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Cited by 185HIV, Drug Use, Sexual RiskHomelessness and Social IssuesAdolescent Sexual and Reproductive Health

Syndemics: a theory in search of data or data in search of a theory?

Open access
Tsai, Alexander C.·2018·Social Science & Medicine
DOI 10.1016/j.socscimed.2018.03.040PMC PMC6613368
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Abstract

The concept of a syndemic was proposed more than two decades ago to explain how large-scale social forces might give rise to co-occurring epidemics that synergistically interact to undermine health in vulnerable populations. This conceptual instrument has the potential to help policymakers and program implementers in their endeavors to improve population health. Accordingly, it has become an increasingly popular heuristic for advocacy, most notably in the field of HIV treatment and prevention. However, most empirical studies purporting to validate the theory of syndemics actually do no such thing. Tomori et al. (2018) provide a novel case study from India illustrating how the dominant empirical approach fails to promote deeper understanding about how hazardous alcohol use, illicit drug use, depression, childhood sexual abuse, and intimate partner violence interact to worsen HIV risk among men who have sex with men. In this commentary, I relate the theory of syndemics to other established social science and public health theories of disease distribution, identify possible sources of conceptual and empirical confusion, and provide concrete suggestions for how to validate the theory using a mixed-methods approach. The hope is that more evidence can be mobilized -- whether informed by the theory of syndemics or not -- to improve health and psychosocial wellbeing among vulnerable populations worldwide.

Integrity signals

Registry

Crossref · 10.1016/j.socscimed.2018.03.040

Cites

92 of 92 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

31 of 63 cited sources checked · 18 supported · 0 flagged · accuracy not yet measured

  • Interpretationcitation

    The three models of co-occurring epidemics-mutually causal, synergistically interacting, and serially causal-generate starkly different predictions about the potential effectiveness of treatment or prevention strategies.

    “This practice contributes to ongoing confusion in the field because the three different models of co-occurring epidemics generate starkly different predictions about the potential effectiveness of treatment or prevention strategies.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Tsai et al., 2017 source

      In “Measuring syndemics” (page unavailable), the paper says that two models—mutual causality and synergistic interaction—imply different treatment or prevention strategies. The “Interpretation” passage explains how their predictions for single-component interventions differ. Our copy does not describe a third, serially causal model or compare its intervention predictions. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • Rests on an assumption: The three models of co-occurring epidemics—mutually causal, synergistically interacting, and serially causal—exhaust the possible interpretations of interaction in syndemic theory.
  • Premisecitation

    One of the most commonly used specifications of the sum score essentially encodes an assumption that a sufficient cause interaction exists.

    “Further, one of the most commonly used specifications of the sum score essentially encodes an assumption that there exists a sufficient cause interaction (Tsai et al., 2017).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Tsai et al., 2017 source
  • Interpretationcitation

    Except for detailed anthropological studies, the field has not found convincing empirical evidence supporting the disease interaction pillar of syndemic theory.

    “On the other hand, however, with the exception of detailed anthropological studies (Mendenhall, 2012, 2015; Mendenhall et al., 2012), the field has so far failed to find convincing empirical evidence to support the third pillar of the theory, i.e., disease interaction.”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites Mendenhall, 2012

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Mendenhall, 2015 source
    • cites Mendenhall et al., 2012 source
    • Rests on an assumption: The theory of syndemics has disease interaction as a necessary pillar.
  • Premisecitation

    Systematic reviews have shown that most epidemiological studies in the syndemics literature, all using individual-level data, have attempted to document syndemics with the sum score specification.

    “Systematic reviews have shown that most epidemiological studies in this literature -- all of which are based on individual-level data -- have attempted to document the existence of syndemics by using the “sum score” specification (Tsai & Burns, 2015; Tsai et al., 2017).”
    Quote in the paperSubstantial claim2 of 2 sources checked
    • cites Tsai & Burns, 2015 source

      The Results report that 31 of 40 reviewed studies (78%) used a sum score—the total count of psychosocial problems—to test the disease-interaction concept. The review concerns psychosocial problems and HIV risk; the passages do not establish that all epidemiological studies in the broader syndemics literature used individual-level data. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites Tsai et al., 2017 source
  • Premisecitation

    The sum score specification provides no information about the degree to which candidate health risks or epidemics interact, whether mutually causal, synergistically interacting, or serially causal.

