process using a team approach.28,29
The narratives were coded by a doctoral-level researcher “ODW” with experience using the template analysis and open-ended thematic methodology33,34 and providing clinical services in Baltimore, MD as a licensed social worker with persons who have a substance use disorder, a master’s level researcher “BL,” and a bachelor’s level researcher “DH.” The study PI “MMS” oversaw the coding and would provide a tie-breaking vote in the event of 3 different codes. The master’s and bachelor’s level researchers were trained in the template analysis methodology by the doctoral-level researcher. The training included coding fictional data unrelated to this study’s topic area. A study dictionary was created with relevant terms to assist the study team in reading through the open-ended narratives. Words in the study dictionary included names of treatment facilities in the greater Baltimore area (which were often referenced in the narratives), medical abbreviations, and terms colloquially used among recovery circles (e.g. sober, sponsor).
The research team coded the data guided by 2 research questions: “How long was their period of abstinence?” and “What were the triggers that caused them to relapse?” To answer question 1, 2 codes were initially used, which included “Abstinence Length: Between 1 and 5 years” and “Abstinence Length: More than 5 years.” A code for less than 1 year of abstinence was added as an emerging theme. Other emerging themes and codes that were unrelated to the primary questions were also identified and coded. All N = 153 narratives were separated into 5 batches. Each batch was coded separately by the 3 primary coders. After coding each batch, the research team would meet to discuss and compare all codes and themes and update the coding template accordingly. After coding the final batch, the research team used the final template to add codes to previous batches. Depending on the content of the narrative, individual narratives could contain multiple codes. Example narratives presented in this article were derived from de-identified data, but additional changes were made where necessary to further protect privacy prior to inclusion as exemplars in the manuscript. For example, exact interpersonal relationships may have been altered (e.g. “family member” in place of “daughter”) and specific treatment facilities were redacted. The Johns Hopkins University Institutional Review Board reviewed the extraction of these data and determined the project to be exempt research.
Results
Sample characteristics
Table 1 describes the sample. Patients had an average age of 43.8 years (SD = 11.2) and were primarily male (n = 109, 71.2%) and White (n = 98, 64.1%). Most of the sample were unemployed (n = 100, 65.4%) and approximately a quarter requested assistance with locating housing services (n = 40, 26.1%) while in the ED. A majority of the sample were previously treated for substance use (n = 121, 79.1%) and were successfully linked to treatment following the ED referral according to data entered by the peer recovery specialists (n = 109, 71.2%). The mean AUDIT-C score was 9.0 (SD = 4.7) with a Cronbach’s alpha of .99. Self-reported substance use other than alcohol during the past 12 months included heroin (n = 26, 17.0%), cocaine (n = 22, 14.4%), and cannabis (n = 19, 12.4%).
Sample characteristics.
Some columns may not equal 100% due to rounding error.
Alcohol Use Disorders Identification Test, Range 0-12 with higher scores indicating greater alcohol risk.
All included patients had an alcohol use disorder. Other substances were not mutually exclusive.
Substance use disorder treatment.
Template analysis
Table 2 provides the final coding template which has the themes, codes, and frequencies of codes identified during this analysis. The themes identified in this study include “Abstinence Length,” “Abstinence Reason,” “Time of Relapse,” “Treatment,” “Relapse Trigger,” and “Other.” The theme “Other” was used to describe codes that could not be included in the primary themes but also had too few similar codes to generate a new theme.
Final qualitative template, theme, and codes.
Abstinence length
We were interested in determining the length of the sustained period of abstinence. The length of abstaining from the substance included a code of “minimal time” to “more than 5 years.” The code minimal time was used for an individual that used the exact wording “minimal time” when they described their prior period of sustained abstinence. Along with our a priori codes “between 1 and 5 years” and “more than 5 years,” other subthemes included “less than 1 year” and “unclear.”
Abstinence length: Less than 1 year
An abstinence length of less than 1 year was coded 79 times in the data. An example includes:
The [patient] states the longest he’s gone without alcohol is 2 weeks.
Abstinence length: Between 1 and 5 years
An abstinence length of between 1 and 5 years was identified 55 times in the data. One example is: [Patient] had 3 years sober prior to last [day of the week]. States their [significant other] left, put a restraining order on them and took their [over $10,000] disability settlement.
Abstinence length: More than 5 years
There were 12 times more than 5 years was coded for abstinence. In one instance: The [patient] was sober for 12 years in the past. They state that they have been drinking for the last 6 years. . . [on] and off.
