About

Sam Clark is a demographer, epidemiologist, and data scientist who develops new methods and conducts research in the fields of demography and epidemiology. He is a professor in the Department of Sociology at The Ohio State University and is a faculty affiliate of the Institute for Population Research and the Translational Data Analytics Institute at OSU. His work includes improving verbal autopsy as a tool to measure the burden of disease, developing mathematical models of human mortality, and creating indirect estimates of child mortality and small-area estimates of mortality. Clark has been actively involved in projects related to estimating the prevalence of COVID-19 and excess deaths during the pandemic, working closely with large teams at OSU and the Ohio State Department of Health. He leads the openVA Team, which develops open-source software to implement new methods for verbal autopsy and mortality modeling, and has been a member of the WHO Verbal Autopsy Reference Group since 2013, contributing to the update of the WHO Standard Verbal Autopsy Instrument.

Research topics

• Medicine
• Environmental health
• Geography
• Virology
• Gerontology
• Internal medicine
• Immunology
• Pathology
• Demography
• Biology

Selected publications

• Young women's travel safety and the journey to work: Reflecting on lived experiences of precarious mobility in three African cities (and the potential for transformative action)

  Journal of Transport Geography · 2025-01-08 · 10 citations

  articleOpen access

  The relationship between women's everyday lived travel experiences as daily commuters and their employment history and potential has not been adequately researched and documented in African contexts. This multidisciplinary study, utilising an innovative action research methodology, compares experiences of young women (18-35y) resident in low-income neighbourhoods of three diverse African cities - Abuja, Cape Town and Tunis. It examines the challenges they face when undertaking travel to income-earning opportunities, the tactics necessary to enable travel with a modicum of safety and dignity, and the ongoing implications for women's employment trajectories and wider well-being. Two (often inter-related) themes occupy a central position in the discussion: mobility scheduling (as a response to domestic/care responsibilities and trip-chaining requirements) and experiences of harassment.

  PublisherDOI

• Write to return: Huguenot refugees on the frontiers of the French Enlightenment

  European Review of History Revue européenne d histoire · 2025-05-04 · 1 citations

  article1st authorCorresponding
  PublisherDOI

• ‘These Guys are Weird as Hell’: On the Democratic Party’s Use of ‘Weird’ During the 2024 US Presidential Election Campaign

  Political Communication · 2025-09-18

  articleOpen access1st authorCorresponding
  PublisherDOI

• Young men's daily mobility needs and practices in two low-income neighbourhoods of Cape Town: Reflections on first mile experiences, using an innovative community peer research methodology

  African Transport Studies · 2025-01-01 · 1 citations

  articleOpen access

  Understanding how young men navigate their journeys is important in the context of improving safe mobility for all, especially for those resident in city neighbourhoods with high rates of crime and poverty. Over the past decade, knowledge has been accumulating regarding the challenges faced by young women as they travel around urban areas across the African continent, but young men's lived mobility experiences have been largely ignored. This represents a major research gap. There often seems to be an (unwritten) assumption that men are invulnerable - free to travel wherever and whenever they choose - but there is a lack of specific knowledge of realities on the ground and how they impact on men's lives. In this paper we report recent research conducted with young men aged 18–35 years in two low-income neighbourhoods in Cape Town, utilizing a qualitative participatory Peer Research methodology. The focus is on understanding how young men resident in low-income areas experience and practice mobility, as they walk between home and local transport hubs (the ‘first mile’), wait at the hub, then journey onwards on motorised transport. Our findings suggest that while men's perceptions of potential danger do not necessarily stop them travelling, they experience moments of considerable stress in such contexts, such that they have to engage with a diversity of tactics to try to ensure a safe journey. There are potentially significant impacts on young men's well-being.

  PublisherDOI

• SVDMx: Child/Child-Adult Mortality-Indexed Model Mortality Age Schedules

  2025-02-07

  datasetOpen access1st authorCorresponding

  Model age schedules of mortality, nqx, suitable for a life table. This package implements the SVD-Comp mortality model indexed by either child or child/adult mortality. Given input value(s) of either 5q0 or (5q0, 45q15), the qx() function generates single-year 1qx or 5-year 5qx conditional age-specific probabilities of dying. See Clark (2016) &lt;<a href="https://doi.org/10.48550%2FarXiv.1612.01408" target="_top">doi:10.48550/arXiv.1612.01408</a>&gt; and Clark (2019) &lt;<a href="https://doi.org/10.1007%2Fs13524-019-00785-3" target="_top">doi:10.1007/s13524-019-00785-3</a>&gt;.

