Polypharmacy is not uncommon among people with a severe mental illness (SMI) who require long-term psychiatric care. These combinations of psychotropic drugs arise from the complexity and severity of these people’s psychiatric condition and comorbidity. However, treatment of many people with SMI is possibly based on poor and outdated diagnosis. 

Although changing medication may seem promising, it may be considered risky due to the long treatment history of many long-term residential patients, where earlier relapses make care professionals, relatives and patients careful about change. Nevertheless, it is important to investigate whether treatment is still in line with the actual diagnosis and not based on an outdated one.  

The DITSMI model (Diagnose, Indicate, and Treat Severe Mental Illness), a pharmacological protocol for re-assessing people with SMI, was created by GGNet and involves appropriate (re-)diagnosis in a multidisciplinary team. The model is based on a number of concepts and interventions, including a holistic diagnosis: the re-evaluation of a patient regarding different aspects of life, such as psychiatric, somatic and social functioning. 

This holistic diagnosis is established in a multidisciplinary team, including a psychiatrist, a psychologist, nurses, social workers, peer workers and occupational therapists, whereafter an appropriate treatment proposal is produced. 

In the three-year follow-up study on the effects of this model done by GGNet, DITSMI led to a shift in diagnosis for 50% of the participants and medication was altered in 67% of the cases. Furthermore, the use of antipsychotics dropped by 30%1.  

In the current project, we aim to implement the DITSMI model into the long-term residential setting.   

This research is made possible by a grant from ZonMw 

Project Partners:

  • Lentis
  • Trimbos-instituut
  • GGNet
  • IVM
  • MIND

Involved GRIP researchers:


  1. Veereschild HM, Noorthoorn EO, Nijman HLI, Mulder CL, Dankers M, Van der Veen JA, Loonen AJM, Hutschemaekers GJM (2020). Diagnose, indicate, and treat severe mental illness (DITSMI) as appropriate care: A three-year follow-up study in long-term residential psychiatric patients on the effects of re-diagnosis on medication prescription, patient functioning, and hospital bed utilization. European Psychiatry, 63(1), e47, 1–8 https://doi.org/10.1192/j.eurpsy.2020.46