    “It can be shown mathematically that the sum score specification conveys no information about the extent to which the candidate health risks interact (Tsai & Venkataramani, 2016).”
    • Also stated in: § The Tomori et al. (2018) study · plain
      “Put differently, the sum score specification conveys no information about the extent to which epidemics are mutually causal, synergistically interacting, or serially causal.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Tsai & Venkataramani, 2016 source
  • May combine two claims. 12
  • Classified as probably not a substantial claim. 25

  • May combine two claims.

    Premisecitation

    Agent-based models have been used to test interventions to enhance neighborhood collective efficacy to reduce racial and ethnic disparities in violent victimization and multicomponent interventions to improve diarrheal disease control.

    “enhancing neighborhood collective efficacy to reduce racial and ethnic disparities in violent victimization (Cerda et al., 2014), and multicomponent interventions to improve diarrheal disease control (Mellor et al., 2012)”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites Cerda et al., 2014 source
    • cites Mellor et al., 2012 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    Nodes with high out-strength could represent potential targets for intervention because they have a greater likelihood of influencing other nodes in the network.

    “Nodes with high levels of correlations with other nodes (out-strength) could represent potential targets for intervention, as Tomori et al. (2018) usefully suggest, given that they have a greater likelihood of influencing other nodes in the network.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Tomori et al. (2018) source

      The Discussion (page unavailable) suggests targeting antecedent adverse conditions to prevent a cascade and selecting interventions for the greatest effect on sexual risk. It does not discuss network nodes, out-strength, or whether highly correlated nodes are more likely to influence other nodes. (LLM, conf=0.79)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Agent-based models have been used to test the effectiveness of stigmatization and social network targeting strategies for obesity and structural interventions to increase fresh produce consumption among low-income households.

    “Agent-based models have been used, for example, to test the effectiveness of stigmatization and social network targeting strategies in addressing the obesity epidemic (Zhang et al., 2015), structural interventions to increase consumption of fresh produce among low-income households (Widener, Metcalf, & Bar-Yam, 2013)”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Zhang et al., 2015 source
    • cites Widener, Metcalf, & Bar-Yam, 2013 source

  • May combine two claims.

    Premisecitation

    In the Tomori et al. study, fewer than 15 percent of the sample reported two or more health risks, so it did not appear that many health risks were co-occurring.

    “Nor did it appear that many of the health risks were co-occurring, as fewer than 15 percent of the sample reported two or more health risks.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Tomori et al. (2018) source
    • Rests on an assumption: Health risks are not meaningfully co-occurring when fewer than 15 percent of a sample reports two or more of them.

  • May combine two claims.

    Premisecitation

    Out of 26 two- and three-way interactions tested for two outcomes, Tomori et al. found evidence of synergy only between intimate partner violence and depression for condomless anal intercourse, and between hazardous alcohol use and illicit drug use for active syphilis.

    “Out of 26 two- and three-way interactions tested for the two outcomes, they found evidence of synergy only between intimate partner violence and depression for the outcome of condomless anal intercourse, and between hazardous alcohol use and illicit drug use for the outcome of active syphilis.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Tomori et al. (2018) source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Blakely and Woodward described three principal mechanisms through which ecological constructs can affect individual-level outcomes: cross-level effect modification, direct cross-level effects, and indirect cross-level effects.

    “Blakely and Woodward (2000) described three principal mechanisms through which ecological constructs can affect individual-level outcomes: cross-level effect modification (e.g. the association between men’s beliefs about gender roles and women’s experience of intimate partner violence is modified by laws disadvantaging women relative to men in their access to resources and factors of production),”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Blakely and Woodward (2000) source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Tomori et al. (2018) offer a novel investigation into hazardous alcohol use, illicit drug use, depression, childhood sexual abuse, and intimate partner violence among men who have sex with men.

