Measuring Output from Primary Medical Care, with Quality Adjustment

Workshop on measuring Education and Health Volume Output OECD, Paris 6-7 June 2007

Session 4.4

Aileen Simkins, Director, UK Centre for the Measurement of Government Activity

UK Centre for the Measurement of Government Activity

Summary

• Problem, concepts, terminology• Improvements to index of consultations• Measuring impact of primary medical care on

health outcomes• Quality adjusted index of consultations

Problem: Data Sources

• Spending is measured by organisational unit – money paid to general medical practices

• Main data sources are based on administrative mechanisms of payment

• Output of general practice is part of wider healthcare – but hard to track overall pathway

• Unit of activity from general practice is a consultation with a doctor or nurse

• NHS does not count consultations: use household survey (recall bias?)

Concepts: Unit of Output

• Measure output as activity with results – attributable incremental impact on outcome

• Outcome of consultation – information, reassurance, improvement in health status...

• Seek data source to link measures of health status to actions of general practice

• ‘Make me better’ – short term, long term? Compare with initial symptoms, or counterfactual?

Terminology: UK Developments

• 2004 new general practice payment system: Quality and Outcomes Framework (QOF)

• Points for reaching defined indicators – many process, some outcome

• National data from 2004 forwards• QRESEARCH separate system linking GP

records, historic series, more flexible for analysis – large sample, quite representative

Index of Consultations

• Current National Accounts measure: from General Household Survey

• Sample of 20,000 adults; taken most years; question based on recall over last 2 weeks

• Analysed for ‘consultation rate by age band’ and consultation type (fewer home visits, more nurses)

• For NA, grossed up by population estimates to give total count of consultations, by consultation type

• Index uses cost weights for different consultation types

• Errors? wide confidence intervals on growth rate

Consultations Measured from Household Survey

0

50,000,000

100,000,000

150,000,000

200,000,000

250,000,000

300,000,000

1995

/96

1996

/97

1997

/98

1998

/99

1999

/00

2000

/01

2001

/02

2002

/03

2003

/04

2004

/05

2005

/06

2006

/07

No

. of

Co

ns

ult

ati

on

s

GHS GPs Practice Nurses

Project: Improve Consultation Series

• ONS, DH, Health and Social Care Information Centre, QRESEARCH, University of York

• Count of consultations from QRESEARCH practices, by type, grossed up

• Grossing up uses regression model which corrects for under-representation

• Based on 489 out of 8,750 practices, not 20,000 out of 50,000,000 people – smaller confidence intervals

New Consultation Series

0

50,000,000

100,000,000

150,000,000

200,000,000

1995

/96

1996

/97

1997

/98

1998

/99

1999

/00

2000

/01

2001

/02

2002

/03

2003

/04

2004

/05

2005

/06

2006

/07

No

. of

Co

ns

ult

ati

on

s

QRESEARCH GPs Practice Nurses

Advantages of QRES over GHS

• Uncertainty in the activity growth is halved• Data are more timely• Calendar & financial year and quarterly data

available• Information available on quality of treatment• Longer Practice Nurse series• Smoother trends in consultation numbers• Full year’s data (not 2 week sampling)• Based on stored information (not respondents'

memories)

Measuring the Impact of Primary Medical Care on Health Outcomes

• Selected indicators defined by QOF• 5 years data from QRESEARCH – quarterly,

April 2001–6• Considered: hypertension, coronary heart

disease, stroke, diabetes, chronic kidney disease, epilepsy

• Indicators mainly on measured blood pressure and cholesterol – within target range

• Data defects in some series – changing clinical definitions, changing recording practice

Improved control for patients with high blood pressure

0

10

20

30

40

50

60

70

80

90

100

abso

lute

per

cent

age

Apr 01 Apr 02 Apr 03 Apr 04 Apr 05 Apr 06Quarter date

Hypertension4: Blood pressure recorded in last 9 months

Hypertension5: BP < 150/90 in the last 9 months

in 498 England general practices in QRESEARCH

© QRESEARCH 2006 version 12, overall registered population 3.4 million

achieving Hypertension4 and Hypertension5 indicatorsTrends in percentage of hypertension patients

Improved blood pressure and cholesterol control: heart disease

0

10

20

30

40

50

60

70

80

90

100

abso

lute

per

cent

age

Apr 01 Apr 02 Apr 03 Apr 04 Apr 05 Apr 06Quarter date

CHD6: BP < 150/90 in last 15 months

CHD8: Cholesterol < 5 mmo/l in last 15 months

in 498 England general practices in QRESEARCH

© QRESEARCH 2006 version 12, overall registered population 3.4 million

achieving CHD6 and CHD8 indicatorsTrends in percentage of coronary heart disease patients

Improved blood pressure and cholesterol control: stroke

0

10

20

30

40

50

60

70

80

90

100

abso

lute

per

cent

age

Apr 01 Apr 02 Apr 03 Apr 04 Apr 05 Apr 06Quarter date

Stroke6: BP < 150/90 in last 15 months

Stroke8: Cholesterol < 5 mmo/l in the last 15 months

in 498 England general practices in QRESEARCH

© QRESEARCH 2006 version 12, overall registered population 3.4 million

achieving Stroke6 and Stroke8 indicatorsTrends in percentage of stroke patients

Significance and Causality

• Results predict future extended lives, less disability, fewer hospital admissions, better for individuals and families

• Established medical good practice to reduce high blood pressure, cholesterol

• Wider public awareness – diet, exercise• Payment incentives: have other areas of health

got worse?

Quality Adjusted Consultation Index

• Weight together the 5 time series • Allow for what is not known• Multiply quality index into consultation index

Weightings for Aggregate Quality Index

• Where a condition has more than one outcome indicator, they are each given equal weight;

• Indicators for different conditions are combined in proportion to their prevalence;

• The indicators are assumed to account for either one third or one half of potential ‘quality’ , with other aspects assumed to remain constant

• Patients with none of these conditions are assumed to have received constant quality of care.

Quality Index

Quality Adjusted Consultation Index

GP & PN output with qual adj dampened by factor of 1/3

80.0

100.0

120.0

20

01

Q3

20

02

Q1

20

02

Q3

20

03

Q1

20

03

Q3

20

04

Q1

20

04

Q3

20

05

Q1

20

05

Q3

20

06

Q1

Quarter

Ind

ex

(2

00

2Q

1 =

10

0)

unadjusted quality adjusted

Next Steps

• Consultation index (no quality) into National Accounts June 2007, including revisions

• Paper on quality index to be published by DH, July 2007, then discussed in ONS productivity article Sept 2007

• Link outputs to inputs – productivity change• Improve epidemiological assumptions?• Wider range of clinical conditions?

Measuring Output from Primary Medical Care, with Quality Adjustment

Workshop on measuring Education and Health Volume Output OECD, Paris 6-7 June 2007

Session 4.4

Aileen Simkins, Director, UK Centre for the Measurement of Government Activity

UK Centre for the Measurement of Government Activity