  PublisherOA PDFDOI

• Engaging citizens from low-income communities in transport planning: experiences from peer research studies conducted in three African cities

  Journal of Transport Geography · 2025-11-24

  articleOpen access

  This paper draws on experience from a series of transport-focused studies built round peer research with community members resident in low-income neighbourhoods at the periphery of three major cities: Abuja, Cape Town and Tunis. These were conducted firstly with young women aged 18–35 in all three cities over a four-year period (2019–2022, i.e. spanning the pandemic), followed by a recently completed pilot with young men in the same age group (but in this case restricted to Cape Town). The paper reflects firstly on the peer research methodology employed (including training procedures, ethical issues and context specific challenges/barriers) and the significant field outputs achieved by the groups concerned through their in-depth interviews, participant observation and mobility diaries. It then moves on to consider the engagement of the community peer researchers with city transport professionals and practitioners at our project stakeholder consultative group meetings and their potential for promoting the design of more inclusive, accessible and sustainable transport systems. While peer researchers' direct field evidence offers rare insights into the transport and mobility challenges that many marginalised residents of these low-income neighbourhoods experience in the everyday – perspectives that could be crucial to effective user engagement around transport issues in an Urban Living Lab - the actual patterns and potentialities of engagement within each city that might promote a more socially just travel environment are strongly shaped by a range of locally specific factors. These extend from resource and policy contexts set within distinctive local urban geographies, to the personalities and positionality of all actors involved.

  PublisherDOI

• Evaluating the performance of verbal autopsy for assigning cause of death in older adults: A population‐based cohort study in Karonga, Malawi

  Tropical Medicine & International Health · 2025-05-13

  articleOpen access

  BACKGROUND: Verbal autopsy, where a close caregiver or relative of someone who recently died reports on the signs, symptoms and circumstances preceding death, is useful for producing population-based cause of death estimates. However, the performance of verbal autopsy for older adult deaths is poorly understood. OBJECTIVES: To evaluate the performance of verbal autopsy in assigning cause of death for adults aged 50+ in a rural area of Malawi. METHODS: Cause of death was assigned to each death with a verbal autopsy in the Karonga Health and Demographic Surveillance site between 2002 and 2017 using two methods: (1) Physician review and (2) in silico verbal autopsy (a Bayesian probabilistic model). We calculated uncertainty in cause of death assignment for each method and calculated disagreement in cause of death between methods. Analyses were stratified by age group and sex. RESULTS: A total of 2378 adult deaths were included (1360 aged 50+). Cause of death assignment showed greater uncertainty at older ages in both methods. For example, 59.7% of men aged 80+ were assigned a specific cause of death using physician review, versus 77.5% of men aged 30-49. Population-level, broad cause of death distributions were similar across methods, but at the individual level there was over 30% disagreement on broad cause of death categories in those aged 50+. CONCLUSIONS: Verbal autopsy becomes more uncertain at assigning cause of death at older ages. The inclusion of any reports of medical diagnoses from a doctor and using a two-stage process of cause of death assignment (with simple cause of deaths assigned using algorithms and more complex cases being reviewed by physicians) could improve cause of death ascertainment using verbal autopsy at older ages.

  PublisherOA PDFDOI

• Temporal changes in cause of death among adolescents and adults in six countries in eastern and southern Africa in 1995–2019: a multi-country surveillance study of verbal autopsy data

