Crime rates are higher among patients with schizophrenia than in the general population. Denmark has seen a substantial increase in the number of forensic patients since 1980 with annual growth rates reaching 7%. In the same period, the population of forensic patients with schizophrenia has increased from 50% to 75%. Evidence-based care for patients with schizophrenia is well-established in international and national guidelines. However, a possible association between quality of care and risk of crime among patients with schizophrenia has not previously been studied.

To study the association between quality of care and risk of crime among patients with schizophrenia.

This nationwide population-based follow-up study is based on the Danish National Indictor Project (DNIP), a national clinical database for patients with schizophrenia, and the Danish Crime Register, a national register of criminal offences. We include all incident and prevalent patients diagnosed with schizophrenia (ICD-10: F20.00-F20.99), who are Danish citizens and older than 18 years. All patients have been admitted as inpatients at a psychiatric ward in the period 1 January 2004 to 31 December 2007 (approx 20,000 patients). In DNIP quality of care is assessed as fulfilment of a set of quality of care criteria related to the diagnostic process, contact with the health care system, use of antipsychotic medication, evaluation of side effects, family intervention, psycho education, planned outpatient treatment by discharge and suicide prevention. All patients will be followed up for 1-year after discharge. We identified all convictions for both violent and property crimes in the population.

The effectiveness of systematic quality improvement initiatives in psychiatric care remains unclear.

To elucidate the adherence to recommended evidence-based guidelines in clinical practice.

To examine whether the quality of care among patients hospitalized with schizophrenia has changed following the implementation of a systematic monitoring and auditing program of hospital performance measures.

In a nationwide population-based cohort study, we identified 14,228 patients admitted to Danish psychiatric departments between 2004 and 2011 and registered in The Danish Schizophrenia Registry. The registry systematically monitors and audits the adherence to clinical guideline recommended processes of care at all Danish psychiatric hospital departments treating patients with schizophrenia.

The overall proportion of all relevant recommended processes of care delivered to the patients increased from 64 % to 76 % between 2004 and 2011. The adherence to a number of individual processes of care increased over time, including assessment of psychopathology using a diagnostic interview (Relative risk (RR) 2.01, 95 % CI: 1.50; 2.69), contact with relatives (RR 1.44, 95 % CI: 1.27; 1.62), psychoeducation (RR 1.33, 95 % CI: 1.18; 1.48), psychiatric aftercare (RR 1.06 95 % CI: 1.01; 1.11) and suicide risk assessment (RR 1.31, 95 % CI: 1.20; 1.43). However, improvements were not observed for all assessed processes of care and substantial variation remained between the hospitals.

Quality of care improved substantially from 2004 to 2011 among patients hospitalized with schizophrenia at Danish hospitals. However, continued efforts to reduce performance variation between hospitals are warranted.

The association between schizophrenia and quality of care for medical comorbidities in universal health care systems remains unclear.

To elucidate whether equal access also implies equivalent and sufficient care.

To compare the quality of care for heart failure, diabetes and chronic obstructive pulmonary disease (COPD) among patients with and without schizophrenia in Denmark.

In a nationwide population-based cohort study, we used Danish national registries to estimate the risk of receiving guideline recommended disease-specific processes of care between 2004 and 2013.

Compared to patients without schizophrenia, patients with schizophrenia had lower chance of receiving high overall quality of care (≥ 80% of recommended processes of care) for heart failure (Relative risk [RR] 0.67, 95% CI: 0.48-0.92), diabetes (RR 0.84, 95% CI: 0.79-0.89) and COPD (RR 0.82, 95% CI: 0.72-0.93) as well as lower chance of receiving individual disease-specific processes of care including treatment with beta-blockers (RR 0.87, 95% CI: 0.79-0.96) in heart failure care and measurement for albuminuria (RR 0.96, 95% CI: 0.93-0.99), eye examination at least every second year (RR 0.97, 95% CI: 0.94-0.99) and feet examination (RR 0.96, 95% CI: 0.93-0.99) in diabetes care. Diabetic patients with schizophrenia also had lower chance of receiving antihypertensive (RR 0.84, 95% CI: 0.73-0.96) and ACE/ATII inhibitors (RR 0.72, 95% CI: 0.55-0.94). In COPD care, patients with schizophrenia had lower chance of receiving LAMA/LABA medication (RR 0.92, 95% CI: 0.87-0.98), however, higher chance of treatment with non-invasive inhalation (RR 1.85, 95% CI: 1.61-2.12).

Quality of care for three medical comorbidities was suboptimal for patients with schizophrenia.

The authors have not supplied their declaration of competing interest.