Abstinence reason
“Abstinence reason” is a second theme that emerged from coding the data. There were several instances in which the narratives explicitly described their motivations for the previous period of abstinence. In some of these narratives, multiple reasons were described as cumulatively being abstinence reasons. Some codes that are found under this theme include “willpower,” “working/worked,” “incarcerated,” and “hobbies.”
Abstinence reason: Willpower
Willpower as an abstinence reason was identified 5 times. In one instance: [Patient] states they had 1 and a half years sober prior to relapse 2 weeks ago. States they did this on their own. States they had the “strongest willpower of anyone I know”. States they have also had several other periods of sobriety without help.
Abstinence reason: Working/worked
Working/worked (regarding employment) was identified as an abstinence reason was identified 4 times. One narrative indicated: The [patient] was sober for 3-4 months at one time last year. He went to meetings and worked a lot.
Abstinence reason: Incarcerated
Being incarcerated and unable to easily access substances was coded 3 times. An example includes: The patient was abstinent for 5 years while in prison. She relapsed 3 years ago.
Abstinence reason: Hobbies
Engaging in hobbies as a reason to remain abstinent was identified 3 times in the data. An example is: The patient was clean and sober for a year and a half. He participated in church, A/A, and stayed busy with his hobbies. He recently found out that the child he thought was his child is not his. This caused him to relapse.
Time of relapse
Time of relapse refers to the time the patient relapsed prior to the emergency department admission. There were other instances in which codes were added which identified an individual relapsing after treatment. The most identified codes in this theme include “1 year ago,” “2 years ago,” and “2 weeks ago.”
Time of relapse: 2 weeks ago
The code which identified relapsing 2 weeks ago was identified 5 times in the data. The following describes one of these instances: The patient stated they had 1 year sobriety and they relapsed 2 weeks ago.
Time of relapse: 1 year ago
Relapsing 1 year ago was coded 12 times in the analyses. The following describes events which preceded the individual relapsing 1 year ago: The patient stated while [in state name] they went into a 28-day treatment facility. They stated they accumulated 10 years of sobriety. She states she lost her home and came to [different state name] and eventually relapsed 1 year ago.
Time of relapse: 2 years ago
Relapsing 2 years ago was coded 8 times. One such example includes: Patient had 3 ½ years sober about 2 years ago. States she achieved this during her time at a 6 month rehab and subsequent admission to [treatment facility] + AA attendance. once [patient] left [treatment facility] she began slowly leaving her AA meetings. Drank shortly afterwards.
Treatment
Treatment is a theme that emerged from the data and referred to the various ways in which substance use treatment was described by narratives in the sample. Two codes were grouped into the following subthemes: treatment types and treatment events. Under treatment type, Attended AA and sponsor were codes we identified. Under treatment attended treatment, “abstinent during treatment,” and “abstinent after treatment” were codes that were identified.
Treatment: Attended AA
The code attended AA was used 17 times when examining the data. An example is: The [patient] has had several 1-year stints of abstinence. On this occasion, he was sober for 6 months. He went to AA meetings and worked a program.
Treatment: Sponsor
Using a sponsor as a form of treatment was described 11 times in the data. The following provided an example of using a sponsor along with other strategies to remain abstinent: The [patient] was sober for 15 months in the past. The [patient] worked a program, had a sponsor, and went to meetings.
Treatment: Attended treatment
Attending treatment at some point in their lives was described 65 times in the data. An example is: [Patient] had 1 year and several months sober roughly 3 years ago. [Patient] states he obtained this after attending [treatment facility] and following up with IOP [intensive outpatient] afterwards. [Patient] was also attending AA meetings.
Treatment: Abstinent during treatment
A period of abstinence during treatment was coded 42 times and an example is: The [patient] was abstinent while in [treatment].
Treatment: Abstinent after treatment
A period of abstinence after treatment was coded 25 times and an example is: The [patient] was sober for 2.5 months after being discharged from [treatment facility]. She is living for an alcoholic [and] eventually she relapsed.
Relapse triggers
We were interested in describing triggers which prompted individuals in this sample to return to previous patterns of substance use. Relapse triggers were grouped into the following subthemes “Relapse Trigger: Family (non-death),” “Relapse Trigger: Death of a loved one,” “Relapse Trigger: Social,” “Relapse Trigger: Economic,” and “Relapse Trigger: Treatment related.” Codes under the theme relapse trigger include: family stressors, family member’s death, other substance users, and discharged from treatment.
Relapse trigger: Family stressors (non-death)
Family stressors that were unrelated to a family member’s death was coded as a relapse trigger 7 times. One example is: [Patient] has several times in the past maintained several months of sobriety. Most recently was at [treatment facility] for less than a week and relapsed yesterday. Affiliates family stressors as precipitating relapse.
