Erin Stringfellow joined the ITA in October 2019. She holds a PhD in Social Work from the Brown School at Washington University in St. Louis and a Master of Social Work from the University of Michigan, where she also earned her BA. She specializes in using qualitative and system dynamics methods to develop sustainable interventions and policies that support recovery from addiction.
Prior to joining the ITA, Dr. Stringfellow was a research scientist and assistant research professor at the Missouri Institute of Mental Health at the University of Missouri, St. Louis, where she worked with a dedicated, passionate team to conduct evaluation and research of federally-funded opioid-related grants. She has held multiple affiliations with the Social System Design Lab since 2013, where she developed skills and expertise in community-based system dynamics projects addressing homelessness, behavioral health policy, and opioid overdoses.
Dr. Stringfellow is excited to return to the Boston area. Previously, she worked as a research associate at the Boston Health Care for the Homeless Program from 2008-2012.
She is working with Dr. Mohammad Jalali (“MJ”) to develop system dynamics models to improve policies focused on substance use prevention, harm reduction, treatment for disorder, and recovery.
Selected Publications
Stringfellow, Erin J; Dong, Huiru; Khatami, Seyedeh Nazanin; Lee, Hannah; Jalali, Mohammad S
In: Addiction, 2025, ISSN: 1360-0443.
@article{pmid39994821,
title = {The association between buprenorphine doses above 16 milligrams and treatment retention in a multi-payer national sample in the United States, 2014 to 2021},
author = {Erin J Stringfellow and Huiru Dong and Seyedeh Nazanin Khatami and Hannah Lee and Mohammad S Jalali},
doi = {10.1111/add.70002},
issn = {1360-0443},
year = {2025},
date = {2025-02-01},
journal = {Addiction},
abstract = {BACKGROUND AND AIMS: Buprenorphine-naloxone reduces overdose deaths in people with opioid use disorder (OUD). Treatment retention increases with higher daily doses. No national studies exist on retention's association with 24, 32 and 40 mg. This study aimed to: (1) estimate the effect on treatment retention of buprenorphine-naloxone doses between 4 and 40 mg compared with 16; and (2) compare the effect on treatment retention of 24, 32 and 40 mg doses.nnDESIGN: Observational cohort study in a national, multi-payer sample of prescription claims (IQVIA) of episodes involving buprenorphine-naloxone for OUD. Incident episodes started between 1 January 2014 and 31 March 2020, with a washout of 180 days. New episodes started with a 14+ day gap between prescriptions.nnSETTING: United States of America.nnPARTICIPANTS: The sample involved 620 229 episodes across 498 879 patients [42.3% female; mean age 37.9 (standard deviaion: 11.9)] who were dispensed prescriptions of buprenorphine-naloxone for OUD.nnMEASUREMENTS: The exposure was the maximum daily dose of buprenorphine-naloxone reached in the first 30 days of an episode, ranging from 4 to 40 mg. The outcome, treatment retention, was defined as having an active prescription at 1, 3, 6, 12, or 18 months. Covariates were age, sex, race and ethnicity, primary payer, and year of episode initiation.nnFINDINGS: Daily doses of 24, 32 and 40 mg increased retention compared with 16 mg at 1-18 months [adjusted odds ratio (aOR) range = 1.17; 95% confidence interval (CI) = 1.14, 1.20 at 18 months to 1.52 (CI = 1.49, 1.54) at 1 month, both for 24 mg]. In pairwise comparisons, 32 mg was favorable to 24 mg at 6, 12 and 18 months [aOR = 1.06 (95% CI = 1.02, 1.10) at 6 months; aOR = 1.09 (95% CI = 1.04, 1.14) at 12 months; aOR = 1.12 (95% CI = 1.06, 1.19) at 18 months], and 40 mg was favorable to 24 mg at 12 and 18 months [aOR = 1.10 (95% CI = 1.01, 1.21) at 12 months; aOR = 1.18 (95% CI = 1.06, 1.30) at 18 months].nnCONCLUSIONS: Daily buprenorphine-naloxone doses of 24 mg appear to be associated with increased treatment retention compared with 16 mg and, for 6+ month episodes, 32 and 40 mg appear to be associated with increased retention compared with 24 mg.},
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Dong, Huiru; Stringfellow, Erin J; Jalali, Mohammad S
State-level racial and ethnic disparities in buprenorphine treatment duration in the United States Journal Article
In: Am J Addict, vol. 34, no. 1, pp. 69-74, 2025, ISSN: 1521-0391.
