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Cited by 176HIV/AIDS Research and InterventionsHIV, Drug Use, Sexual RiskHealth disparities and outcomes

Syndemics and Health Disparities: A Methodological Note

Open access
Tsai, Alexander C., Venkataramani, Atheendar S.·2016·AIDS and Behavior
DOI 10.1007/s10461-015-1260-2PMC PMC4755906
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Abstract

In the theory of syndemics, diseases are hypothesized to co-occur in particular temporal or geographical contexts due to harmful social conditions (disease concentration) and to interact at the level of populations and individuals, with mutually enhancing deleterious consequences for HIV risk (disease interaction). Since its original elaboration more than 20 years ago, the epidemiological literature on syndemic problems has followed a questionable trajectory, stemming from the use of a specific type of regression model specification that conveys very little information about the theory of syndemics. In this essay we critically review the dominant approaches to modeling in the literature on syndemics; highlight the stringent assumptions implicit in these models; and describe some meaningful public health implications of the resulting analytical ambiguities. We conclude with specific recommendations for empirical work in this area moving forward.

AI snapshot

Written from the paper’s full text.

TL;DR

This methodological essay argues that common syndemics analyses using a summed count of psychosocial and structural problems cannot establish synergistic interaction, because a positive count coefficient can occur even under purely additive effects. It recommends using fully saturated interaction models to test syndemic theory and discusses implications for intervention design.

Key findings

  • In the systematic review cited (Tsai & Burns), 27 of 40 studies (68%) showed co-occurrence via Venn diagrams, correlation matrices, or odds ratio matrices, and 31 of 40 (78%) used a sum score of problems.
  • Algebraically, the sum-score coefficient can be positive and significant when the true data-generating process is additive; the sum score imposes equal effects across problems rather than testing synergy.
  • The saturated model with all product terms is the only specification that flexibly conveys interaction; the continuous sum-score model should be abandoned, and the ordinal sum-score model still assumes two-way product terms are zero.
  • Public health consequences include unclear excess concern for true syndemics, missed targeted intervention opportunities, and the multi-component “treatment package” not necessarily being optimal; alternatives include sequential, collateral, or fractional factorial strategies.

Methods

  • Critical methodological essay, not an empirical study; uses a hypothetical cohort of homeless and marginally housed women with violence, food insecurity, mental illness, and a binary HIV-related outcome.
  • Compares linear regression specifications: additive main-effects model, fully saturated interaction model, continuous sum score, and ordinal sum score; draws on a prior systematic review of 40 syndemics studies.
  • Main analysis is algebraic demonstration and discussion of assumptions, sample size/power, and recommendations.

Limitations

  • Stated: small samples may prevent full interaction estimation and yield wide confidence intervals; collinearity among co-occurring problems worsens imprecision; type II error may miss true syndemics or understate the number of interacting epidemics. Authors counter that nearly half of reviewed studies could fit saturated models by conventional rules.
  • Stated: sum-score specifications impose strong assumptions (e.g., equal main effects or zero two-way interactions) that are rarely justified by theory.
  • Evident from text: no new data are analyzed; the illustration is hypothetical and the critique relies on prior review and selected examples, so the recommendations are not empirically validated here.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1007/s10461-015-1260-2

Cites

65 of 65 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 27 cited sources checked · 0 supported · 0 flagged

  • Premisecitation

    Most studies conducted with the expressed aim of generating empirical support for the theory of syndemics have not operationalized the concept of disease interaction in a way that actually supports the theory's predictions about mutually enhancing epidemics.

    “Most studies that have been conducted with the expressed aim of generating empirical support for the theory of syndemics have not operationalized the concept of disease interaction in a way that actually supports the theory’s predictions about mutually enhancing epidemics [11].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [11] Tsai AC, Burns BFO. Syndemics of psychosocial problems and HIV risk: a systematic review of empirical tests of the disease interaction concept. Soc Sci Med. 2015;139(1):26–35. source

      Not checked in the free run.

  • Premisecitation

    Psychosocial and structural problems commonly and undoubtedly cluster among vulnerable populations.

    “While psychosocial and structural problems commonly and undoubtedly do cluster among vulnerable populations [5,6]”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [5] Farmer P, Lindenbaum S, Good MJ. Women, poverty and AIDS: an introduction. Cult Med Psychiatry. 1993;17(4):387–97. source

      Not checked in the free run.