    “It is in this context that Tomori et al. (2018) offer a novel investigation into the epidemics of hazardous alcohol use, illicit drug use, depression, childhood sexual abuse, and intimate partner violence among men who have sex with men.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Tomori et al. (2018) source

      The Methods (Syndemic Conditions) and Results show that Tomori et al. investigated illicit drug use, depression, childhood sexual abuse, intimate partner violence, and alcohol use among men who have sex with men in India. The paper specifically measured alcohol dependence (AUDIT score ≥15), not hazardous alcohol use as stated in the claim. (LLM, conf=0.84)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Social network analysis has been increasingly used to illustrate psychiatric disorders as causal systems or to clarify the role of symptom overlap in characterizing constellations of psychiatric disorders.

    “Social network analysis has been increasingly used to illustrate psychiatric disorders as causal systems (McNally et al., 2015) or to clarify the role of symptom overlap in characterizing constellations of psychiatric disorders (Bekhuis et al., 2016; Bringmann et al., 2015).”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites McNally et al., 2015 source
    • cites Bekhuis et al., 2016 source
    • cites Bringmann et al., 2015 source

      The Community structure analysis (p. 5) and Discussion (p. 9) show that the paper uses a symptom network to identify clusters within depression. They do not establish a role for symptom overlap in characterizing constellations of different psychiatric disorders; the analysis concerns BDI-II depression symptoms. (LLM, conf=0.82)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    In the Tomori et al. study, the prevalence of illicit drug use during the 6 months before interview was less than 3 percent, so not all studied health risks would be considered epidemic.

    “Not all the studied health risks would be considered “epidemic,” as the prevalence of illicit drug use during the 6 months prior to interview was less than 3 percent.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Tomori et al. (2018) source
    • Rests on an assumption: A health risk with prevalence below 3 percent should not be considered an epidemic.

  • May combine two claims.

    Premisecitation

    Tomori et al. found a statistically significant association between the sum score and condomless anal intercourse, as have most studies in this literature.

    “They found, as have most studies in this literature, a statistically significant association between the sum score and the outcome of condomless anal intercourse.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Tomori et al. (2018) source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The serially causal epidemics model is based on theories about the adverse consequences of accumulating and/or serially causal health risks.

    “Serially causal epidemics: This category represents a somewhat heterogeneous group of models that are based on well-known theories about the potential adverse consequences of accumulating and/or serially causal health risks.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Riley, 1989

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Geronimus, 1992
    • cites McEwen & Stellar, 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The structural aspect of the theory of syndemics follows theories of disease distribution, which highlight large-scale forces driving concentrated health disadvantage at the population level.

    “The structural aspect of his theory follows in the vein of what Krieger (2000) describes as “theories of disease distribution” (p.160), all of which have highlighted the role of large-scale forces in driving concentrated health disadvantage at the population level.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Krieger (2000) source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Singer initially portrayed the SAVA syndemic as a triangle and discussed substance abuse, violence, and HIV as mutually causal.

    “Singer (1996) initially portrayed the SAVA syndemic diagrammatically as a triangle. The discussion in his initial treatise focuses on the manifold ways in which the three epidemics are thought to be mutually causal: substance abuse is a risk factor for violent victimization and/or HIV acquisition, victimization may lead to substance abuse and/or HIV acquisition, and people with HIV are at greater”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Singer (1996)

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    In other elaborations of syndemic theory, the framing uses interaction or synergism, where synergy means that disease burden from joint health risks exceeds the sum of the disease burdens of the risks in isolation.

    “Synergistically interacting epidemics: In other elaborations of the theory of syndemics, the framing adopts the language of interaction or synergism. Synergy implies that the disease burden attributable to joint health risks exceeds the sum of the disease burden of the health risks in isolation (Rothman, 1974).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Rothman, 1974 source

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    The mutually causal epidemics model implies that addressing all epidemics or health risks may be necessary to effectively reduce disease burden.

