RESEARCH NOTE: Parental separation and adult psychological distress: evidence for the ‘reduced effect’ hypothesis

Parental separation has been linked to increased likelihood of reporting psychological distress in adulthood, but relatively little is known about how this association may have changed over time. One hypothesis is that as the experience of separation has become more common, the association with psychological distress will reduce (the ‘reduced effect’ hypothesis). Previous evidence using the British birth cohorts does not support this hypothesis, but past studies have several limitations which we aim to address. In this study we measure parental separation from birth, account for missing data and statistically test cohort differences using data from two British birth cohorts – the 1958 National Child Development Study (NCDS) and 1970 British Cohort Study (BCS). Despite these methodological improvements, we find little evidence to support the ‘reduced effect’ hypothesis: parental separation was associated with a similarly increased likelihood of reporting psychological distress in adulthood for men and women in both cohorts. UK divorce rates have increased rapidly since the mid-20 century (fig. 1). This trend translates into an increasing probability that children will experience family disruption across this period. A longitudinal link between parental separation and adult psychological distress indicates that parental separation occurring during childhood is associated with increased reporting of psychological distress in adulthood (e.g. Chase-Lansdale, Cherlin & Kiernan, 1995; Kendler, Shether, Garner, & Prescott, 2002; Kuh & Maclean, 1990; Rodgers, 1990; Rodgers & Pryor, 1998). However the experience of parental separation may change Rebecca Lacey, Mel Bartley, Hynek Pikhart, Mai Stafford, Noriko Cable, Lester Coleman Evidence for the ‘reduced effect’ hypothesis? 360 Figure 1 – Trend in the number of divorces, England and Wales, 1946-2009 Source: Data taken from ‘Divorces 1858-2003’ (Office for National Statistics 2006); ‘Marriage, divorce and adoption statistics. FM2 No 35’ (ONS 2010) over time because social institutions and organisations, such as marriage and the family, have links to individuals through social trajectories which change with life experiences and historical time (Elder, 1994). In particular it is thought that the association between parental separation and adult psychological distress will lessen over time (termed the ‘reduced effect’ hypothesis) through reducing stigma surrounding divorce, increasing availability of services (e.g. family mediation) and greater awareness of the importance of maintaining contact between children and both parents following separation (Ely, Richards, Wadsworth, & Elliott, 1999). There is some evidence to support this hypothesis, as the association between parental divorce and adult psychological health was found to be greater in studies conducted during the 1950s and 1960s (effect size=-0.31, p<0.001), compared to studies from the 1980s (effect size=-0.13, p<0.001) (Amato & Keith, 1991). However Ely and colleagues (1999) failed to support this hypothesis, not finding any change in the association between parental separation and children’s educational attainment in their comparison of three British birth cohorts (born in 1946, 1958 and 1970). Also Sigle-Rushton, Hobcraft, and Kiernan (2005) reported that the associations between parental divorce and adult psychological distress were similar in the 1958 and 1970 birth cohorts. Despite the lack of evidence for the ‘reduced effect’ hypothesis in the British birth cohorts, these and other studies have methodological limitations which may have affected the results and conclusions: for example, cohort differences in the association between parental divorce and adult outcomes were not statistically tested in some studies; only separations and divorces from midchildhood onwards were examined; and cases with missing values were dropped from the analyses. In this research note we aim to assess whether there is evidence for the ‘reduced effect’ hypothesis once these methodological problems have been addressed. In addition it has been suggested that girls may be more affected by parental separation than boys, as girls are more likely to take on excessive responsibilities in the home, or emotionally support a parent (Hetherington & Stanley-Hagan, 1999). Parental divorce has been found to be associated with an increase in adult affective disorders for women but not for men in some samples (see e.g. Rodgers, 1990), 0 20,000 40,000 60,000 80,000 100,000 120,000 140,000 160,000 180,000 1 4 1 4 1 5 1 5 1 5 1 6 1 6 1 6 1 7 19 73 19 76 1 7 1 8 1 8 1 8 1 9 1 9 1 9 2 0 2 0 2 0 2 0 N o . o f d iv o rc e s