Biography

My research unpacks how the intersection of neighborhood, social, and digital spaces affect mental, behavioral, and sexual health, digital health interventions, and access to health services. Previously funded by an F31 training fellowship through the National Institute of Child Health and Human Development, my dissertation work examines how neighborhood, social, and digital spaces influence HIV risk and the effectiveness of a digital pre-exposure prophylaxis adherence intervention among sexual and gender minority adolescents. Currently funded by a T32 fellowship through the National Institute on Aging, I am developing and evaluating digital mindfulness interventions for emerging adults with social media addiction and caregivers of persons living with dementia. With a multidisciplinary background in epidemiology, biostatistics, game design, human-computer interaction, and philosophy of science, my long-term goal is to design and robustly evaluate digital health interventions to improve mental and behavorial for individuals across the lifespan

In my free time I love to cook, play and stream video games, listen and play music, and enjoy time with my family and friends.

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Interests
  • Mental & Behavorial Health
  • Digital Interventions
  • Real World Data
Education

  • PhD in Population Health, 2018 - 2024

    Northeastern University

  • MS Game Science and Design, 2015 - 2017

    Northeastern University

  • BS Psychology, 2009 - 2013

    SUNY Buffalo

  • BA English Literature, 2009 - 2013

    SUNY Buffalo

Skills

Python

Manage, Process, Engineer, and Clean Data

R

Statistical Modeling and Data Visualizations

Statistics

Regression, Multilevel Modeling, Causal Inference and Mediation Analysis, Machine Learning

GIS

Mapping and Spatial Analysis

LaTeX

Manuscript Development

Projects

*
All Access to Health Services Digital Interventions
Neighborhood and digital immersion effects on PrEP adherence in young sexual and gender minorities who have sex with men
Funded by NICHD, grant #1F31HD108046-01A1
Neighborhood and digital immersion effects on PrEP adherence in young sexual and gender minorities who have sex with men
Understanding spatial access to medications assisted treatment for opioid use disorder
Funded by Boston Area Research Initiative, Research Seed Grant
Understanding spatial access to medications assisted treatment for opioid use disorder

Featured Publications

Michael P Williams, Justin Manjourides, Louisa H Smith, Crissi B Rainer, Lisa B Hightow-Weidman, Danielle F Haley
July, 2024
Digital intervention engagement mediates the relationship between intrapersonal measures and pre-exposure prophylaxis adherence: a secondary analysis of a randomized controlled trial of sexual and gender minority youth on pre-exposure prophylaxis

BACKGROUND: Digital health interventions (DHIs) for Pre-Exposure Prophylaxis (PrEP) in young sexual and gender minority men who have sex with men (YSGMMSM) show promise for reducing HIV burden. Effectively engaging (engagement sufficient to solicit PrEP adherence) YSGMMSM is an ongoing challenge.
METHODS: This secondary analysis of the P3 (Prepared, Protected, emPowered: a digital PrEP adherence intervention) randomized controlled trial (RCT) utilized causal mediation to quantify whether and to what extent baseline survey measures of phone and phone app usage, mental health, and sociodemographics were related to effective engagement for PrEP adherence in YSGMMSM. Of 246 YSGMMSM participants aged 16-24 in the primary RCT, 140 participants were eligible for the present analysis (retained at folloâ??w-up, received DHI condition, complete trial data). Participants earned and lost US currency for daily usage/non-usage of P3; dollars accrued by 3 months was used to measure engagement. PrEP non-adherence was measured via blood serum levels consistent with textless4 doses weekly at 3-month follow-up. Logistic regression was used in a causal mediation approach to estimate the total effects of baseline survey measures, represented as non-adherence odds ratios (NAR), and direct and indirect effects mediated by engagement.
RESULTS: Engagement was strongly related to the outcome: for every $1 earned above the mean ($96), participants had 1.6% (NAR=0.984, 95% CI=0.97,0.99) lower odds of PrEP non-adherence. Frequently using phone apps to track health information was associated with a 71% (NAR=0.29, 95% CI=0.06,0.96) lower odds of PrEP non-adherence. This was overwhelmingly a direct effect, not mediated by engagement, with a percent mediated (PM) of 1%. Participants with depressive symptoms and anxious symptoms had 3.4 (NAR=3.42, CI=0.95,12.00) and 3.5 (NAR=3.51, CI=1.06,11.55) higher odds of non-adherence to PrEP at 3 months, respectively. Anxious symptoms largely operated through P3 engagement (PM=51%).
CONCLUSIONS: P3 engagement was strongly related to lower odds of PrEP non-adherence. Several measures were related to effective engagement which suggests that PrEP adherence DHIs for YSGMMSM should tailor intervention content to emphasize engagement facilitators and abate engagement barriers. Evaluating effective engagement in DHIs with causal mediation approaches provides a clarifying and mechanistic view of how DHIs impact health behavior.
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Publications

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Michael Williams, Matt Mahlan, Connor Holmes, Magdalena Pankowska, Manjot Kaur, Aderonke Ilegbusi, Danielle F. Haley (2025). Accuracy Differences in Cannabis Retailer Information Ascertained from Webservices and Government-Maintained State Registries Across US States Legalizing the Sale of Cannabis in 2019. Cannabis.