    “The model of mutually causal epidemics implies that addressing all epidemics or health risks may be necessary to effectively reduce the burden of disease (or that, in a single population with multiple epidemics, addressing all epidemics would be needed to achieve as much disease burden reduction as addressing the equivalent number of single epidemics present in separate populations).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S4 (based).

    Interpretationnone given

    Confusion over how to operationalize syndemics in empirical work may arise from imprecision in how the theory of syndemics has been described.

    “Possibly the confusion over how to operationalize syndemics in the empirical literature stems from imprecision in how the theory of syndemics has been described (Fig. 2).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The theory of syndemics was first proposed by Singer in 1996 to describe synergistically related epidemics that cluster and arise from harmful social conditions.

    “The theory of syndemics was first proposed by Singer (1996) to describe “synergistically related” (p.103) epidemics that cluster and arise from harmful social conditions.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Singer (1996)

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    The complex, multifactorial processes that characterize syndemics may be well suited for study with agent-based models.

    “The complex, multifactorial processes that outline the contours of syndemics may be well suited to applications of agent-based models.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: Syndemics are complex, multilevel phenomena.

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationreasoning

    The synergistically interacting epidemics model potentially implies that one epidemic or health risk can be addressed in isolation while leaving the other intact, and that doing so should yield a greater reduction in disease burden than if no interactions were present.

    “In contrast, the model of synergistically interacting epidemics potentially implies that one epidemic or health risk can be addressed in isolation while leaving the other intact, and that doing so should be expected to result in a greater reduction in disease burden than otherwise would be expected if no interactions were present.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    Syndemics are theorized to be multilevel phenomena in which epidemics interact at both population and individual levels.

    “Third, syndemics are theorized to be multilevel phenomena in which epidemics interact at both the level of populations and the level of individuals (Singer, 2006).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Singer, 2006

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Interpretationreasoning

    The suggestion that redefining syndemics could spur greater integration of quantitative and qualitative methodologies does not necessarily follow from that suggestion.

    “Fourth, while the authors suggest that redefining syndemics could spur “greater integration of quantitative and qualitative methodologies,” such an outcome does not necessarily follow from the suggestion.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    Redefining the concept of a syndemic strictly on the basis of individual-level analyses would not necessarily support expanding such a reconceptualization to the population level.

    “Redefining the concept of a syndemic strictly on the basis of individual-level analyses would not necessarily support expanding such a reconceptualization to the population level.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Interpretationnone given

    More qualitative data can be brought to bear on the study of syndemics without accommodating the sum score approach.

    “More qualitative data can be brought to bear on the study of syndemics without accommodating the sum score approach (as is described in more detail below).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Path analysis is a form of structural equation modeling that can be used to examine both direct and indirect hypothesized associations between several different variables.

    “Path analysis is a form of structural equation modeling that can be used to examine both direct and indirect hypothesized associations between several different variables (Wright, 1920, 1921).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Wright, 1920, 1921

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    In the context of a longitudinal study, social network analysis could be used to elucidate the processes through which nodes interact with each other and exert potentially reinforcing effects.

    “In the context of a longitudinal study, this type of analysis could be used to elucidate the processes through which the nodes interact with each other and exert potentially reinforcing effects.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    Empirical studies of syndemics are natural candidates for multilevel models, which bridge ecological and individual-level data and permit simultaneous estimation of associations at different levels.

    “One would expect empirical studies of syndemics to be natural candidates for the application of multilevel models, which bridge analyses of ecological and individual-level data and permit simultaneous estimation of associations at different levels (Diez-Roux, 1998; Duncan, Jones, & Moon, 1998).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Diez-Roux, 1998 source
    • cites Duncan, Jones, & Moon, 1998 source

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    Failure to explicitly model the colluding social forces responsible for syndemic health risks leads the field away from political, economic, and cultural explanations of concentrated health disadvantage and toward disembodied notions of comorbidity.