Relapse trigger: Family member’s death
A family member’s death was coded 5 times as a relapse trigger. The following example describes a family member’s death preceding a friend’s death which contributed to relapsing: The [patient] was sober after being discharged in [month and year] from [treatment facility] for 5 months. They relapsed when there was a death in the family followed by another death of a friend.
Relapse trigger: Other substance users
Being in close proximity to other substance users was coded 6 times as a relapse reason such as the following example: [Patient] had 3-4 months sober after last admission to [treatment facility] while attending [treatment program]. Part of his relapse [was] brought on by continuing to associate with other drinkers.
Relapse trigger: Discharged from treatment
Being discharged from treatment was identified as a relapse reason 4 times in the data. An example includes: [Patient] had 6 months sober while a patient at [regional psychiatric hospital]. This is the longest sobriety period [patient] claims to have had. [Patient] states he does well in treatment programs but begins drinking again shortly after discharge.
Discussion
This paper describes the patient experiences of a period of sustained abstinence from the perspectives of adults with an AUD admitted to an emergency department. The research team coded the data guided by 2 research questions: “How long was their period of abstinence?” and “What were the triggers that caused them to relapse?” During the coding process, other emerging themes from the open-ended narratives included: abstinence reason, time of relapse, and treatment. We observed different relapse triggers which may be useful to address when supporting persons trying to achieve abstinence.
Abstinence length
Abstinence length codes ranged from 1 week to more than 5 years. This broad range is reflected in the discussions of many recovery groups, in which the concept of “taking it 1 day at a time” has been described for decades.35,36 Each day is often celebrated as another victory when trying to overcome the chronic illness of a substance use disorder. One implication of our observations related to the duration of prior abstinence is that a dichotomous (“yes” or “no”) question as to whether a patient had a prior period of abstinence is insufficient if the desire is for clinicians or researchers to capture only extended periods of abstinence. Given that the duration of abstinence is a known predictor of long-term recovery related outcomes such as overall health, financial status, and social support, greater precision is warranted when assessing the importance of prior periods of abstinence during brief intervention programs. 37
Abstinence reason
The reason for abstinence varied and, in some cases, multiple reasons for abstinence were described. Willpower, employment, incarceration, and hobbies were the most often identified reasons for abstinence. Willpower was the most identified reason for abstinence. Although the construct of willpower is nebulous and lacking in formal empirical characterization, it is sometimes characterized as the use of internal strengths to avoid using a substance.38,39 Potentially related constructs of self-regulation and self-efficacy are associated with substance use abstinence. 40 Strengths-based approaches allow clinicians to focus on an individual’s strengths when addressing an issue such as overcoming a substance use disorder. Clinicians may be able to assist people interested in abstinence by identifying their specific strengths such as willpower and self-regulation, making patients aware of these strengths, devising plans to use their strengths to achieve abstinence, and reinforcing these strengths via positive feedback.
We interpreted the employment and hobbies codes as dedicating time to non-substance-related activities, which may increase the capacity to avoid substance use. This is in line with theoretical and empirical research suggesting that increasing access to reinforcing or enjoyable non-drug-related activities can support long-term recovery.41,42 The present analyses highlight that employment and hobbies may be valuable alternative reinforcers that could be leveraged to promote abstinence. Considering that over 65% of our sample were unemployed, the ED could be an important environment to refer patients to outside agencies that provide employment training services. Our evaluation of relapse demonstrated the need to tailor treatment approaches and referrals according to individual patient needs.
Time of relapse and relapse triggers
Time of relapse ranged from 1 day to 27 years prior to their ED visit, which corresponds to potentially different readiness to change and likelihood of medically significant withdrawal. Reasons for relapse included family stressors, grief, social, economic, and treatment-related reasons. Family and couples counseling may be an effective way to address family stressors and improve substance use related outcomes for adults with an AUD and their families 43 and could be considered as an avenue for treatment referrals from the ED. Stress management techniques may also be beneficial when encountering family related and other general stressors. The need for bereavement support was also identified in this sample, given that death of a loved one was identified as a reason for relapse. While treatment-related reasons, such as treatment discharge, were identified as a reason for relapse, receipt of treatment was associated with sustained abstinence. 17
Treatment
The data identified several codes for attending treatment, being abstinent during treatment, and being abstinent after treatment. Successful treatment for a substance use disorder has been shown to increase the length of abstinence from substances.44-47 However, treatment discontinuation was noted as a trigger for relapse among several patients. Abrupt treatment discontinuation is a particular risk for patients returning to similar patterns of substance use.46-48 More work is needed to ensure patients have access to long-term evidenced-based treatment and to offer continuity of recovery supports through transitions of care.
