Objective: This study (i) explores differences between a clinical sample of deliberate selfpoisoning (DSP) patients and a community sample who reported previous attempted suicide (AS); and (ii) examines correlates of suicidal behaviour in these groups compared with a community control group (CC) with no suicidal behaviour. Method: The study design was: case–case, case–control and cross-sectional population studies. A clinical sample of DSP (n = 51), a community sample of AS (n = 31) and a community sample with no suicidal behaviour (n = 842) were used, all aged 18–24 years. The DSP and AS groups were compared on several variables and two logistic regression models were developed for risk of (i) DSP and (ii) AS compared to community controls. Results: The adjusted odds ratios for DSP were: female gender (OR = 5.7, CI = 1.7–19.4), anxiety (OR = 7.4, CI = 2.2–25.1), affective (OR = 23.0, CI = 6.9–76.5), or substance-use disorder (OR = 19.2, CI = 5.6–65.4) and greater mental health related disability (OR = 0.5, CI = 0.3–0.7 for 1 SD decrease). For AS the results were: anxiety (OR = 9.4, CI = 1.7–52.8) or substance-use disorder (OR = 3.0, CI = 1.1–8.7) and greater mental health disability (OR = 0.5, CI = 0.4–0.7). Affective disorder was close to significant for the AS group (OR = 4.0, CI = 0.9–17.1). Conclusions: Correlates of DSP/AS were usually more powerful in the clinical group, but showed a similar pattern of psychiatric disorder and disability factors in both groups, supporting a continuum of risk factors across these groups. Interventions based on modifiable risk factors could target the same factors for public health, primary care or hospital populations: anxiety, depression and substance use disorders and mental health related disability.