    • cites [6] Farmer P. Women, poverty, and AIDS. In: Farmer P, Connors M, Simmons J, editors. Women, poverty and AIDS: sex, drugs, and structural violence. Monroe: Common Courage Press; 1996. p. 3–38.

      Not checked in the free run.

  • Interpretationreasoning

    Substituting for β2 and β3 in Eq. (1) shows that b8 does not provide evidence of synergy but rather simply encodes the assumptions that β1 = β2 = β3.

    “it becomes apparent that b8 does not provide evidence of synergy but rather simply encodes the assumptions that that β1 = β2 = β3.”
    Quote in the paperSubstantial claim
  • Interpretationnone given

    If b9 and b10 are estimated to be close to zero and b11 is positive and statistically significant, then the results obtained using Eq. (5) are identical to those that would be obtained using Eq. (2) when b1, b2, b3, b4, b5, and b6 are estimated to be close to zero, and b7 is positive and statistically significant.

    “It is worth noting that if b9 and b10 are estimated to be close to zero and b11 is positive and statistically significant, then the results obtained using Eq. (5) are identical to those that would be obtained using Eq. (2) when b1, b2, b3, b4, b5, and b6 are estimated to be close to zero, and b7 is positive and statistically significant.”
    Quote in the paperNot a substantial claim
  • Interpretationreasoning

    The sum score approach to modeling, which currently dominates the literature, does not generate estimates with clear programmatic implications for public health policy to address syndemics.

    “The sum score approach to modeling, which currently dominates the literature [11], does not generate estimates with clear programmatic implications for public health policy to address syndemics.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [11] Tsai AC, Burns BFO. Syndemics of psychosocial problems and HIV risk: a systematic review of empirical tests of the disease interaction concept. Soc Sci Med. 2015;139(1):26–35. source

      Not checked in the free run.

  • Classified as probably not a substantial claim. 20
  • May combine two claims. 15

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    In Singer's theory of syndemics, diseases are hypothesized to co-occur in particular temporal or geographical contexts due to harmful social conditions (disease concentration) and to interact at the level of populations and individuals, with mutually enhancing deleterious consequences for HIV risk (disease interaction).

    “In Singer’s [1–3] theory of syndemics, diseases are hypothesized to co-occur in particular temporal or geographical contexts due to harmful social conditions (disease concentration) and to interact at the level of populations and individuals, with mutually enhancing deleterious consequences for HIV risk (disease interaction).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [1] Singer M. AIDS and the health crisis of the U.S. urban poor; the perspective of critical medical anthropology. Soc Sci Med. 1994;39(7):931–48. source

      Not checked in the free run.

    • cites [2] Singer M. A dose of drugs, a touch of violence, a case of AIDS: conceptualizing the SAVA syndemic. Free Inq Creat Sociol. 1996;24(2):99–110.

      Not checked in the free run.

    • cites [3] Singer M. A dose of drugs, a touch of violence, a case of AIDS, part 2: further conceptualizing the SAVA syndemic. Free Inq Creat Sociol. 2006;34(1):39–53.

      Not checked in the free run.

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

    Interpretationnone given

    It remains unclear whether psychosocial and structural problems co-occur independently, whether they co-occur and are mutually enhancing, or whether they co-occur and are mutually causal.

    “it remains unclear whether they co-occur independently, whether they co-occur and are mutually enhancing (i.e., interact with each other), or whether they co-occur and are mutually causal (i.e., cause each other).”
    Quote in the paperNot a substantial claim

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

    Interpretationnone given

    Since its original elaboration more than 20 years ago, the epidemiological literature on syndemics has followed a problematic trajectory.

    “Since its original elaboration more than 20 years ago, the epidemiological literature on syndemics can best be characterized as following a problematic trajectory.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    Sum scores can help to demonstrate that being subjected to multiple psychosocial and structural problems is associated with adverse health outcomes, but not that they interact with each other to worsen health outcomes.

    “Stated simply, sum scores can help to demonstrate that being subjected to multiple psychosocial and structural problems is associated with adverse health outcomes -- not that they interact with each other to worsen health outcomes.”
    Quote in the paperSubstantial claim

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

    Interpretationreasoning

    Recommendations of this nature are rarely issued in the syndemics literature, perhaps owing to the empirical ambiguities described above.

