AIFS staff presentation

Philadelphia USA, 13 July 2011
19th American Professional Society on the Abuse of Children (APSAC) Colloquium, Pre-Conference Cultural Institute

What’s the use of the ‘multi-type maltreatment’ and ‘polyvictimisation’ concepts? International comparison of key issues, predictors, prevalence and the impact on wellbeing

Dr Daryl Higgins
Deputy Director (Research), Australian Institute of Family Studies

Rhys Price-Robertson
Senior Research Officer, Australian Institute of Family Studies

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Slide outline

  1. What’s the use of the ‘multi-type maltreatment’ and ‘polyvictimization’ concepts? International comparisons of key issues, predictors, prevalence, and the impact on wellbeing

    Daryl Higgins Deputy Director (Research), Australian Institute of Family Studies
    & Rhys Price-Robertson (Senior Research Officer, AIFS)

    Presentation at the APSAC 19th Annual National Colloquium
    Philadelphia, PA, USA 13-16 July 2011
  2. Acknowledgement

    Thanks to AIFS colleagues who assisted with analysis of data from the Australian Temperament Project:
    • Rhys Price-Robertson
    • Suzanne Vassallo
    • Rhys Price-Robertson also assisted with searching and reviewing the international literature.
    • Disclaimer: The Australian Institute of Family Studies (AIFS) is committed to the creation and dissemination of research-based information on family functioning and wellbeing. Views expressed here are those of individual authors and may not reflect those of the Australian Institute of Family Studies or the Australian Government.
  3. Presentation Outline
    • Background
    • Overview of the two key concepts:
      • Multi-type maltreatment
      • Poly-victimization
    • Retrospective data on maltreatment and bullying from the Australian Temperament Project
    • Key messages about child maltreatment and victimization
  4. Background
    • Types of abuse and neglect
      • Physical abuse
      • Sexual abuse
      • Neglect
      • Emotional or psychological abuse
      • Witnessing family violence
    • Continuum from low to high severity
    • Different types frequently co-occur
    • Typically not a single incident – often reflecting a pattern of poor parenting
  5. History of child maltreatment research
    • Modern child protection initiatives and research have focused on:
      • Physical abuse – Kempe et al., 1962 “battered-child syndrome”
      • Physical neglect
      • Late 1970s and 1980s: focus on sexual abuse
        • Specific attention paid to trying to find sexual abuse-specific sequelae ( ‘indicators’)
      • 1990s: attention paid to emotional abuse and neglect
      • Late 1990s and 2000s:
        • more direct attention paid to the impact on children of exposure to parental violence
        • understanding the interrelationship between different maltreatment types
  6. Multi-type maltreatment – the concept
    • Coined by Higgins & McCabe (1998, 2000) in Australia
    • Developed as an explanatory tool to account for:
      • the overlap in occurrence of the five types of child maltreatment (physical, sexual, psychological, neglect, & witnessing family violence)
      • variability in short- & long-term psychological adjustment of children and adults who have experienced various forms of child abuse and neglect
    • Began as a way of understanding the outcomes of sexual abuse
      • by the mid-1990s: the hope for sexual-abuse specific symptoms was not being realised
      • researchers were starting to focus on family dysfunction as a way of accounting for the effects of sexual abuse
      • required a thorough measure of other abusive/neglectful family experiences (i.e., what is it about dysfunctional families that is harmful?)
  7. Multi-type maltreatment (cont.)
    • Theoretical basis:
    • Integrated risk-sequelae model
    • Published in Journal of Sex Research (Higgins & McCabe, 1994)
    • Provided a theoretical model and empirical support for a variety of factors that are associated with the ‘risk’ of sexual abuse occurrence contributing independently to the variety of psychological problems previously associated directly with sexual abuse ( depression, anxiety, sleep disturbance, trauma symptomology, etc. ) i.e., a model that integrated risk factors for sexual abuse with the outcomes (“sequelae”)
