Casemix: The New Zealand Journey Dr Barry Welsh Principal Advisor Ministry of Health New Zealand

The presentation covers Context Defining casemix and its research basis What is case class and purpose of casemix Health of the Nation Outcome Scales (HoNOS) Programme for the Integration of Mental Health Data (PRIMHD) Implementation of the casemix grouper The types of reports Current issues Conclusion

3 Policy and Strategic Context 2005

Context – some annual statistics - 146,000 people (over 3% of population) access specialist mental health and addiction services - 19,000 access once - 15,000 people are seen for more than 2 years (KPP group) - 7,000 people admitted acutely - 1,000 people are secluded - 5,800 people compulsory assessed under the Mental Health Act Significant variation in rates between boards

Casemix defined Casemix is simply defined as a “mix of cases” In New Zealand mental health casemix is defined by the CAOS study that covered clinical community and inpatient services – it did not include NGOs. Only evidenced based study of its kind in NZ

What is a case class Case classes apply to community and inpatient clinical services across Child and Youth and Adult A community case class is premised on episodes of 91 days (+- 14 days) bounded by HoNOS collections and uses the following variables to determine what class the episode is allocated to: - a persons age, ethnicity, legal status, HoNOS score, focus of care 56 year old, in the community, with HoNOS collections 91days (+- 14) apart, not under Mental Health Act and of European ethnicity having a functional gain focus of care is assigned to a particular class (AC05). NZ case mix has 42 different classes (including assessment) that can be rolled up into 7 branches

Purpose of casemix Quality improvement Outputs measurement Funding

HoNOS – Health of the Nation Outcome Scales Five scales (HoNOSCA,HoNOS, HONOS65+,HoNOS-secure, HoNOS-LD) HoNOS 12 items - ranging from problems with hallucinations and delusions through to problems with occupation and activities, on a scale of 0-4 with 4 being severe problems Measures clinically rated health wellbeing changes over time HoNOS changes useful for clinicians and clients to monitor progress

HoNOS – Health of the Nation Outcome Scales Mandated by the Ministry of Health for national collection in 2006 HoNOS data collected according to a protocol underpinned by 91 days +-14days in the community Te Pou plays a huge role in training, inter-rater reliability and improving collection rates Change in HoNOS scores used by the KPI project in New Zealand for inpatient admissions and discharges Ministry also publishes change in HoNOS scores for community and inpatient services publically

PRIMHD the national mental health data collection system Programme for the Integration of Mental Health Data (PRIMHD) superseded MHINC (Mental Health National Collection). Established in 2008 to collected activity and outcomes data from 20 DHB clinical mental health services and activity data from 250 NGOs. It collects HoNOS data according to the outcomes collection protocol (derived from CAOS study) from inpatient and clinical community services (91days days)

Example PRIMHD HoNOS Report

Implementation of casemix A complex algorithm has been applied to the PRIMHD data over (10 years since the CAOS study) Selects only valid episodes. Distributes valid episode into 42 different classes split by age, ethnicity, focus of care, mental health act, community or inpatient (can be grouped into 7 branches) A difficult process to implement - significant support from Te Pou PRIMHD casemix will provide 12 number of standard reports and adhoc queries. Case class reports can be drilled down to NHI (individual person) level.

Casemix reports available from PRIMHD 12 standard reports plus adhoc query capability The reports can be grouped – Percentage of Outcome Episodes by Casemix Branch and District Health Board (DHB) Mean Improvement in HoNOS, HoNOS65+ & HoNOSCA Total Scores Reports that look at the relative mean improvement (CARMI) in HoNOS scores by DHB, DHB teams, by branch and class Reports that look at PRIMHD reported activity (beds and community activity and activity duration) relative to the CARMI score by DHB, branch and class The Percentage of Inpatient and Community Activities Used in Episodes of Care

Example Casemix reports available from PRIMHD

Casemix issues We’ve done it! Offers an opportunity delve into the detail of HoNOS outcomes Casemix complex and not well understood by the sector A top down process - don’t see a case class walk through the door Low matched pair rates (32,882 community and assessment branch episodes for 91,000 adults seen in 2011) Risk that there will be little variation in change in outcome scores

Mean Class - Improvements

Conclusion Its been a long journey (over 10 years) to develop and implement casemix. Casemix is potentially a useful tool for quality improvement but still many hurdles to get over.