    “Recommendations of this nature, however, are rarely issued in the syndemics literature, perhaps owing to the empirical ambiguities described above.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    While concerns about type II error are valid, they may be overstated.

    “While concerns about type II error are valid, they may be overstated.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationreasoning

    Failure to reject the null in a nested model test could support the use of the more restricted specification, while rejection of the null would speak to important differences in the lower-order product terms that are obfuscated in Eq. (5).

    “Failure to reject the null could support the use of the more restricted specification. However, rejection of the null would speak to important differences in the lower-order product terms that are obfuscated in Eq. (5), and researchers would still be provided with valuable information about the true underlying structure of the model.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    Analyses demonstrating co-occurrence of psychosocial and structural problems support one aspect of the theory of syndemics but do not necessarily implicate synergy or mutual causality.

    “Such analyses demonstrate that psychosocial and structural problems co-occur in at-risk populations -- thereby supporting one aspect of the theory of syndemics -- but do not necessarily implicate synergy or mutual causality.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Interpretationnone given

    Eq. (2) is the only specification that fully and flexibly conveys important information about how syndemic problems interact to worsen HIV risk.

    “If the primary analytic objective is to provide evidence of disease interaction, then Eq. (2) should be used, because it is the only specification that fully and flexibly conveys important information about how syndemic problems interact to worsen HIV risk.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    The sum score conveys very little information about the theory of syndemics: given a known data-generating process that explicitly excludes interactions, the estimated coefficient b8 on the sum score in Eq. (4) can nonetheless be positive and statistically significant.

    “To summarize, the sum score conveys very little information about the theory of syndemics: given a known data-generating process that explicitly excludes the possibility of interactions between the covariates, the estimated coefficient b8 on the sum score in Eq. (4) can nonetheless be positive and statistically significant.”
    Quote in the paperSubstantial claim

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

    Interpretationreasoning

    Even if valid concerns persist about statistical power to reject the null hypothesis for any specific regression coefficient, researchers could still estimate Eq. (2) while employing joint significance tests to determine whether some of the product terms are collectively important.

    “Third, even if valid concerns persist about statistical power to reject the null hypothesis for any specific regression coefficient, researchers could still estimate Eq. (2) while employing joint significance tests to determine whether some of the product terms are collectively important.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    The manner in which psychosocial and structural problems interact (or not) has implications for the types of interventions needed to reduce HIV risk, and whether these interventions necessarily need to be bundled to maximize their effectiveness.

    “The manner in which they interact (or not) has implications for the types of interventions needed to reduce HIV risk, and whether these interventions necessarily need to be bundled to maximize their effectiveness.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    Because the effects of co-occurring epidemics are simply additive in Eq. (1), Eq. (1) does not implicate a syndemic; all three epidemics need not be addressed jointly to reduce HIV risk.

    “Because the effects of these co-occurring epidemics are simply additive, Eq. (1) does not implicate a syndemic: all three epidemics need not be addressed jointly in order to reduce HIV risk.”
    Quote in the paperSubstantial claim

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

    Interpretationreasoning

    If syndemic problems actually do interact in ways that synergistically elevate HIV risk, but Eqs. (4) and (5) continue to dominate the literature, then the field is missing critical opportunities to identify these synergies and support the development of appropriately targeted interventions.

    “Second, if syndemic problems actually do interact in ways that synergistically elevate HIV risk, but Eqs. (4) and (5) continue to dominate the literature, then the field is missing critical opportunities to identify these synergies and support the development of appropriately targeted interventions.”
    Quote in the paperNot a substantial claim

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

    Premisecitation

    When b9, b10, and b11 are positive and statistically significant, and b11 > b10 > b9 in Eq. (5), this pattern is interpreted as evidence of "additive interplay" between psychosocial and structural problems that magnifies vulnerability to HIV risk.

    “When b9, b10, and b11 are positive and statistically significant, and b11 > b10 > b9, this pattern of estimates is also interpreted as evidence of “additive interplay” (p.941) between psychosocial and structural problems that magnifies vulnerability to HIV risk [30].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [30] Stall R, Mills TC, Williamson J, et al. Association of co-occurring psychosocial health problems and increased vulnerability to HIV/AIDS among urban men who have sex with men. Am J Public Health. 2003;93(6):939–42. source

      Not checked in the free run.