    • Development of a measure for the 5 types of maltreatment using continuous scales: Comprehensive Child Maltreatment Scales
  8. Comprehensive Child Maltreatment Scales (CCMS)
    • Published in Journal of Family Studies (Higgins & McCabe, 2001)
    • Two versions for adults (CCMS-A: retrospective reports of their childhood experiences) and parents (CCMS-P: for reporting on experiences of their children aged 5-12)
    • Valid and reliable
      • Concurrent criterion-related validity with relevant subscales from the Child Abuse Trauma Scale : home atmosphere; punishment; sexual abuse (Saunders & Becker-Lausen, 1995)
      • Adequate test-retest reliability (CCMS-A: r = .92; CCMS-P: r = .93) & internal consistency (CCMS-A a= .93; CCMS-P a= .96)
    • Largely small-to-moderate sized, non-clinical samples; primarily research from Australia; though a growing international base, and some clinical research (Buckle et al., 2005)
  9. Multi-type maltreatment (cont.)
    • Empirical support:
    • systematic review of 29 studies using retrospective report from adults, where more than one type of child abuse or neglect was measured ( Higgins & McCabe 2001)
      • Often no outcome measure, so relationships between particular subtypes – or patterns of overlapping subtypes (i.e., multi-type maltreatment) – and particular outcomes were not being assessed.
      • Not all 5 types were routinely measured – many researchers only examined 2 or 3 types. Our earlier study (Higgins & McCabe 2000) was the only one where all five were examined.
      • Principal focus was on sexual abuse, followed by physical abuse.
  10. Multi-type maltreatment (cont.)
    • These early studies of multi-type maltreatment showed:
    • A large proportion of adults who experienced maltreatment in childhood were subjected to more than one form of abuse and neglect.
    • These adults demonstrate significantly greater difficulties in their lives ( “psychological adjustment problems”) than adults reporting a single form of abuse or neglect, or those reporting none.
    • Actual percentages of adults who have experienced multi-type maltreatment could not be reliably calculated because of lack of consistent definition, exclusion of some forms of maltreatment (particularly exposure to family violence).
    • Despite a call more than 5 years earlier for researchers to examine the effects of multiple forms of maltreatment (Kinard, 1994), little advancement had been made in the following 5-6 years.
  11. Predictors of multi-type maltreatment
    • Common family factors associated with experiences of multi-type maltreatment:
      • low family cohesion
      • low family adaptability
      • poor quality inter-parental relationships
      • poor quality childhood relationships
      • traditional parental family values
      • parental sexual punitiveness
  12. Key message from review of early multi-type maltreatment studies:
    • “ Studies in which multiple forms of child maltreatment are assessed are likely to provide a more accurate picture of the adjustment problems associated with each type of abuse and neglect.
    • “ However, unless other maltreatment types are also assessed, it should not be presumed that “effects” are specific to the particular type of maltreatment assessed on its own.” ( Higgins & McCabe, 2001, p. 567)
  13. Key findings from early multi-type maltreatment studies
    • Significant overlap in the occurrence of all types of child abuse and neglect, ranging from:
      • r = .24 (sexual abuse & witnessing family violence) to
      • r = .74 (physical abuse and psychological maltreatment)
    • When using an arbitrary cut-off (mean), those with high scores on 2 maltreatment types had poorer outcomes than those with only a single type; those with 3 or more types scored even worse
  14. Is differentiating between maltreatment subtypes helpful in explaining outcomes?
    • Results from an analysis of parent-report and adult self-report data suggest that the degree (frequency and severity) to which young people experience a range of abusive/neglectful behaviours is more important than the particular sub-type of maltreatment in explaining subsequent psychological problems (Higgins, 2004) .
  15. Studies of all 5 types of maltreatment

