Note on data quality issues relevant to the Registry's year 2005 closedown

The Thames Cancer Registry's Management Group agreed to 'close down' the incidence year 2005 on 27 July 2007. Closedown means that the data collected by the Registry for the given diagnosis year are sufficiently complete and of sufficient quality for reports and publications. Additional data quality work, as a result of the Registry's boundary change and registration database upgrade during the registration year, necessitated that closedown take place a month later than planned. A snapshot of the Registry's database was taken on 27 July 2007 on which to base the Registry's 2005 Annual Report and other analysis and research work up to the next closedown in June 2008.

Incidence

At 2005 closedown the Registry had registered 48454 invasive cancers (C00-C97, excluding basal cell carcinoma of the skin), diagnosed in 2005 amongst the residents of the Registry's post-April 2006 catchment area (the counties of London, Kent, Surrey and Sussex). This is 101% of the number expected on the basis of similar incidence counts for the three preceding diagnosis years.

DCO proportion

The death certificate only (DCO) proportion of the 48454 registrations is 3.9%, an improvement on the 2004 closedown proportion, 4.6%. The proportion, although improved, remains high in West London and Sussex. The primary strategy of improving the completeness of case ascertainment remains in place. Additionally, a full review of the Registry's tracing process for DCO registrations in these areas is under way.

Ascertainment issues

Through significant effort, the Registry has greatly improved its access to pathology data. Of the 45 pathology laboratories in the Registry’s catchment area, 42 are now regularly providing information.

This year the Registry has exchanged information with one of our two breast screening quality assurance reference centres (QARCs), London, including 2004 and 2005 screen detected cases. Data is expected from the South East Coast QARC.

New registrations are submitted by the Registry to the Office for National Statistics (ONS). These are traced and flagged on the NHS Central Register (NHSCR). This enables ONS to provide the Registry with NHS numbers for the flagged patients and with death certificates when the flagged patients die. ONS also provide the Registry with the death certificates of all persons who die of or with cancer, whose deaths are registered in the Registry's catchment area.

At closedown, of the 48454 registrations, 99% had been submitted to ONS. Because of a delay in processing at ONS, only 22% had been processed at the Registry to add confirmation of flagging on NHSCR and an NHS number. This should be resolved by the end of the year.

98% of the 48454 registrations had a valid NHS number at closedown. This year the Registry has improved the timeliness of its NHS number ascertainment through extensive use of the NHS Strategic Tracing Service.

99% of death certificates received from ONS which may relate to tumours diagnosed in 2005 were fully processed before closedown. However, flagged patient death certificates were not received for the cases affected by the ONS processing delay. The impact of this on the completeness of the Registry's death information for 2005 cases is uncertain; this will be assessed over the next few months as the delay is resolved.

The Registry's 2005 Annual Report will cover the geographic area of London, Kent, Surrey and Sussex. The Registry's 2004 Annual Report covered the Registry's area prior to 1 April 2006: the counties of Essex, Hertfordshire, London, Kent, Surrey and Sussex.

On 1 April 2006, all cancer registration responsibility for the Thames Cancer Registry part of the East of England Government Office Region (GOR) passed to the Eastern Cancer Registration and Information Centre (ECRIC).

Information requests regarding the former Thames Cancer Registry part of the East of England GOR should be made to ECRIC.

Quality of cancer registration in South East England as at 27 July 2007 by cancer network

Year of diagnosis: 2005

Back to top | Home | Address | What we do | Information | Research | Staff | Links