@article{pmid39107678,
title = {State-level racial and ethnic disparities in buprenorphine treatment duration in the United States},
author = {Huiru Dong and Erin J Stringfellow and Mohammad S Jalali},
doi = {10.1111/ajad.13638},
issn = {1521-0391},
year = {2025},
date = {2025-01-01},
urldate = {2024-08-01},
journal = {Am J Addict},
volume = {34},
number = {1},
pages = {69-74},
abstract = {BACKGROUND AND OBJECTIVES: National trends reveal a concerning escalation in racial and ethnic disparities in buprenorphine treatment duration for opioid use disorder. However, the extent of such disparities at the state level remains largely unexplored. This study aims to examine such disparities at the state level.nnMETHODS: We analyzed 9,040,620 buprenorphine prescriptions dispensed between January 2011 and December 2020 from IQVIA Longitudinal Prescription data. The primary outcome was the difference in median treatment duration between White people and racial and ethnic minorities. We also included a second outcome measurement to quantify the difference in median treatment duration among episodes lasting ≥180 days. Using quantile regressions, we examined racial and ethnic disparities in treatment duration, adjusting for the patient\'s age, sex, payment type, and calendar year of the treatment episode. All analyses were conducted at the state level.nnRESULTS: Our study revealed substantial statewide variations in racial and ethnic disparities. Specifically, 21 states showed longer treatment durations for White people across all episodes, and eight states displayed similar trends among episodes lasting ≥180 days. Five states exhibited longer treatment durations for White people in both overall and long-term episodes. Fifteen states showed no racial and ethnic disparities.nnCONCLUSION AND SCIENTIFIC SIGNIFICANCE: These results are among the first to indicate substantial statewide variations in racial and ethnic disparities in buprenorphine treatment episode duration, providing a critical foundation for targeted interventions to enhance buprenorphine treatment, especially in states confronting such pronounced racial and ethnic disparities.},
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Lee, Hannah; Otero-Leon, Daniel; Dong, Huiru; Stringfellow, Erin J; Jalali, Mohammad S
Uncovering Patterns in Overdose Deaths: An Analysis of Spike Identification in Fatal Drug Overdose Data in Massachusetts, 2017-2023 Journal Article
In: Public Health Rep, pp. 333549241299613, 2024, ISSN: 1468-2877.
@article{pmid39717009,
title = {Uncovering Patterns in Overdose Deaths: An Analysis of Spike Identification in Fatal Drug Overdose Data in Massachusetts, 2017-2023},
author = {Hannah Lee and Daniel Otero-Leon and Huiru Dong and Erin J Stringfellow and Mohammad S Jalali},
doi = {10.1177/00333549241299613},
issn = {1468-2877},
year = {2024},
date = {2024-12-01},
journal = {Public Health Rep},
pages = {333549241299613},
abstract = {OBJECTIVES: Yearly rolling aggregate trends or rates are commonly used to analyze trends in overdose deaths, but focusing on long-term trends can obscure short-term fluctuations (eg, daily spikes). We analyzed data on spikes in daily fatal overdoses and how various spike detection thresholds influence the identification of spikes.nnMATERIALS AND METHODS: We used a spike detection algorithm to identify spikes among 16 660 drug-related overdose deaths (from any drug) reported in Massachusetts' vital statistics from 2017 through 2023. We adjusted the parameters of the algorithm to define spikes in 3 distinct scenarios: deaths exceeding 2 adjusted moving SDs above the 7-, 30-, and 90-day adjusted moving average.nnRESULTS: Our results confirmed the on-the-ground observation that there are days when many more people die of overdoses than would be expected based on fluctuations due to differences among people alone. We identified spikes on 5.8% to 20.6% of the days across the 3 scenarios, annually, constituting 11.1% to 31.6% of all overdose deaths. The absolute difference in percentage points of days identified as spikes varied from 5.2 to 11.5 between 7- and 30-day lags and from 0 to 4.6 between 30- and 90-day lags across years. When compared with the adjusted moving average across the 3 scenarios, in 2017 an average of 3.9 to 5.5 additional deaths occurred on spike days, while in 2023 the range was 3.7 to 6.0.nnPRACTICE IMPLICATIONS: A substantial percentage of deaths occurred annually on spike days, highlighting the need for effectively monitoring short-term overdose trends. Moreover, our study serves as a foundational analysis for future research into exogenous events that may contribute to spikes in overdose deaths, aiming to prevent future deaths.},
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Lim, Tse Yang; Dong, Huiru; Stringfellow, Erin; Hasgul, Zeynep; Park, Ju; Glos, Lukas; Kazemi, Reza; Jalali, Mohammad S.
