1. Time trends in family risks and their impact Stephan Collishaw & Barbara Maughan MRC SGDP Centre Institute of Psychiatry Kings College London

2. Time trends in family risks Recent decades Marked changes in family demographicsMarked changes in family demographics –age at marriage / cohabitation –age at birth of first child –family size –partnership stability / breakdown –complexity of family forms Increases in psychosocial disorders among young peopleIncreases in psychosocial disorders among young people

3. Time trends in adolescent conduct problems 1974-1999 Collishaw et al, 2004

4. Questions do changing family patterns explain trends in child outcomes?do changing family patterns explain trends in child outcomes? do the same risk factors contribute todo the same risk factors contribute to –individual differences in behaviour problems? –overall levels of behaviour problems? does the impact of family risks change when their prevalence changes?does the impact of family risks change when their prevalence changes?

5. ONS Population Trends 102, 2000 & Social Trends 20, 1990 Divorce rate per 1,000 married population 1961-1999 (England & Wales)

6. Hypothesis increasing prevalence of divorce associated with reduction in impactincreasing prevalence of divorce associated with reduction in impact –pre-divorce selection effects less troubled familiesless troubled families less parental discordless parental discord –post-divorce consequences less social stigmaless social stigma increased awareness of impact for childrenincreased awareness of impact for children

7. Parental divorce and child outcomes meta analysis (Amato, 2001) Decade of publication

8. Parental divorce and child outcomes meta analysis (Amato, 2001) Decade of publication

9. UK Cohorts Ely et al, 1999; Sigle-Rushton et al, 2005 Cohort

10. Possible explanations change in nature of marital dissolutionchange in nature of marital dissolution –low discord divorce especially distressing for children increasing gap in economic well-beingincreasing gap in economic well-being –single-parent families not benefited from economic expansion

11. Aims update picture to include more recent cohortupdate picture to include more recent cohort examine 3 family indicatorsexamine 3 family indicators –family type –family income –family size explore changes in prevalence and impactexplore changes in prevalence and impact illustrate changes in correlatesillustrate changes in correlates test how far changing family risks account for rising levels of conduct problemstest how far changing family risks account for rising levels of conduct problems

13. Samples Age 16

14. Family-based correlates – Family type (single vs. step vs. intact) – Family income (<60% median vs. remainder) – Family size (4+ children vs. 1-3 children) Adolescent conduct problems – fighting – bullying – stealing – lying – disobedience Measures

15. ONS Population Trends 102, 2000 & Social Trends 20, 1990 Cohort 1 Cohort 2 Cohort 3 Divorce rate per 1,000 married population 1961-1999 (England & Wales)

16. Teenagers living with both birth parents

17. Teenagers living in a step-family

18. Teenagers living in single-parent households

19. Low income by cohort: intact families

20. Proportion of families in poverty: Single parent vs. intact families Single Intact

21. Increasing income-inequality: single parent vs. intact families OR = 8.5 Single Intact

22. Increasing income-inequality: single parent vs. intact families OR = 8.5OR = 10.1 Single Intact

23. Increasing income-inequality: single parent vs. intact families OR = 8.5OR = 10.1OR = 19.4 Single Intact

24. Family type and conduct problems by cohort Family type OR = 1.9

25. Family type and conduct problems by cohort Family type OR = 1.9 OR = 2.1

26. Family type and conduct problems by cohort Family type OR = 1.9 OR = 2.1 OR = 1.8

27. Family type and conduct problems by cohort Family type OR = 2.7

28. Family type and conduct problems by cohort Family type OR = 2.7 OR = 2.2

29. Family type and conduct problems by cohort Family type OR = 2.7 OR = 2.2 OR = 1.6

30. Summary: family type Risk factorExposureImpact Single parent familyUpNo change Step family UpDown?

31. Social Trends, 2002 Absolute household disposable income in the UK (1974-1999)

32. Social Trends, 2006 Relative poverty in the UK (1974-1999)

33. Relative poverty by study cohort

34. Relative poverty and conduct problems by cohort Low income OR = 1.4

35. Relative poverty and conduct problems by cohort Low income OR = 1.4 OR = 2.1

36. Relative poverty and conduct problems by cohort Low income OR = 1.4 OR = 2.1 OR = 1.7

37. Family size by cohort: % four or more children

38. Family size and conduct problems by cohort N children OR = 3.0

39. Family size and conduct problems by cohort N children OR = 3.0 OR = 2.3

40. Family size and conduct problems by cohort N children OR = 3.0 OR = 2.3 OR = 1.8

41. Summary of findings up to now Risk factorExposureImpact Single parent familyUpNo change Step family UpDown? Relative povertyNo changeUp Large family sizeDownDown

42. Conduct problems: high scores Total OR = 1.56 per cohort

43. What contributes to time trends in conduct problems?

44. What contributes to time trends in conduct problems?

45. What contributes to time trends in conduct problems?

46. What contributes to time trends in conduct problems?

47. Some conclusions 1. Parallel trends in risks and outcomes do not imply a causal link –Increase in divorce rate over the past 30 years –Increase in conduct problems over the same time period –However, trends in family type appear largely independent of trends in conduct problems

48. Some conclusions 2. Correlates of risk factors may change over time –E.g. Amato –Only had limited data with which to look at this –Socio-economic disadvantage even more strongly associated with single parenthood in more recent cohorts

49. Some conclusions 3. Implication: changes in impact of a risk factor as important as changes in exposure –Focus on changes in exposure insufficient –Also need to consider possible change in association between risk and outcome –E.g. 1: family type and conduct problems; impact the same or reduced over time –E.g. 2: relative poverty and conduct problems; impact gone up over time

50. Some conclusions. 4. Different explanatory models needed for understanding individual differences and level differences –Family type, income and size all associated with CP at individual level –But, trends in these aspects of family life only made modest contribution to understanding of level differences –Different factors may be relevant for the two

51. Time trends in family risks and their impact Stephan Collishaw & Barbara Maughan MRC SGDP Centre Institute of Psychiatry Kings College London

52. Prevalence and odds of low income by family type and cohort 8.510.119.4 1.62.21.6 OR =