    Authors Year n Rate Key outcomes
    McGee, Wolfe & Wilson 1997 160   Internalising & externalising behaviours
    Higgins & McCabe 1998 50 42% Internalising & externalising behaviours
    Higgins & McCabe 2000 175 43.4% Trauma symptoms, depression, self-esteem
    Higgins & McCabe 2001 413    
    Stevens & Higgins 2002 44 50% Trauma symptoms, but not worker burnout
    Bevan & Higgins 2002 36   Spouse abuse
    Higgins 2003 133 43.6% Depression
    Higgins & McCabe 2003 283   Trauma symptoms; sexual behaviour probs
    Dong, Anda, Felitti et al. 2004 8,629    
    Sesar, Zivcic-Becirevic & Sesar 2008 458 57%  
    Vranceanu, Hobfoll & Johnson 2007 100   Stress, PTSD symptoms, social support
  16. Poly-victimization – the concept
    • Coined Finkelhor and colleagues in the US
    • Developed as an explanatory tool to account for:
      • the overlap in occurrence of parental abuse and neglect – and other forms of youth victimization (bullying, assault, etc.)
      • variability in short- & long-term psychological adjustment of children and adults who have experienced various forms of victimisation
    • Key focus
      • Conceptual basis: developmental victimology (Finkelhor, 2008)
      • Explains how different types of victimization relate to one another, how young people may be more vulnerable to particular type(s) of harm due to their age, and how impacts may change over time
  17. Poly-victimization – the concept (cont.)
    • Finklehor, Hamby and colleagues developed the Juvenile Victimization Questionnaire (JVQ), in an attempt to fill the gap among existing instruments, which tend to look at only a limited range of victimization types
    • JVQ measures 34 different forms of victimization, which fall into four broad categories:
      • violent and property crimes (e.g., assault, burglary)
      • child welfare violations (e.g., neglect, emotional abuse)
      • the violence of warfare and civil disturbances
      • Bullying
    • JVQ standard version – incidence in past 12 months
    • alternate version of JVQ measures prevalence, but rarely used
  18. Poly-victimization – the evidence
    • Poly-victimization common: 22% of children experienced 4+ kinds of victimization in the past year
    • Finklehor & colleagues demonstrated that it is the cumulative harm of multiple victimization experiences that is most predictive of trauma symptoms:
      • “Poly-victimization was highly predictive of trauma symptoms, and when taken into account, greatly reduced or eliminated the association between individual victimizations (e.g., sexual abuse) and symptomatology.”
      • Finkelhor, Ormrod & Turner (2007, p. 7)
  19. Poly-victimization studies

    Authors Year n Rate Key outcomes
    Finkelhor, Ormrod, Turner & Hamby 2005 2030 22% Trauma symptoms
    Finkelhor, Ormrod, & Turner 2007 2030 22% Trauma symptoms
    Finkelhor, Ormrod, & Turner 2007 1467 18% Trauma symptoms
    Finkelhor, Ormrod, & Turner 2007 1467   Risk of re-victimization
    Turner, Finkelhor, & Ormrod 2007 1009 20% Use of counselling services
    Cuevas, Finkelhor, Ormrod, & Turner 2009 2030   Psychiatric disorders
    Finkelhor, Ormrod, & Turner 2009 1467 Prev Trauma symptoms
    Finkelhor, Ormrod, Turner, & Hol 2009 989 24%  
    Elliott, Alexander, Pierce, Aspelmeier & Richmond 2009 329 Prev College adjustment
    Ford, Elhai, Connor, & Frueh 2010 3351   Psychiatric problems; delinquency
    Hamby, Finkelhor, Turner, & Ormrod 2010 4549   Witnessing partner violence
    Turner, Finkelhor, & Ormrod 2010 4053 30% Trauma symptoms
  20. Summary: multi-type maltreatment and poly-victimization
    • Multi-type maltreatment
      • comprehensive coverage of child abuse and neglect, but does not include other forms of child victimization
      • focuses on lifetime prevalence (retrospective; or parent-reports)
      • accounts for severity of maltreatment types
      • detailed measurement of small set of victimization types
    • Poly-victimization
      • to date: mostly measured on incidence basis – not easy to convert to prevalence
      • dichotomous measures
      • accounts for wide variety of adverse childhood events
      • less detailed measurement of large set of victimization types
  21. What’s the ‘big picture’?
    • Finkelhor (2008) argued that we have “missed the bigger picture” and need to see child victimization in a fresh light:
    • “People have been too intensely focused on particular threats such as sexual abuse, bullying, or exposure to domestic violence”
    • Finkelhor (2008), p. vii
    • When examined over a child ’s life-course, are all events equally traumatising?
    • Does child maltreatment play a particularly important role?
  22. Aim
    • Use data from a moderately large, representative study of young adults in Australia
    • Use their retrospective reports of experiences of child maltreatment and victimization to understand the overlap in occurrence, and the relationship to current wellbeing
    • Examine the value of both the multi-type maltreatment and poly-victimization concepts
  23. Methodology: ATP
    • Australian Temperament Project – a longitudinal community study commenced with over 2,400 infants who were representative of the state of Victoria, Australia in 1983
    • Has included parent, teacher, nurse and self-reports
    • Current analyses are based on data collected in 2006-07 when young people were aged 23-24
    • Focus: retrospective reports of family experiences prior to age 18
  24. Measures
    • Childhood family experiences
    • Supportive parent-child/family relationships during childhood
    • Parental mental health problems; substance use problems
    • Poverty
    • Child maltreatment
      • Sexual abuse, physical abuse, emotional abuse, neglect; witnessing interparental family violence
    • Bullying by peers
      • Verbal abuse, physical abuse, exclusion
  25. Measure of maltreatment
    • (1) “No maltreatment” group ( n = 768, 77% of the sample). These individuals did not report any experience of child maltreatment;
    • (2) “Single maltreatment” group ( n = 153, 15% of the sample). These individuals reported one form of maltreatment; and
    • (3) “Multiple maltreatment” group ( n = 79, 8% of the sample). These individuals reported two or more forms of maltreatment.
  26. Results: Multi-type maltreatment
    • Summary of connections between multi-type maltreatment and psychosocial outcomes