Temporal and spatial trends of fentanyl co-occurrence in the illicit drug supply in the United States: a serial cross-sectional analysis Journal Article
In: The Lancet Regional Health - Americas, vol. 39, 2024, ISSN: 2667-193X.
@article{Lim2024,
title = {Temporal and spatial trends of fentanyl co-occurrence in the illicit drug supply in the United States: a serial cross-sectional analysis},
author = {Tse Yang Lim and Huiru Dong and Erin Stringfellow and Zeynep Hasgul and Ju Park and Lukas Glos and Reza Kazemi and Mohammad S. Jalali},
doi = {10.1016/j.lana.2024.100898},
issn = {2667-193X},
year = {2024},
date = {2024-11-00},
journal = {The Lancet Regional Health - Americas},
volume = {39},
publisher = {Elsevier BV},
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Dong, Huiru; Stringfellow, Erin J; Russell, Alton; Jalali, Mohammad S
State Mandates On Naloxone Coprescribing Associated With Short-Term Increase In Naloxone Codispensing Journal Article
In: Health Aff (Millwood), vol. 43, no. 9, pp. 1319–1328, 2024, ISSN: 2694-233X.
@article{pmid39226505,
title = {State Mandates On Naloxone Coprescribing Associated With Short-Term Increase In Naloxone Codispensing},
author = {Huiru Dong and Erin J Stringfellow and Alton Russell and Mohammad S Jalali},
doi = {10.1377/hlthaff.2023.01667},
issn = {2694-233X},
year = {2024},
date = {2024-09-01},
journal = {Health Aff (Millwood)},
volume = {43},
number = {9},
pages = {1319--1328},
abstract = {In the midst of the opioid crisis in the US, efforts to mitigate overdose risks have become paramount, leading some states to introduce mandates for coprescribing the life-saving overdose reversal drug naloxone. These mandates were designed to specifically address people receiving opioid analgesics who had an elevated risk for overdose. This included people receiving high opioid dosages, those concurrently using benzodiazepines, or those with a history of substance use disorder or overdose. Using a nationally representative, multipayer cohort of patients receiving prescription opioids, we investigated how naloxone codispensing rates changed at the state level from 2016 to 2021 among patients with an elevated risk for overdose. Then we used controlled interrupted time series analyses to assess mandates' longitudinal impact on naloxone codispensing in ten states that implemented mandates. We observed an immediate and significant increase in the naloxone codispensing rates in eight states after the implementation of mandates. Nevertheless, in five of these states, the codispensing rates exhibited a subsequent downward trend after the initial increase. State mandates show potential for improving naloxone codispensing; however, mandates alone might not be adequate for sustained change. Further research is needed to identify strategies complementing and enhancing the impact of mandates in combating the overdose crisis.},
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Lim, Tse Yang; Keyes, Katherine M; Caulkins, Jonathan P; Stringfellow, Erin J; Cerdá, Magdalena; Jalali, Mohammad S
Improving Estimates of the Prevalence of Opioid Use Disorder in the United States: Revising Keyes et al Journal Article
In: J Addict Med, vol. 18, no. 6, pp. 705-710, 2024, ISSN: 1935-3227.