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

    Interpretationcitation

    Grouping some variables into broader clusters can reduce the number of parameters to be estimated in Eq. (2).

    “Second, researchers can group some of the variables into broader clusters (e.g., mental health, socioeconomic, etc) [32,63], especially for variables whose correlation approaches unity [64]. This maneuver can reduce the number of parameters to be estimated in Eq. (2).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [32] Sameroff AJ, Seifer R, Barocas R, Zax M, Greenspan S. Intelligence quotient scores of 4-year-old children: social-environmental risk factors. Pediatrics. 1987;79(3):343–50. source

      Not checked in the free run.

    • cites [63] Friedman EM, Montez JK, Sheehan CM, Guenewald TL, Seeman TE. Childhood adversities and adult cardiometabolic health: does the quantity, timing, and type of adversity matter? J Aging Health. 2015;27(8):1311–38. source

      Not checked in the free run.

    • cites [64] Arata CM, Langhinrichsen-Rohling J, Bowers D, O’Brien N. Differential correlates of multi-type maltreatment among urban youth. Child Abuse Negl. 2007;31(4):393–415. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    While b8 may provide important information about the effects of cumulative adversities, it does not provide information about synergistic interactions between these adversities.

    “A critical point of departure, however, is that while b8 may provide important information about the effects of cumulative adversities, it does not provide information about synergistic interactions between these adversities.”
    Quote in the paperSubstantial claim

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

    Interpretationreasoning

    Eq. (5) may, under certain conditions, provide more information than Eq. (4), but the strong assumptions required of the data suggest Eq. (2) is still to be preferred.

    “Eq. (5) may, under certain conditions, provide more information than Eq. (4), but the strong assumptions required of the data suggest Eq. (2) is still to be preferred.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationreasoning

    Eq. (4) cannot convey meaningful information about interactive effects and should be abandoned entirely in the literature on syndemics.

    “Eq. (4) cannot convey meaningful information about interactive effects and should be abandoned entirely in the literature on syndemics.”
    Quote in the paperSubstantial claim

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

    Interpretationcitation

    A close reading of Singer's work yields an understanding in which Eq. (2) should be regarded as the preferred approach to empirical modeling in the syndemics literature.

    “A close reading of Singer’s [1–3] work yields an understanding in which Eq. (2) should be regarded as the preferred approach to empirical modeling in this literature”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [1] Singer M. AIDS and the health crisis of the U.S. urban poor; the perspective of critical medical anthropology. Soc Sci Med. 1994;39(7):931–48. source

      Not checked in the free run.

    • cites [2] Singer M. A dose of drugs, a touch of violence, a case of AIDS: conceptualizing the SAVA syndemic. Free Inq Creat Sociol. 1996;24(2):99–110.

      Not checked in the free run.

    • cites [3] Singer M. A dose of drugs, a touch of violence, a case of AIDS, part 2: further conceptualizing the SAVA syndemic. Free Inq Creat Sociol. 2006;34(1):39–53.

      Not checked in the free run.

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

    Interpretationnone given

    With the strong assumption of no observed confounding, the linear regression model Eq. (1) estimates the causal relationship between psychosocial and structural problems and HIV risk.

    “With the strong assumption of no observed confounding, which is commonly and implicitly invoked in this literature, this regression model estimates the causal relationship between the psychosocial and structural problems and HIV risk.”
    Quote in the paperNot a substantial claim

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

    Interpretationnone given

    These linear restrictions simply encode the assumptions that already predominate in the syndemics literature but which should be formally motivated on the basis of conceptual considerations or previously published empirical work.

    “As is apparent in the equations above, these linear restrictions simply encode the assumptions that already predominate in the syndemics literature but which should be formally motivated on the basis of conceptual considerations or previously published empirical work.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    Singer's own work specifically excludes the sum score specification as an adequate test of his theory.

    “Moreover, his own work specifically excludes the sum score specification as an adequate test of his theory.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [39] Singer M, Clair S. Syndemics and public health: reconceptualizing disease in bio-social context. Med Anthropol Q. 2003;17(4):423–41. source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    The assumptions that β1 = β2 = β3 are unnecessary because they can be empirically proven or disproven using Eq. (1) to show that b1 = b2 = b3.