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Danielle F. Haley, Brooke W. Bullington, Phyllis Tien, Andrea K. Knittel, Julie Bobitt, Mirjam-Colette Kempf, Morgan Philbin, David B. Hanna, StarrLa’diamond Lindsey, Seble Kassaye, Jack DeHovitz, Mardge Cohen, Gina Wingood, Deborah L. Jones, Michael P. Williams, Richard J. Wang, Andrew Edmonds (2025). Patterns of Cannabis Use among Women With HIV in the United States. AIDS and Behavior.

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Michael P. Williams, Justin Manjourides, Louisa H. Smith, Crissi B. Rainer, Lisa Hightow-Weidman, Danielle F. Haley (2025). Neighborhood Disadvantage, Syndemic Conditions, and PrEP Non-Adherence in Young Sexual and Gender Minority Men. AIDS and Behavior.

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Michael P. Williams, Justin Manjourides, Louisa H. Smith, Crissi B. Rainer, Lisa B. Hightow-Weidman, Danielle F. Haley (2025). Studying the Digital Intervention Engagement–Mediated Relationship Between Intrapersonal Measures and Pre-Exposure Prophylaxis Adherence in Sexual and Gender Minority Youth: Secondary Analysis of a Randomized Controlled Trial. Journal of Medical Internet Research.

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Noelle M. St. Vil, Danielle F. Haley, Brooke Montgomery, Michael Williams, Lakeshia Watson, Shuaiqi Zhang, Gina M. Wingood (2024). An Exploration of Geographic Access to Substance Use Treatment Programs and Violence Against Women. Journal of Interpersonal Violence.

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Michael P Williams, Justin Manjourides, Louisa H Smith, Crissi B Rainer, Lisa B Hightow-Weidman, Danielle F Haley (2024). Digital intervention engagement mediates the relationship between intrapersonal measures and pre-exposure prophylaxis adherence: a secondary analysis of a randomized controlled trial of sexual and gender minority youth on pre-exposure prophylaxis.

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Connor Holmes, Laura Senier, Claire Yu, Michael P Williams, Danielle F Haley (2021). "\It fills the glass somewhat\": Examining the psychosocial gratifications of dating apps for transgender and gender non-conforming individuals during COVID-19.

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Michael P Williams, Aderonke Ilegbusi, Connor Holmes, Magdalena Pankowska, Andie Oates, Kyle Nameth, Haley Danielle (2021). State-level differences in validity of cannabis retailer locations ascertained from online listings and government-maintained state registries.

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Hannah Listerud, Steven Meanley, Jose Bauermeister, Lisa Hightow-Weidman, Michael Williams, T Seblework, J Knies, R Galloway, P Valente, Katie Biello, J Hill-Rorie, J Dormitzer, D Flores, K Mayer, Robin Stevens (2020). Natural language processing and content analysis of youth’s social media posts to inform implementation of next generation HIV prevention modalities.

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Magda Pankowska, Danielle Haley, Carmel Salhi, Aderonke Ilegbusi, Michael Williams (2020). Availability of HIV and Hepatitis C testing at drug and alcohol treatment facilities offering medications for opioid use disorder..

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Danielle Haley, Michael Williams, Stephanie Beane, Manjot Kaur, Magdalena Pankowska, Hannah LF Cooper, Sabriya Linton, Andrew Edmonds, Vivian Go, Daniel Kim, Leo Beletsky, Zev Ross, Adaora A. Adimora, Daniel Bauer, Julia Sabrick, Jean McGuire, Janet Cummings (2019). Association between census block group poverty and geographic accessibility of drug and alcohol treatment facilities accepting Medicaid. American Public Health Association.

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Xiying Wang, Tiffany Knearem, Fanlu Gui, Srishti Gupta, Haining Zhu, Michael Williams, John M. Carroll (2018). The Safety Net of Aging in Place: Understanding How Older Adults Construct, Develop, and Maintain Their Social Circles. Proceedings of the 12th EAI International Conference on Pervasive Computing Technologies for Healthcare.

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Xiyang Wang, Tiffany Knearem, Fanlu Gui, Srishti Gupta, Haining Zhu, Michael Williams, J. M. Carroll (2018). A Safety Net: How Older Adults Build and Maintain Interpersonal Relationships. ACM Transactions on Computer-Human Interaction.

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Michael Williams, Anurag Sarkar, Seth Cooper (2017). Predicting Human Computation Game Scores with Player Rating Systems. Entertainment Computing – ICEC 2017.

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Anurag Sarkar, Michael Williams, Sebastian Deterding, Seth Cooper (2017). Engagement Effects of Player Rating System-based Matchmaking for Level Ordering in Human Computation Games. Proceedings of the 12th International Conference on the Foundations of Digital Games.

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Michael Williams, Hassen Gharbi, Aybike Ulusan, Ozlem Ergun, Zhu Xiaofeng, Shiyu Zhang, Casper Harteveld (2016). Toward Human in the Loop Optimization Through Game-Based Experiments. Proceedings of the 2016 Annual Symposium on Computer-Human Interaction in Play Companion Extended Abstracts.

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