The value of HoNOS in assessing mental health symptom severity and social functioning in forensic outpatients

The Health of the Nation Outcome Scales (HoNOS) is used for routine outcome measurement in forensic outpatient mental health care. Until now, no research has been done on its psychometric properties and clinical value in this population. Statistical analyses on 3,951 forensic outpatients (general violence, domestic violence, property offense, and sexual offense) showed that at domain level internal consistency coefficients varied between .30 and .58. The item scores were heavily skewed with scores in the subclinical range. Non-parametric analyses revealed that, at item level, aggressive offenders scored significantly higher (but still subclinical) than other offender subgroups. Compared to general mental health samples, forensic outpatients scored significantly lower (mainly large effects) on the total rating. Based on these results, it is concluded that the HoNOS does not provide good psychometric properties nor clinical value for ROM purposes in forensic outpatients.