      Problem psychosocial outcomes Depression +
      Anxiety +
      Binge drinking  
      Illicit drug use  
      Antisocial behaviour  
      Long term health problems  
      Positive psychosocial outcomes Civic action and engagement  
      Personal strengths -
      Social competence  
      Trust in others  
      Trust in authorities  
  27. Adult adjustment problems and child maltreatment / multi-type maltreatment
    • Graph
  28. Personal strengths and multi-type maltreatment
    • Graph
  29. Measurement of poly-victimization
    • (1) “No victimisation” group ( n = 464, 46% of sample). These participants did not report any form of either maltreatment or bullying;
    • (2) “One victimisation” group ( n = 219, 22% of sample). These participants reported one form of either maltreatment or bullying;
    • (3) “Low polyvictimsation” group ( n = 256, 26% of the sample). These participants reported 2-3 types of victimisation; and
    • (4) “High polyvictimisation” group ( n = 60, 6% of sample). These participants reported four or more types of victimisation.
  30. Results: Poly-victimization
    • Summary of connections between poly-victimization and psychosocial outcomes

      Problem psychosocial outcomes Depression +
      Anxiety +
      Binge drinking  
      Illicit drug use  
      Antisocial behaviour +
      Long term health problems +
      Positive psychosocial outcomes Civic action and engagement  
      Personal strengths -
      Social competence  
      Trust in others  
      Trust in authorities -
  31. Adult adjustment problems and poly-victimization
    • Graph
  32. Personal strenghts and poly-victimization
    • Graph
  33. Measurement of maltreatment vs other forms of victimization
    • (1) “No maltreatment or bullying” group (n = 451, 46% of sample). These individuals reported neither maltreatment nor bullying;
    • (2) “Bullying but no maltreatment” group (n = 292, 30% of sample). These individuals reported at least one form of bullying but no forms of maltreatment;
    • (3) “Maltreatment but no bullying” group (n = 88, 9% of sample). These individuals reported at least one form of maltreatment but no forms of bullying; and
    • (4) “Maltreatment and bullying group” group (n = 149, 15% of sample). These individuals reported at least one form of both maltreatment and bullying.
  34. Results: maltreatment vs. other victimization
    • Summary of connections between victimization type (i.e., bullying, child maltreatment, or both) and psychosocial outcomes

