Skip to Main Content

Joshua Wallach, PhD, MS

Assistant Professor of Epidemiology (Environmental Health)



Dr. Wallach’s research focuses on synthesizing, evaluating, and establishing the best evidence to inform research, regulatory, and public health decisions. His primary area of research, known as meta-research (i.e. the study of research itself), includes the key thematic areas of research methods, reporting/transparency, and reproducibility. Dr. Wallach’s research interests include meta-analytical methodology, evaluating study biases, clinical trial design/conduct, pharmacoepidemiology, and regulatory science.

His work with the Collaboration for Research Integrity and Transparency (CRIT) at Yale focuses on evaluating the tools, standards, and approaches used to assess the safety, efficacy, quality, and performance of FDA-regulated products using epidemiologic and meta-research methods. Dr. Wallach is also a Faculty Affiliate of the Meta-Research Innovation Center at Stanford (METRICS).

Dr. Wallach is currently leading or collaborating on numerous studies, including meta-analyses of environmental exposures and clinical interventions, real world data analyses of medications, and meta-research projects with students.

Recent publications with students:

Joshua Skydel (Medical student at Tufts University School of Medicine):

Skydel JJ, Luxkaranayagam AT, Dhruva SS, Ross JS, Wallach JD. Analysis of Postapproval Clinical Trials of Therapeutics Approved by the US Food and Drug Administration Without Clinical Postmarketing Requirements or Commitments. JAMA Netw Open. 2019;2(5):e193410.

Patrick Liu (Medical student at Yale School of Medicine):

Liu P, Ioannidis JPA, Ross JS, et al. Age-treatment subgroup analyses in Cochrane intervention reviews: a meta-epidemiological study. BMC Med. 2019;17(1):188.

Liu P, Ross JS, Ioannidis JP, Dhruva SS, Vasiliou V, Wallach JD. Prevalence and significance of race and ethnicity subgroup analyses in Cochrane intervention reviews. Clin Trials. 2019:1740774519887148.

Lingzhi Chu (Doctoral student in the Environmental Health Sciences Department at the Yale School of Public Health)

Chu L, Ioannidis JPA, Egilman AC, Vasiliou V, Ross JS, Wallach JD. Vibration of effects in epidemiologic studies of alcohol consumption and breast cancer risk. Int J Epidemiol. 2020

Emma Deary (Undergraduate student at Wellesley College, Summer Research Experience in Environmental Health Sciences).

Deary EC, Ross JS, Nyhan K, Wallach JD. Conflicts of Interest Among Authors of Published Cannabidiol Articles, 2014-2019. Annals Of Internal Medicine 2020.

Education & Training

  • Postdoctoral Research Fellow / Research Associate III
    Yale University (2018)
  • PhD
    Stanford University, Epidemiology and Clinical Research (2017)
  • MS
    Stanford University, Epidemiology and Clinical Research (2017)

Departments & Organizations