    “Failure to explicitly model the colluding social forces responsible for syndemic health risks leads the field away from political, economic, and cultural explanations of concentrated health disadvantage and toward disembodied notions of comorbidity.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    In contrast to path analysis, network analysis does not rely on an a priori specified model relating nodes to each other; rather, the strength of linkages and the centrality of certain nodes emerge from the analysis.

    “In contrast to path analysis, network analysis does not rely on an a priori specified model relating the nodes to each other; rather, the strength of the linkages (edges) and the centrality of certain nodes emerges from the analysis.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Cramer et al., 2010 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    Building an agent-based model of syndemics would require analysts to specify their assumptions about how syndemics operate.

    “Importantly, the process of model construction would require analysts to make concrete their (presumably theory-based) assumptions about how they expect syndemics to operate.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    There is a danger that haphazard expansion of the syndemic concept will produce predictions so diffuse that the theory becomes useless.

    “There is a danger that the haphazardly expanding concept of a syndemic will generate predictions so diffuse that the theory is rendered useless.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable). May combine two claims.

    Interpretationreasoning

    Anthropologists can develop concepts in the field, use them to build an agent-based model, and test their social theories by checking whether emergent phenomena match field observations.

    “More generally, anthropologists can develop concepts in the field, use the concepts to construct an agent-based model, and then test the consistency of their social theories by assessing the extent to which the emergent phenomena match their field observations.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S4 (based).

    Interpretationnone given

    The theory of syndemics has the potential to help policymakers and program implementers improve population health.

    “The theory of syndemics has the potential to help policymakers and program implementers in their endeavors to improve population health.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: Syndemics are complex, multilevel phenomena.

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Interpretationreasoning

    Agent-based models can suggest new questions for fieldwork and thereby improve ongoing anthropological research.

    “Agent-based models can also suggest new questions for the fieldwork, thereby improving ongoing anthropological research.”
    Quote in the paperNot a substantial claim
33 of 33

  • The paper relies on this without support.

    A health risk with prevalence below 3 percent should not be considered an epidemic.

    “Not all the studied health risks would be considered “epidemic,” as the prevalence of illicit drug use during the 6 months prior to interview was less than 3 percent.”

  • The paper relies on this without support.

    Health risks are not meaningfully co-occurring when fewer than 15 percent of a sample reports two or more of them.

    “Nor did it appear that many of the health risks were co-occurring, as fewer than 15 percent of the sample reported two or more health risks.”

  • The paper relies on this without support.

    The three models of co-occurring epidemics—mutually causal, synergistically interacting, and serially causal—exhaust the possible interpretations of interaction in syndemic theory.

    “One might anticipate the argument that the word “interaction” could be consistent with several different models of relating co-occurring epidemics to each other: Mutually causal epidemics:”

  • The paper relies on this without support.

    The theory of syndemics has disease interaction as a necessary pillar.

    “the field has so far failed to find convincing empirical evidence to support the third pillar of the theory, i.e., disease interaction.”

  • The paper relies on this without support.

    There are few relevant examples in the literature of agent-based modeling applied to syndemics.

    “Relevant examples of agent-based modeling of syndemics are scarce in the literature.”

  • The paper relies on this without support.

    Syndemics are complex, multilevel phenomena.

    “As theorized, syndemics are complex, multilevel phenomena”
6 of 6

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Tsai (2018) distilled current scholarship on syndemics into a simple typology: synergistically interacting epidemics, mutually causal epidemics, serially causal epidemics, and the 'cumulative adversity' model.

    “Tsai (2018) distilled current scholarship on syndemics into a simple typology.”

    From Syndemic theory, methods, and data (2022) · cites this paper as Tsai (2018)

    In the Introduction section “How do epidemics ‘interact’?”, Tsai distinguishes three models: mutually causal, synergistically interacting, and serially causal epidemics. The quoted expansion adds cumulative adversity as a fourth model, but the “Tomori et al. (2018) study” section contrasts cumulative adversities with syndemics rather than including them in that typology. The verbatim citing sentence’s narrower claim that Tsai presents a typology is supported. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • Most empirical studies purporting to validate syndemic theory do not actually validate it.