      Problem psychosocial outcomes Depression +
      Anxiety +
      Binge drinking  
      Illicit drug use  
      Antisocial behaviour +
      Long term health problems +
      Positive psychosocial outcomes Civic action and engagement -
      Personal strengths -
      Social competence  
      Trust in others  
      Trust in authorities  
  35. Adult adjustment problems and maltreatment vs. other victimization
    • Graph
  36. Personal strengths and maltreatment vs. other victimization
    • Graph
  37. Discussion
    • Multi-type maltreatment associated with greater adjustment problems than either no maltreatment or single types of maltreatment
    • Similar pattern, but weaker, with personal strengths
    • High levels of poly-victimization over entire childhood even more strongly related to adjustment problems and low levels of personal strengths in young adults
  38. Incidence vs prevalence
    • Different stories emerge when assessing victimization in the past 12 months vs. over the entire period of childhood/adolescence:
    • In analyses using the lifetime version of JVQ, Finkelhor acknowledges:
    • “Only two types of victimization - specifically experiencing any child maltreatment or any sexual assault - continued to make a substantial (and significant) contribution to the trauma symptoms, even after controlling for lifetime poly-victimization. However, the other measures of victimization or victimization severity did not.” (Finkehor et al., 2009 p. 408)
  39. Conclusions
    • Maltreatment and other child victimization experiences routinely “co-occur”
    • Adding childhood experiences of peer victimization – particularly verbal abuse, physical abuse and exclusion by peers – enhances the association with adult outcomes
    • Those with the highest levels of bullying and abuse had markedly higher levels of distress
    • Results demonstrate the value of both the multi-type maltreatment and poly-victimization concepts for understanding developmental trauma and its impact on the wellbeing of (non-clinical) young adults
  40. Implications
    • There is a role for broad measures of a wide variety of victimization types
    • To account for the potential superficiality of such wide-ranging measures, there is also a role for more detailed measures of specific victimization experiences
    • There is a role for measuring victimization in terms of incidence, and prevalence
    • Although other forms of victimization (e.g., bullying) strengthen the association with adult adjustment problems, it appears that child maltreatment is still the major contributor
  41. Contact details
    • Dr Daryl Higgins
    • Deputy Director (Research)
    • Australian Institute of Family Studies
    • www.aifs.gov.au
  42. References
    • Buckle, S., Lancaster, S., Powell, M. B., Higgins, D. J. (2005). The relationship between child sexual abuse and academic achievement in a sample of psychiatric adolescent inpatients. Child Abuse & Neglect, 29, 1031-1047.
    • Finkelhor, D. (2008). Child victimization: Violence, crime, and abuse in the lives of young people. Oxford: OUP.
    • Higgins, D. J. (2004). Differentiating between child maltreatment experiences. Family Matters, 69, 50-55. Online: < http://www.aifs.gov.au/institute/pubs/fm2004/fm69/dh.pdf>
    • Higgins, D. J., & McCabe, M. P. (2001). The development of the Comprehensive Child Maltreatment Scale. Journal of Family Studies, 7 , 7-28.
    • Higgins, D. J., & McCabe, M. P. (2001). Multiple forms of child abuse and neglect: Adult retrospective reports. Aggression and Violent Behavior: A Review Journal, 6 , 547-578.
    • Higgins, D. J., & McCabe, M. P. (2000). Relationships between different types of maltreatment during childhood and adjustment in adulthood. Child Maltreatment, 5 , 261-272.
    • Higgins, D. J., & McCabe, M. P. (2000). Multi-type maltreatment and the long-term adjustment of adults. Child Abuse Review, 9 , 6-18.
    • Higgins, D. J., & McCabe, M. P. (1998). Parent perceptions of maltreatment and adjustment in children. Journal of Family Studies, 4 , 53-76.
    • Higgins, D. J., & McCabe, M. P. (1994). The relationship of child sexual abuse and family violence to adult adjustment: Toward an integrated risk-sequelae model. Journal of Sex Research, 31 , 255-266.
  43. References – Table 1 (5 types)
    • Bevan, E., & Higgins, D. J. (2002). Is domestic violence learned? The contribution of five forms of child maltreatment to men's violence and adjustment. Journal of Family Violence, 17(3), 223-245.
    • Dong, M., Anda, R. F., Felitti, V. J., Dube, S. R., Williamson, D. F., Thompson, T. J., et al. (2004). The interrelatedness of multiple forms of childhood abuse, neglect, and household dysfunction. [doi: DOI: 10.1016/j.chiabu.2004.01.008]. Child Abuse & Neglect, 28(7), 771-784.