@article{pmid39221814,
title = {Improving Estimates of the Prevalence of Opioid Use Disorder in the United States: Revising Keyes et al},
author = {Tse Yang Lim and Katherine M Keyes and Jonathan P Caulkins and Erin J Stringfellow and Magdalena Cerd\'{a} and Mohammad S Jalali},
doi = {10.1097/ADM.0000000000001375},
issn = {1935-3227},
year = {2024},
date = {2024-09-01},
urldate = {2024-09-01},
journal = {J Addict Med},
volume = {18},
number = {6},
pages = {705-710},
abstract = {OBJECTIVES: The United States faces an ongoing drug overdose crisis, but accurate information on the prevalence of opioid use disorder (OUD) remains limited. A recent analysis by Keyes et al used a multiplier approach with drug poisoning mortality data to estimate OUD prevalence. Although insightful, this approach made stringent and partly inconsistent assumptions in interpreting mortality data, particularly synthetic opioid (SO)-involved and non-opioid-involved mortality. We revise that approach and resulting estimates to resolve inconsistencies and examine several alternative assumptions.nnMETHODS: We examine 4 adjustments to Keyes and colleagues\' estimation approach: (A) revising how the equations account for SO effects on mortality, (B) incorporating fentanyl prevalence data to inform estimates of SO lethality, (C) using opioid-involved drug poisoning data to estimate a plausible range for OUD prevalence, and (D) adjusting mortality data to account for underreporting of opioid involvement.nnRESULTS: Revising the estimation equation and SO lethality effect (adj. A and B) while using Keyes and colleagues\' original assumption that people with OUD account for all fatal drug poisonings yields slightly higher estimates, with OUD population reaching 9.3 million in 2016 before declining to 7.6 million by 2019. Using only opioid-involved drug poisoning data (adj. C and D) provides a lower range, peaking at 6.4 million in 2014-2015 and declining to 3.8 million in 2019.nnCONCLUSIONS: The revised estimation equation presented is feasible and addresses limitations of the earlier method and hence should be used in future estimations. Alternative assumptions around drug poisoning data can also provide a plausible range of estimates for OUD population.},
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Dong, Huiru; Stringfellow, Erin J; Russell, W Alton; Bearnot, Benjamin; Jalali, Mohammad S
Impact of Alternative Ways to Operationalize Buprenorphine Treatment Duration on Understanding Continuity of Care for Opioid Use Disorder Journal Article
In: Int J Ment Health Addict, vol. 22, no. 4, pp. 2285–2290, 2024, ISSN: 1557-1874.
@article{pmid39629044,
title = {Impact of Alternative Ways to Operationalize Buprenorphine Treatment Duration on Understanding Continuity of Care for Opioid Use Disorder},
author = {Huiru Dong and Erin J Stringfellow and W Alton Russell and Benjamin Bearnot and Mohammad S Jalali},
doi = {10.1007/s11469-022-00985-w},
issn = {1557-1874},
year = {2024},
date = {2024-08-01},
journal = {Int J Ment Health Addict},
volume = {22},
number = {4},
pages = {2285--2290},
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Dong, Huiru; Stringfellow, Erin J; Russell, W Alton; Bearnot, Benjamin; Jalali, Mohammad S
Impact of Alternative Ways to Operationalize Buprenorphine Treatment Duration on Understanding Continuity of Care for Opioid Use Disorder Journal Article
In: Int J Ment Health Addict, vol. 22, no. 4, pp. 2285–2290, 2024, ISSN: 1557-1874.
