Projected acute hospital demand in South East London Meic Goodyear Queen Mary University of London & South East London Public Health Network August/September 2005

Background to South East London (1) Six PCTs – Bexley, Bromley, Greenwich, Lambeth, Southwark, Lewisham All coterminous with London Boroughs 120 Wards ca. 1.5 Million residents

Background to South East London (2) Overlapping geographies: - Inner/Outer London Inner (Lambeth, Southwark, Lewisham) Outer (Bexley, Bromley Greenwich) - London Sub Regions: South (Bromley) East (Bexley, Greenwich, Lewisham) Central (Lambeth, Southwark) - Thames Gateway Zones

Background to South East London (3) Population: –Ethnically diverse –Highly mobile in most parts –Areas of significant deprivation –Growing Fast!

Hospitals in South East London Each PCT hosts a General or Teaching Hospital Lambeth’s & Southwark’s are managed as a single provider trust Policy decision: no new hospitals to be built

Hospitals most used by South East Londoners "Source: 2001 Census Output Area Boundaries. Crown copyright Crown copyright material is reproduced with the permission of the Controller of HMSO"

Questions and issues What will be the expected demand for hospital usage over the period to 2016? How to develop existing facilities Where to put new facilities (diagnostic/treatment centres etc)? Conflicting pressures - historical rise in demand year on year - Government policies to move services to community and restrict growth of emergency admissions

Data Sources – patient activity Inpatient utilisation: each PCT provided files of patient (“consultant episode”) data annually from Data from the national HES database was used for standardisation Outpatient utilisation: although this data is exchanged nationally, not all PCTs keep it available, so for the moment outpatients are assumed to follow the same patterns and flows as inpatients Typically there are 4-5 times as many outpatient attendances as inpatient episodes A&E data not suitable for use, and not easily to hand so not included in study

Data Sources – reference Standard NHS codes reference files NHS Postcodes file Ordnance Survey codepoint/addresspoint

Method(1) Establish baseline and assume constant rates Determine baseline usage patterns Work at lowest convenient geographical level Apply to best available population projections Investigate mismatch between existing provision and need (assuming total baseline meets total need, but not necessarily in the right places)

Method(2) Baseline: Average activity Apply to 2001 Census to get rates Work at Ward level Ward/provider flows where there is reasonable year-to-year consistency (90-95% of totals) 95% confidence intervals to handle uncertainty Ward centroid – provider distances as the crow flies by Pythagoras from geocodes; driving distance from Infomap software using shortest journey time as preference

Projected population growth SEL 2001 – 2016 per NELSHA/SELSHA “Blue Book”

Projected population growth SEL 2001 – 2016 per GLA Scenario 8.1

Projected population growth – 2016 Comparison GLA v Blue book by PCT

Thames Gateway “Zones of Change” "© Crown Copyright/database right An Ordnance Survey/EDINA supplied service."

TG Zones do not observe borough or ward boundaries "Source: 2001 Census Output Area Boundaries. Crown copyright Crown copyright material is reproduced with the permission of the Controller of HMSO"

Which population projections? GLA: by year, by age in years and 5-year age band, by Borough and ward. Includes data from Housing Capacity Study (HCS). Only part of TG development included, where that was included in the HCS. Issued in late Initially informed no TG included, subsequently this was corrected. No other ward-based projections are available so use these, with appropriate caveats, and revise calculations when these are updated.

Linking patients to geography Patient data – postcode, NHS hosp; PCT;GP & practice codes NHS Postcode file/ Ordnance Survey: NHS links to Postcode & geocoding Aggregate at ward level Analyse by Ward-provider Flows, distance, travel

Prince’s Ward, Lambeth (randomly chosen example) "Source: 2001 Census Output Area Boundaries. Crown copyright Crown copyright material is reproduced with the permission of the Controller of HMSO"

Outputs of Analysis (1) Annual totals with 95% CIs by age band

Outputs of Analysis (2)

Outputs of Analysis (3) Ward-provider flow proportions

Journeys at current patterns Admitted patients in South East London travel ca 4,000,000 person Kms per year to and from their admissions Assuming similar patterns for outpatients, total annual travel to and from hospitals in South East London will be in the million kilometres

Naïve assumption For environmental and for convenience of patients, wherever possible, patients should be treated at the hospital nearest their homes (most would choose this assuming equal quality of care)

“Excess distance” Calculate total current travel distances Calculate minimum travel distances on the basis of all journeys being to/from hospital nearest to home (ward centroid of patient’s address) Excess distance is the difference between these

South East London Admitted Patients: Fraction of mileage to hospitals other than the shortest journey "Source: 2001 Census Output Area Boundaries. Crown copyright Crown copyright material is reproduced with the permission of the Controller of HMSO"

Excess distance (2) "Source: 2001 Census Output Area Boundaries. Crown copyright Crown copyright material is reproduced with the permission of the Controller of HMSO"