**Background:** Research has established that individuals with criminal convictions experience worse health outcomes than non-convicted persons, including higher rates of physical illness, mental health problems, substance use, and injury. However, few longitudinal studies have examined these associations across generations or compared male and female convicted persons in community (non-incarcerated) samples. The Cambridge Study in Delinquent Development (CSDD) provides a unique opportunity to investigate intergenerational patterns, having followed 411 London males (G2) from age 8-9 in 1961-62, their parents (G1), and their children (G3). Prior CSDD research found that convicted G2 males were healthier at age 18 but relatively unhealthy by age 48, with higher rates of mental illness and hospitalizations. The present study reports the first analyses of health and convictions in the third generation, comparing G3 males and females to their G2 fathers.
**Methods:** The CSDD originally included 411 G2 boys (born 1953) from a working-class area of South London, 87% White British. Between 2004 and 2013, biological G3 children aged 18+ were interviewed. Of 653 eligible G3 children, 551 were interviewed (84.4%): 291 of 343 G3 males (84.8%) and 260 of 310 G3 females (83.9%). The present analysis includes 530 G3 individuals (275 males, 255 females) with complete health and offending data. G3 children were interviewed at average age 25 and asked to report illnesses, injuries, accidents, and hospitalizations in the previous 5 years. Convictions (including cautions) were obtained from the Police National Computer (PNC), counting only standard-list (more serious) offenses. To control for age differences, only convictions up to age 25 were used. Odds ratios (ORs) were calculated with Haldane-Anscombe corrections for zero cells, and standard errors were adjusted for clustering within G2 families (ICC=0.27 for G3 males, 0.08 for G3 females).
**Key Results:** Among G3 males, 29.5% had convictions (vs. 43.9% of G2 males); among G3 females, 11.0% had convictions. Convicted G3 males had significantly higher odds of mental illness (OR=2.39, 95% CI 1.58-3.58), self-harm (OR=2.71, 95% CI 1.97-3.87), and drug use requiring medical treatment (OR=6.48, 95% CI 4.03-10.12) compared to non-convicted G3 males. Physical illness (OR=1.16, 95% CI 1.14-1.80) and hospitalizations (OR=0.80, 95% CI 0.65-1.01) were not significantly different. For injuries, convicted G3 males had higher odds of industrial accidents (OR=1.98, 95% CI 1.50-2.63), sports injuries (OR=1.98, 95% CI 1.45-2.43), and fight injuries (OR=2.33, 95% CI 1.41-3.62), but lower odds of road accidents (OR=0.33, 95% CI 0.12-0.60). Convicted G3 females showed a strikingly different pattern: they had significantly lower odds of physical illness (OR=0.67, 95% CI 0.66-0.99), mental illness (OR=0.39, 95% CI 0.25-0.63), hospitalizations (OR=0.67, 95% CI 0.52-0.87), and self-harm (OR=0.63, 95% CI 0.50-0.84) compared to non-convicted females. However, they had significantly higher odds of drug use (OR=2.78, 95% CI 2.15-3.59) and road accidents (OR=2.43, 95% CI 1.71-3.44). The ORs for G2 convicted males were remarkably similar to G3 convicted males for mental illness (OR=5.20, 95% CI 2.66-10.10) and drug use (OR=6.40, 95% CI 0.74-55.25), though G2 males showed no significant differences in physical illness or hospitalizations. For injuries, only fight injuries showed similarity across generations (G2 males OR=2.35, 95% CI 1.13-4.87).
**Clinical Implications:** The findings demonstrate that convicted males in the third generation continue to show worse health than non-convicted males, replicating patterns observed in their fathers. The strong associations with mental illness, self-harm, and serious drug use highlight the need for integrated mental health and substance use interventions within criminal justice settings. The unexpected finding that convicted G3 females report better health than non-convicted females across most measures (except drug use and road accidents) requires further investigation but may reflect selection effects, differential health behaviors, or protective factors such as alcohol's anti-infective properties observed in earlier CSDD waves. The authors suggest that antisocial lifestyles likely drive health deterioration over time, and that interrupting intergenerational patterns of offending through cognitive-behavioral interventions could yield substantial health benefits. Limitations include the predominantly White British working-class sample (limiting generalizability), reliance on self-reported health data, and inability to examine causal pathways or within-offender heterogeneity (e.g., life-course-persistent vs. adolescence-limited trajectories). The study underscores the importance of prospective longitudinal designs with frequent health and offending measures to clarify causal mechanisms.