@article{pmid39629044b,
title = {Impact of Alternative Ways to Operationalize Buprenorphine Treatment Duration on Understanding Continuity of Care for Opioid Use Disorder},
author = {Huiru Dong and Erin J Stringfellow and W Alton Russell and Benjamin Bearnot and Mohammad S Jalali},
doi = {10.1007/s11469-022-00985-w},
issn = {1557-1874},
year = {2024},
date = {2024-08-01},
journal = {Int J Ment Health Addict},
volume = {22},
number = {4},
pages = {2285--2290},
keywords = {},
pubstate = {published},
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Stringfellow, Erin J; Lim, Tse Yang; Dong, Huiru; Zhang, Ziyuan; Jalali, Mohammad S
In: Addiction, vol. 118, no. 11, pp. 2215-2219, 2023, ISSN: 1360-0443.
@article{pmid37434347b,
title = {The association between longitudinal trends in receipt of buprenorphine for opioid use disorder and buprenorphine-waivered providers in the United States},
author = {Erin J Stringfellow and Tse Yang Lim and Huiru Dong and Ziyuan Zhang and Mohammad S Jalali},
doi = {10.1111/add.16291},
issn = {1360-0443},
year = {2023},
date = {2023-11-01},
urldate = {2023-07-01},
journal = {Addiction},
volume = {118},
number = {11},
pages = {2215-2219},
abstract = {AIMS, DESIGN AND SETTING: We sought to describe longitudinal trends in buprenorphine receipt and buprenorphine-waivered providers in the United States from 2003 to 2021 and measure whether the relationship between the two differed after capacity-building strategies were enacted nationally in 2017. This was a retrospective study of two separate cohorts covering the years 2003-21, testing whether the association between two trends in these cohorts changed comparing 2003 to 2016 and from 2017 to 2021, among buprenorphine providers in the United States, regardless of treatment setting. Patients receiving dispensed buprenorphine at retail pharmacies.nnPARTICIPANTS: All providers who have obtained a waiver to prescribe buprenorphine in the United States, and an estimate of the annual number of patients who had buprenorphine for opioid use disorder (OUD) dispensed to them at a retail pharmacy.nnMEASUREMENTS: We synthesized and summarized data from multiple sources to assess the cumulative number of buprenorphine-waivered providers over time. We used national-level prescription data from IQVIA to estimate annual buprenorphine receipt for OUD.nnFINDINGS: From 2003 to 2021, the number of buprenorphine-waivered providers in the United States increased from fewer than 5000 in the first 2 years of Food and Drug Administration (FDA) approval to more than 114 000 in 2021, while patients receiving buprenorphine products for OUD increased from approximately 19 000 to more than 1.4 million. The strength of association between waivered providers and patients is significantly different before and after 2017 (P \< 0.001). From 2003 to 2016, for each additional provider, there was an average increase of 32.1 [95% confidence interval (CI) = 28.7-35.6] patients, but an increase of only 4.6 (95% CI= 3.5-5.7) patients for each additional provider, beginning in 2017.nnCONCLUSIONS: In the United States, the relationship between the rates of growth in buprenorphine providers and patients became weaker after 2017. While efforts to increase buprenorphine-waivered providers were successful, there was less success in translating that into significant increases in buprenorphine receipt.},
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Vivas-Valencia, Carolina; Dong, Huiru; Stringfellow, Erin J; Russell, W Alton; Morgan, Jake R; Tadrous, Mina; Jalali, Mohammad S
Factors Associated With Abrupt Discontinuation of Long-Term High-Dose Opioid Treatment Journal Article
In: JAMA Netw Open, vol. 6, no. 11, pp. e2341416, 2023, ISSN: 2574-3805.
@article{pmid37921772,
title = {Factors Associated With Abrupt Discontinuation of Long-Term High-Dose Opioid Treatment},
author = {Carolina Vivas-Valencia and Huiru Dong and Erin J Stringfellow and W Alton Russell and Jake R Morgan and Mina Tadrous and Mohammad S Jalali},
doi = {10.1001/jamanetworkopen.2023.41416},
issn = {2574-3805},
year = {2023},
date = {2023-11-01},
journal = {JAMA Netw Open},
volume = {6},
number = {11},
pages = {e2341416},
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