    “However, these assumptions are unnecessary because they can be empirically proven (or disproven) using Eq. (1) to show that b1 = b2 = b3.”
    Quote in the paperSubstantial claim

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

    Interpretationreasoning

    Demonstrating the joint statistical significance of a series of two- or three-way product terms could provide concrete evidence to motivate the need for studies with larger sample sizes.

    “Demonstrating the joint statistical significance of a series of two- or three-way product terms could provide concrete evidence to motivate the need for studies with larger sample sizes.”
    Quote in the paperNot a substantial claim

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

    Premisecitation

    As noted by Stall et al., small sample sizes may preclude full elucidation of all of the interaction effects in Eq. (2), potentially resulting in wide confidence intervals for the parameters of interest.

    “As noted by Stall et al. [55], small sample sizes may preclude full elucidation of all of the interaction effects in Eq. (2), potentially resulting in wide confidence intervals for the parameters of interest.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [55] Stall R, Coulter RWS, Friedman MR, Plankey MW. Commentary on “Syndemics of psychosocial problems and HIV risk: a systematic review of empirical tests of the disease interaction concept” by A. Tsai and B. Burns. Soc Sci Med. 2015;145(1):129–31. source

      Not checked in the free run.

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

    Premisecitation

    When b8 is positive and statistically significant in Eq. (4), the data are interpreted in the literature as demonstrating "interplay" between the psychosocial and structural problems.

    “When b8 is positive and statistically significant, the data are interpreted as demonstrating “interplay” (p.1269) between the psychosocial and structural problems [28].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [28] Biello KB, Colby D, Closson E, Mimiaga MJ. The syndemic condition of psychosocial problems and HIV risk among male sex workers in Ho Chi Minh City, Vietnam. AIDS Behav. 2014;18(7):1264–71. source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Interpretationnone given

    Eqs. (4) and (5) do not answer how much more undesirable a syndemic is compared to a scenario in which violence and food insecurity co-occur independently.

    “The answer to this question remains unanswered by Eqs. (4) and (5).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    Because the main effects are all null, public health interventions designed to eliminate the syndemic of X1, X2, and X3 are perfect complements, implying that no single intervention would be effective if implemented in isolation.

    “That is, because the main effects are all null, public health interventions designed to eliminate the syndemic of X1, X2, and X3 are perfect complements -- implying that no single intervention would be effective if implemented in isolation.”
    Quote in the paperSubstantial claim
29 of 29

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?

  • One commonly used specification in the literature encodes an assumption that epidemics A and B have no main effects and affect HIV jointly only when both are present.

    “Tsai and Venkataramani 19 showed, for example, that one of the most commonly employed specifications in the literature essentially encodes an assumption that epidemics A and B have null main effects and exert a joint effect on the HIV epidemic only when both A and B are present.”

    From Co-occurring epidemics, syndemics, and population health (2017) · cites this paper as [19]

    In “Dominant Approaches to Modeling in the Literature on Syndemics” (page unavailable), the paper says the commonly used sum-score specification encodes equal main effects, not null ones, and can produce a positive coefficient without any interaction. It says a different, categorical specification implies an effect only when all problems are present if its coefficients for one or two problems are estimated near zero; that is a conditional result, not an assumption encoded by the specification. (LLM, conf=0.86)

    Checked by a reasoning model — may be wrong.

    Experimental — accuracy not yet measured

  • The quantitative syndemics literature is increasingly discarding the uninformative language of additive associations.

    “while simultaneously becoming more accurate in its representations and increasingly discarding the uninformative19 language of “additive associations.””

    From Co-occurring epidemics, syndemics, and population health (2017) · cites this paper as [19]

    The Recommendations section (page unavailable) explicitly recommends modeling additive associations when that is the research objective; it calls the sum-score approach uninformative for detecting interactions, not the language of additive associations uninformative in general. The section on dominant modeling approaches says sum-score analyses appeared in 31 of 40 studies reviewed, rather than showing that the literature was increasingly discarding them. (LLM, conf=0.84)

    Checked by a reasoning model — may be wrong.