    “most empirical studies purporting to validate the theory actually do no such thing.”

    From Recommendations for empirical syndemics analyses: A stepwise methodological guide (2024) · cites this paper as [15]

  • The extent to which the evidence is consistent with a syndemic is contingent upon how a syndemic is conceptualised.

    “Our study demonstrates that the extent to which the evidence is consistent with a syndemic is contingent upon how a syndemic is conceptualised (Tsai, 2018).”

    From The syndemic of violence victimisation, drug use, frequent alcohol use, and HIV transmission risk behaviour among men who have sex with men: Cross-sectional, population-based study in India (2019) · cites this paper as Tsai, 2018

  • Tsai (2018) provided a typology of three potential ways of conceptualising co-occurring epidemics: mutually causal and synergistically interacting epidemics, and serially causal epidemics.

    “Drawing on these theories, Tsai (2018) provided a typology of three potential ways of conceptualising co-occurring epidemics: mutually causal and synergistically interacting epidemics, which are statistically distinct ways of understanding co-occurring epidemics (Rothman, Greenland, & Walker, 1980) but which are often used interchangeably in the literature on syndemics (Singer, 1996, Singer and”

    From The syndemic of violence victimisation, drug use, frequent alcohol use, and HIV transmission risk behaviour among men who have sex with men: Cross-sectional, population-based study in India (2019) · cites this paper as Tsai (2018)

  • Tsai (2018) describes three syndemic models: synergistically interacting, mutually causal, and serially causal.

    “Tsai (2018) posits three models of syndemics: they can be “synergistically interacting”, which means the interaction between conditions amplifies health burdens (Singer & Clair, 2003); they can be “mutually causal”, which means each condition simultaneously influences the nature of the other (Singer, 2006); they can also be “serially causal”, where the effects of one condition snowballs into other”

    From Gendered syndemic of intimate partner violence, alcohol misuse, and HIV risk among peri-urban, heterosexual men in South Africa (2022) · cites this paper as Tsai, 2018

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Wang citation year differs from the reference list

    Minor

    The text cites Wang et al. as a 2018 work, but the corresponding reference lists it as 2017.

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Authors
Tsai, A. C.
Affiliations
Harvard University (US)
Corresponding author
Tsai, Alexander C.
ORCID
Tsai, Alexander C.
Venue
Social Science & Medicine
Publisher
Elsevier BV
Published
2018-06
Volume
206
Pages
117-122
ISSN
0277-9536 (ISSN-L)
DOI
10.1016/j.socscimed.2018.03.040
PMC
PMC6613368
OpenAlex
W2794984501
Cited by
185
References
88
Citations by year
2026: 21 · 2025: 27 · 2024: 18 · 2023: 22 · 2022: 26 · 2021: 25 · 2020: 23 · 2019: 12 · 2018: 5
FWCI
10.23
Type
journal article
Language
en
Open access
Licence
www.elsevier.com/tdm/userlicense/1.0/ (tdm)
Locations
  • Social Science & Medicine (publishedVersion)
  • PubMed (publishedVersion)
  • PubMed Central (submittedVersion)
Topics
  • Health Sciences › Medicine › Epidemiology › HIV, Drug Use, Sexual Risk
  • Health Sciences › Health Professions › General Health Professions › Homelessness and Social Issues
  • Health Sciences › Health Professions › General Health Professions › Adolescent Sexual and Reproductive Health
Keywords
syndemic, HIV risk, men who have sex with men, hazardous drinking, illicit drug use, depression, child sexual abuse, intimate partner violence
MeSH terms
Humans, Global Health, Comorbidity, Vulnerable Populations, Epidemics, Social Theory

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Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-05.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-05.

Cited sources are checked by gpt-6-sol.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

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