  The Lancet Global Health · 2024-07-17 · 4 citations

  articleOpen accessSenior author

  BACKGROUND: The absence of high-quality comprehensive civil registration and vital statistics systems across many settings in Africa has led to little empirical data on causes of death in the region. We aimed to use verbal autopsy data to provide comparative, population-based estimates of cause-specific mortality among adolescents and adults in eastern and southern Africa. METHODS: In this surveillance study, we harmonised verbal autopsy and residency data from nine health and demographic surveillance system (HDSS) sites in Kenya, Malawi, Tanzania, South Africa, Uganda, and Zimbabwe, each with variable coverage from Jan 1, 1995, to Dec 31, 2019. We included all deaths to adolescents and adults aged 12 or over that were residents of the study sites and had a verbal autopsy conducted. InSilicoVA, a probabilistic model, was used to assign cause of death on the basis of the signs and symptoms reported in the verbal autopsy. Levels and trends in all-cause and cause-specific mortality rates and cause-specific mortality fractions were calculated, stratified by HDSS site, sex, age, and calendar periods. FINDINGS: 52 484 deaths and 5 157 802 person-years were reported among 1 071 913 individuals across the nine sites during the study period. 47 961 (91·4%) deaths had a verbal autopsy, of which 46 570 (97·1%) were assigned a cause of death. All-cause mortality generally decreased across the HDSS sites during this period, particularly for adults aged 20-59 years. In many of the HDSS sites, these decreases were driven by reductions in HIV and tuberculosis-related deaths. In 2010-14, the top causes of death were: road traffic accidents, HIV or tuberculosis, and meningitis or sepsis in adolescents (12-19 years); HIV or tuberculosis in adults aged 20-59 years; and neoplasms and cardiovascular disease in adults aged 60 years and older. There was greater between-HDSS and between-sex variation in causes of death for adolescents compared with adults. INTERPRETATION: This study shows progress in reducing mortality across eastern and southern Africa but also highlights age, sex, within-HDSS, and between-HDSS differences in causes of adolescent and adult deaths. These findings highlight the importance of detailed local data to inform health needs to ensure continued improvements in survival. FUNDING: National Institute of Child Health and Human Development of the US National Institutes of Health.

  PublisherOA PDFDOI

• Bayesian analysis of verbal autopsy data using factor models with age- and sex-dependent associations between symptoms

  arXiv (Cornell University) · 2024-03-18

  preprintOpen access

  Verbal autopsies (VAs) are extensively used to investigate the population-level distributions of deaths by cause in low-resource settings without well-organized vital statistics systems. Computer-based methods are often adopted to assign causes of death to deceased individuals based on the interview responses of their family members or caregivers. In this article, we develop a new Bayesian approach that extracts information about cause-of-death distributions from VA data considering the age- and sex-related variation in the associations between symptoms. Its performance is compared with that of existing approaches using gold-standard data from the Population Health Metrics Research Consortium. In addition, we compute the relevance of predictors to causes of death based on information-theoretic measures.

  PublisherOA PDFDOI

• Understanding Household Dynamics From the Ground Up: A Longitudinal Study From a Rural South African Setting

  Demography · 2024-01-11 · 3 citations

  articleOpen access

  Investigations into household structure in low- and middle-income countries (LMICs) provide important insight into how families manage domestic life in response to resource allocation and caregiving needs during periods of rapid sociopolitical and health-related challenges. Recent evidence on household structure in many LMICs contrasts with long-standing viewpoints of worldwide convergence to a Western nuclearized household model. Here, we adopt a household-centered theoretical and methodological framework to investigate longitudinal patterns and dynamics of household structure in a rural South African setting during a period of high AIDS-related mortality and socioeconomic change. Data come from the Agincourt Health and Socio-Demographic Surveillance System (2003-2015). Using latent transition models, we derived six distinct household types by examining conditional interdependency between household heads' characteristics, members' age composition, and migration status. More than half of households were characterized by their complex and multigenerational profiles, with considerable within-typology variation in household size and dependency structure. Transition analyses showed stability of household types under female headship, while higher proportions of nuclearized household types dissolved over time. Household dissolution was closely linked to prior mortality experiences-particularly, following death of a male head. Our findings highlight the need to better conceptualize and contextualize household changes across populations and over time.

  PublisherDOI

Recent grants

• NIH Grant K01HD057246

  NIH · $620k · 2013

• Verbal Autopsy: Reimagining Data & Automated Cause Assignment (using ALPHA Network data)

  NIH · $2.4M · 2016–2023

• NIH Grant R03AG028640

  NIH · $106k · 2008

Frequent coauthors

• Stephen Tollman

  Agincourt Health and Socio-Demographic Surveillance System

  248 shared

• Kathleen Kahn

  South African Medical Research Council

  232 shared

• Brian Houle

  201 shared

• Mark Collinson

  Agincourt Health and Socio-Demographic Surveillance System

  152 shared

• Chodziwadziwa Kabudula

  Agincourt Health and Socio-Demographic Surveillance System

  139 shared

• F. Xavier Gómez‐Olivé

  Indepth Network

  118 shared

• Nicole Angotti

  American University

  89 shared

• Enid Schatz

  University of Missouri

  86 shared