Strengths and limitations
This study evaluated patient experiences of substance abstinence among persons with AUD collected in a real-world brief intervention occurring in the ED and identified several clinical needs that may shape future referral to treatment programs. The present analysis should be interpreted in the context of both strengths and limitations. The patients included in this sample were adults with AUD who received treatment in an urban ED and who were documented as having attended or not attended subsequent treatment. Although these characteristics allowed us to focus on abstinence and relapse for patients with AUD (who may have unique and medically significant abstinence concerns), and allowed us to describe the overall referral to treatment success of this sub-group, these characteristics may not be generalizable to all populations. Another limitation is the retrospective nature of this study examining preexisting electronic health records rather than structured interviews with patients. Further, abstinence, the focus of the present study, has been criticized as only 1 dimension of successful recovery from AUD 49 with controlled drinking or other harm reduction as alternative clinical goals.18,19 Unfortunately, there were no questions in this secondary dataset that could be analyzed to assess controlled drinking. Future qualitative research may compare controlled drinking and abstinence goals among persons with AUD. The weaknesses of the study are offset by the fact that the data were collected from a large sample of open-ended responses collected by real-world clinicians implementing a structured brief intervention interview that was integrated into the electronic health record. The use of a standardized data set from peer recovery coach workflows in the ED performing usual clinical care contributes to the external validity and real-world implications of our findings. Thus, the present paper provides individuals with a goal of abstinence and their providers with considerations for brief intervention, referral to treatment, and long-term considerations for AUD recovery.
Conclusion
Different themes emerged when examining prior periods of abstinence. Our foci were abstinence length and relapse triggers. In our sample, we found that reported abstinence length varied considerably from 6 days to more than 5 years. This broad variability points to the experiences of abstinence. Relapse triggers were thematically family, death of a loved one, social, economic, and treatment related. Stressors related to these themes should be screened for and addressed when service providers and clinicians provide services to individuals abstaining from substance use. An example may include screening for the recent death of a loved one and providing a referral to individual or group bereavement therapy. As it relates to family as a relapse trigger, interventions could be tailored to an individual and may include trauma-focused individual therapy, identifying stress reduction strategies, couples/family therapy, or support groups. Relapse triggers are multiple, variable, and compounding, and there is additional need to empirically evaluate effective interventions that can mitigate stressors such as those described in the ED narratives in the present study to promote continued abstinence among patients with AUD.
Supplemental Material
sj-docx-1-sat-10.1177_11782218231162468 – Supplemental material for Prior Periods of Abstinence Among Adults With an Alcohol Use Disorder: A Qualitative Template Analysis
Supplemental material, sj-docx-1-sat-10.1177_11782218231162468 for Prior Periods of Abstinence Among Adults With an Alcohol Use Disorder: A Qualitative Template Analysis by Orrin D. Ware, Breanna Labos, Daniella Hudgins, Nathan A. Irvin, Megan E. Buresh, Cecilia L. Bergeria and Mary M. Sweeney in Substance Abuse: Research and Treatment
Footnotes
Acknowledgements
The authors thank Wande Kotun, Phoebe Rostov, Joy Haywood, Eric Trojan, and Ayana Andrews for their contributions to the peer support brief intervention program in the ED. We thank Pratima Kshetry and Nazanin Yousefzadeh for their assistance with the extraction and coding of the data from the electronic health record. We thank August F. Holtyn for her assistance with reviewing the open-ended data. We also thank the Mosaic Group for providing structured training to the peer recovery coaches.
Funding:
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This project was supported by National Institutes of Health (NIH) (Bethesda, MD), National Institute on Drug Abuse (NIDA) R03DA048913 awarded to Mary M. Sweeney while at Johns Hopkins University. Support for Orrin D. Ware was provided by NIDA T32DA007209 awarded to George E. Bigelow, Eric C. Strain and Elise M. Weerts. NIH/NIDA had no role in the study design, in the collection, analysis, or interpretation of data, in the writing of the report, or in the decision to submit the article for publication. The opinions expressed in this article are the authors’ own and do not reflect the view of the National Institutes of Health, the Department of Health and Human Services, or the United States government.
Declaration of Conflicting Interests:
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Author Note
Mary M. Sweeney is now employed by the National Institutes of Health, National Institute of Mental Health. This article was prepared while Mary M. Sweeney was employed at Johns Hopkins University.
Author Contributions
All authors contributed to the design, preparation, and editing of this article.
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References
Supplementary Material
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