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 +- 14 days)

Example PRIMHD HoNOS Report

Figure 3: Average total HoNOS score and number of collections for clients seen in 2009/10, at admission, review and discharge, by setting

n=6731

n=3546

n=1152

n=4886

n=20,108

n=96,862

n=10,793

n=8622

0

2

4

6

8

10

12

14

16

Admission Review Discharge (nofurther care)

Discharge(change oftreatmentsetting)

Admission Review Discharge (nofurther care)

Discharge(change oftreatmentsetting)

Inpatient setting Community setting

Average total HoNOS score

n = number of collections

Source: PRIMHD.

Example PRIMHD HoNOS Report

Significant Deterioration

HoNOS referral closures

Significant Improvement

No significant change

Significant Deterioration

HoNOS referral closures

Significant Improvement

No significant change

HoNOS referral closures

No significant change

Significant Deterioration

1 71 21 6 - 51 125 35 322 59 1

1 71 21 6 - 51 125 35 322 59 1

57.7 % 52.9 % 49.7 %

Report Run Date: 25/10/2012

Key Performance Indicator 1: Total HoNOS score (inpatients) – effect size largeReport Period: 02/07/2011 - 30/06/2012

Table 1: KPI 1 - Total HoNOS Score (Inpatients) – Effect Size Large

Organisation: Auckland DHB

ACUTE Inpatient units in-scope

Maori Pacific Other Overall

Team NameSignificant

ImprovementNo significant

changeSignificant

Deterioration

Significant Improveme

nt

HoNOS referral

closures

Te Whetu Taw era 22 18 - 168 444

Total 22 18 - 168 444

Auckland DHB Inpatient matched pair compliance % Inpatient matched pair compliance % Inpatient matched pair compliance % Inpatient matched pair compliance % 51.4 %

Implementation of casemix

• A complex algorithm has been applied to the PRIMHD data over 2011- 2013 (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

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.

barry_welsh@moh.govt.nz

www.tepou.co.nz