General Register Office for S C O T L A N D information about Scotland's people 1 Small Area Population Estimates for Scotland Quality Assurance Harvey Snowling General Register Office for Scotland BSPS Conference, September 2006

General Register Office for S C O T L A N D information about Scotland's people 2 Overview of presentation Background Quality assurance SAPE vs. Administrative data Conclusions

General Register Office for S C O T L A N D information about Scotland's people 3 Background

General Register Office for S C O T L A N D information about Scotland's people 4 Small Area Population Estimates SAPE –Published October 2005 –Data zone population estimates by gender, age –Constrained by mid-year estimates at LA level SAPE 2005 –October 2006 publication

General Register Office for S C O T L A N D information about Scotland's people 5 Cohort-component method –'Base' population sex/age structure –Remove 'special' populations (armed forces, prisoners) –'Age-on' remainder by 1 year –Incorporate births, deaths, migration, asylum seekers –Replace updated 'special' populations –Constrain to mid-year LA estimates Methodology

General Register Office for S C O T L A N D information about Scotland's people 6 Geography Data zones –Scottish Neighbourhood Statistics –Built up from 2001 Census output areas –500 – 1,000 household residents –6,505 in Scotland –Fit local authority boundaries

General Register Office for S C O T L A N D information about Scotland's people 7 SAPE Summary Statistics

General Register Office for S C O T L A N D information about Scotland's people 8 Quality Assurance

General Register Office for S C O T L A N D information about Scotland's people 9 SAPE Quality Assurance Consultation with users – Local authorities, health boards and others – PAMS committee, SAPE working group Review of methodology – Cohort-component vs. Ratio change Comparison with administrative data

General Register Office for S C O T L A N D information about Scotland's people 10 SAPE vs. Administrative Data Results

General Register Office for S C O T L A N D information about Scotland's people 11 Comparisons done for... Children aged 5-14 ( ) –Child Benefit Database (DWP, HMRC) –School Population (2003–2004 only) School Census (SE) Estimated independent school pupils (GROS) Adults aged 65+ ( ) –Super Older Persons Database (DWP)

General Register Office for S C O T L A N D information about Scotland's people 12 Scotland, 2004

General Register Office for S C O T L A N D information about Scotland's people 13 Summary Statistics Age 5-14Age 65+ SAPECBDSPSAPESOPD No. of data zones6505 Minimum population30130 Maximum population Mean population th percentile Lower quartile Median Upper quartile th percentile Standard deviation

General Register Office for S C O T L A N D information about Scotland's people 14 SAPE (5-14) vs. Child Benefit Database counts, All data zones 2004

General Register Office for S C O T L A N D information about Scotland's people 15 SAPE (65+) vs. Older persons database counts, All data zones 2004

General Register Office for S C O T L A N D information about Scotland's people 16 Data Zones, 2004

General Register Office for S C O T L A N D information about Scotland's people 17 Data zone population differences for children aged 5-14, Aberdeenshire 2004

General Register Office for S C O T L A N D information about Scotland's people 18 Population estimates for children aged 5-14 in data zones S and S SAPE pop'nSAPE 5-14CBD 5-14SP 5-14 S n/a n/a S n/a n/a Population growth SAPE rate of growth slower than child benefit Possibly due to timing

General Register Office for S C O T L A N D information about Scotland's people 19 Data zone population differences for children aged 5-14, South Lanarkshire 2004

General Register Office for S C O T L A N D information about Scotland's people 20 Population estimates for children aged 5-14 in data zones S and S SAPE pop'nSAPE 5-14CBD 5-14SP 5-14 S n/a n/a S n/a n/a Population growth in 2004 Not reflected in child benefit database

General Register Office for S C O T L A N D information about Scotland's people 21 Data zone population differences for children aged 5-14, Angus 2004

General Register Office for S C O T L A N D information about Scotland's people 22 SAPE pop'nSAPE 5-14CBD 5-14SP 5-14 S n/a n/a Population estimates for children aged 5-14 in data zone S Stable population Discrepancy in 2001 carried forward to subsequent years

General Register Office for S C O T L A N D information about Scotland's people 23 Data zone population differences for children aged 5-14, Perth & Kinross 2004 Highlighted data zones have boarding schools

General Register Office for S C O T L A N D information about Scotland's people 24 Data zone population differences for adults aged 65+, Glasgow 2004

General Register Office for S C O T L A N D information about Scotland's people 25 Population estimates for adults aged 65+ in data zones S and S Adjacent data zones with stable populations Possibly residents of communal establishment allocated to wrong data zone SAPE pop'nSAPE 65+SOPD 65+ S S

General Register Office for S C O T L A N D information about Scotland's people 26 Data zone population differences for adults aged 65+, Renfrewshire 2004 Highlighted data zones have nursing homes

General Register Office for S C O T L A N D information about Scotland's people 27 Areas with discrepancies Rapidly growing/declining populations High number of independent school pupils Student areas Nursing homes, hospitals

General Register Office for S C O T L A N D information about Scotland's people 28 Other sources of discrepancy Timing of counts Starting from different point in 2001 CE residents allocated to wrong data zone Unknown discrepancies Administrative data

General Register Office for S C O T L A N D information about Scotland's people 29 Conclusions

General Register Office for S C O T L A N D information about Scotland's people 30 Overall picture Discrepancies mostly small No apparent systematic errors Most discrepancies in known or expected ‘problem areas’ But there are unexplained discrepancies

General Register Office for S C O T L A N D information about Scotland's people 31 Thank you Questions?