    Experimental — accuracy not yet measured

  • Conventional methods for testing models of synergistic disease interaction or multicomponent intervention effectiveness can face intractable difficulties because full factorial study designs are resource-demanding.

    “Unfortunately, use of conventional methods to test models of synergistic disease interaction or the effectiveness of multicomponent interventions can encounter intractable difficulties due to the resource demands of full factorial study designs (Tsai & Burns, 2015; Tsai & Venkataramani, 2016).”

    From Syndemics: a theory in search of data or data in search of a theory? (2018) · cites this paper as Tsai & Venkataramani, 2016

    In “The Public Health Case for Analytical Clarity” (page unavailable), the paper calls a full factorial randomized trial costly and proposes a fractional factorial approach for multicomponent interventions. In “Addressing Concerns about Sample Size” (page unavailable), it discusses difficulties estimating disease interactions, but does not attribute those difficulties to the resource demands of full factorial study designs or describe them as intractable. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • Researchers in the syndemics literature have not successfully accomplished what they set out to achieve.

    “Tsai and Burns (2015) and Tsai and Venkataramani (2016) demonstrated that researchers in this literature have not successfully accomplished what they set out to achieve”

    From Syndemic theory, methods, and data (2022) · cites this paper as Tsai and Venkataramani (2016)

    The Introduction says most studies aiming to support syndemics theory did not operationalize disease interaction in a way that supports its predictions. But the section “Modeling Interactions between Co-Occurring Psychosocial and Structural Problems” says studies demonstrated co-occurrence, supporting one aspect of the theory. The claim overgeneralizes this methodological criticism into a failure to achieve any research aim. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • The sum score does not illuminate either interaction or mutual causality.

    “While helpful, in some instances, for understanding the health effects of cumulative adversities, the sum score sheds light on the co-dynamics of neither interaction nor mutual causality.19”

    From Co-occurring epidemics, syndemics, and population health (2017) · cites this paper as [19]

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.

  • Category indicators do not sum to one for the reference group

    Minor

    For a person with zero problems, all three indicators are zero, so their sum is zero rather than one. The paper explicitly includes zero problems as the reference category.

1 of 1

Cites

Flagged first, then by citations

2 of the 67 references couldn’t be matched to a known paper.

Research works printed but not linked: 3

  1. Batchelder AB. Psychosocial syndemics of women living with and at-risk for HIV/AIDS (dissertation). New York: Yeshiva University; 2012.
  2. Ashenfelter O, Haveman RH, Riley JG, Taylor JT. Editorial statement. Am Econ Rev. 1986;76(4):v.
  3. Bernanke BS. Editorial statement. Am Econ Rev. 2004;94(1):404.

Cited by

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Related

Authors
Tsai, A. C., & Venkataramani, A. S.
Affiliations
Harvard University (US)
Corresponding author
Tsai, Alexander C.
ORCID
Venue
AIDS and Behavior
Publisher
Springer Science and Business Media LLC
Published
2015-12-12
Volume
20
Issue
2
Pages
423-430
ISSN
  • 1090-7165 (ISSN-L)
  • 1573-3254
DOI
10.1007/s10461-015-1260-2
PMC
PMC4755906
OpenAlex
W2191960283
Cited by
176
References
67
Citations by year
2026: 11 · 2025: 17 · 2024: 25 · 2023: 15 · 2022: 27 · 2021: 22 · 2020: 23 · 2019: 10 · 2018: 10 · 2017: 6 · 2016: 3
FWCI
4.90
Type
journal article
Language
en
Open access
Licence
Locations
  • AIDS and Behavior (publishedVersion)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (acceptedVersion)
  • PubMed Central (acceptedVersion)
Funders
National Institute of Mental Health (K23MH096620)
Topics
  • Health Sciences › Medicine › Infectious Diseases › HIV/AIDS Research and Interventions
  • Health Sciences › Medicine › Epidemiology › HIV, Drug Use, Sexual Risk
  • Social Sciences › Health › Health disparities and outcomes
Keywords
syndemic, health disparities, disease interaction, HIV risk, regression model specification, social conditions, epidemic modeling, public health implications
MeSH terms
Public Health, Regression Analysis, Social Environment, Social Problems, HIV Infections, Health Status Disparities

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