Measuring Output from Primary Medical Care, with Quality Adjustment

1. Aileen Simkins, Director, UK Centre for the Measurement of Government Activity Measuring Output from Primary Medical Care, with Quality Adjustment UK Centre for the Measurement of Government Activity Workshop on measuring Education and Health Volume Output OECD, Paris 6-7 June 2007 Session 4.4

2. Summary Problem, concepts, terminology Improvements to index of consultations Measuring impact of primary medical care on health outcomes Quality adjusted index of consultations

3. 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?)

4. 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?

5. 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

6. 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

7. Consultations Measured from Household Survey

8. 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

9. New Consultation Series

10. 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)

11. 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

12. Improved control for patients with high blood pressure

13. Improved blood pressure and cholesterol control: heart disease

14. Improved blood pressure and cholesterol control: stroke

15. 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?

16. Quality Adjusted Consultation Index Weight together the 5 time series Allow for what is not known Multiply quality index into consultation index

17. 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.

18. Quality Index

19. Quality Adjusted Consultation Index

20. 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?

21. Aileen Simkins, Director, UK Centre for the Measurement of Government Activity Measuring Output from Primary Medical Care, with Quality Adjustment UK Centre for the Measurement of Government Activity Workshop on measuring Education and Health Volume Output OECD, Paris 6-7 June 2007 Session 4.4