    • Higgins, D. J. (2003). The relationship of childhood family characteristics and current attachment styles to depression and depressive vulnerability. Australian Journal of Psychology, 55(1), 9-14.
    • Higgins, D. J., & McCabe, M. P. (1998). Parent perceptions of maltreatment and adjustment in children. Journal of Family Studies, 4(1), 53-76.
    • Higgins, D. J., & McCabe, M. P. (2000a). Multi-Type Maltreatment and the Long-Term Adjustment of Adults. [Article]. Child Abuse Review, 9(1), 6-18.
    • Higgins, D. J., & McCabe, M. P. (2000b). Relationships between different types of maltreatment during childhood and adjustment in adulthood. Child Maltreatment, 5(3), 261-272.
    • Higgins, D. J., & McCabe, M. P. (2001). The development of the Comprehensive Child Maltreatment Scale. Journal of Family Studies, 7(1), 7-28.
    • Higgins, D. J., & McCabe, M. P. (2003). Maltreatment and Family Dysfunction in Childhood and the Subsequent Adjustment of Children and Adults. Journal of Family Violence, 18(2), 107-120.
    • McGee, R. A., Wolfe, D. A., & Wilson, S. K. (1997). Multiple maltreatment experiences and adolescent behavior problems: Adolescents' perspectives. Development and Psychopathology, 9(1), 131-149.
    • Sesar, K., Zivcic-Becirevic, I., & Sesar, D. (2008). Multi-type maltreatment in childhood and psychological adjustment in adolescence: Questionnaire study among adolescents in Western Herzegovina Canton. Croatian Medical Journal, 49(2), 243-256.
    • Stevens, M., & Higgins, D. J. (2002). The Influence of Risk and Protective Factors on Burnout Experienced by Those who Work with Maltreated Children. [Article]. Child Abuse Review, 11(5), 313-331.
    • Vranceanu, A. M., Hobfoll, S. E., & Johnson, R. J. (2007). Child multi-type maltreatment and associated depression and PTSD symptoms: The role of social support and stress. Child Abuse and Neglect, 31(1), 71-84.
  44. References – Table 2 (polyvictimization)
    • Cuevas, C. A., Finkelhor, D., Ormrod, R., & Turner, H. (2009). Psychiatric diagnosis as a risk marker for victimization in a national sample of children. Journal of Interpersonal Violence, 24 (4), 636-652.
    • Elliott, A. N., Alexander, A. A., Pierce, T. W., Aspelmeier, J. E., & Richmond, J. M. (2009). Childhood victimization, poly-victimization, and adjustment to college in women. Child Maltreatment, 14 (4), 330-343.
    • Finkelhor, D., Ormrod, R., Turner, H., & Holt, M. (2009). Pathways to poly-victimization. Child Maltreatment, 14 (4), 316-329.
    • Finkelhor, D., Ormrod, R. K., & Turner, H. A. (2007a). Poly-victimization: A neglected component in child victimization. Child Abuse and Neglect, 31 (1), 7-26.
    • Finkelhor, D., Ormrod, R. K., & Turner, H. A. (2007b). Polyvictimization and trauma in a national longitudinal cohort. Development and Psychopathology, 19 (1), 149-166.
    • Finkelhor, D., Ormrod, R. K., & Turner, H. A. (2007c). Re-victimization patterns in a national longitudinal sample of children and youth. Child Abuse and Neglect, 31 (5), 479-502.
    • Finkelhor, D., Ormrod, R. K., & Turner, H. A. (2009). Lifetime assessment of poly-victimization in a national sample of children and youth. Child Abuse and Neglect, 33 (7), 403-411.
    • Finkelhor, D., Ormrod, R. K., Turner, H. A., & Hamby, S. L. (2005). Measuring poly-victimization using the Juvenile Victimization Questionnaire. Child Abuse and Neglect, 29 (11), 1297-1312.
    • Ford, J. D., Elhai, J. D., Connor, D. F., & Frueh, B. C. (2010). Poly-Victimization and Risk of Posttraumatic, Depressive, and Substance Use Disorders and Involvement in Delinquency in a National Sample of Adolescents. [doi: DOI: 10.1016/j.jadohealth.2009.11.212]. Journal of Adolescent Health, 46 (6), 545-552.
    • Hamby, S., Finkelhor, D., Turner, H., & Ormrod, R. (2010). The overlap of witnessing partner violence with child maltreatment and other victimizations in a nationally representative survey of youth. [doi: DOI: 10.1016/j.chiabu.2010.03.001]. Child Abuse & Neglect, 34 (10), 734-741.
    • Turner, H. A., Finkelhor, D., & Ormrod, R. (2007). Predictors of receiving counseling in a national sample of youth: The relative influence of symptoms, victimization exposure, parent-child conflict, and delinquency. Journal of Youth and Adolescence, 36 (7), 861-876.
    • Turner, H. A., Finkelhor, D., & Ormrod, R. (2010). Poly-Victimization in a National Sample of Children and Youth. [doi: DOI: 10.1016/j.amepre.2009.11.012]. American Journal of Preventive Medicine, 38 (3), 323-330.

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