21. EARLY DEATHS: CANCER INDICATOR

TABLE 1 – INDICATOR DESCRIPTION

Information component	Pg 4 Health Summary – Indicator No 21
Subject category / domain(s)	How long we live and what we die of
Indicator name (* Indicator title in health profile)	Mortality rate from all cancers (*Early deaths: cancer)
PHO with lead responsibility	SEPHO
Date of PHO dataset creation	December 2006
Indicator definition	Mortality from all cancers, directly age-standardised rate, persons, under 75, 2003-05 (pooled), per 100,000 European Standard population
Geography	England, GOR, Local Authority: Counties, County Districts, Metropolitan County Districts, Unitary Authorities, London Boroughs (boundaries as at April 2006).
Timeliness	The Compendium mortality from all cancers indicator is updated annually, usually around November following the publication by ONS of the new year’s mortality extract (usually in May) and mid-year population estimates (usually August-September).
Rationale:What this indicator purports to measure	Early mortality from all cancers.
Rationale:Public Health Importance	Cancer is amongst the three leading causes of death at all ages except for pre-school age children in the UK. It accounts for 26% all deaths. If current incidence rates remain the same, by 2025 there will be an additional 100,000 cases of cancer diagnosed each year as a result of the ageing population. Inequalities exist in cancer rates between the most deprived areas and the most affluent.Early mortality from cancer is a direct measure of health care need as public health interventions for prevention, early diagnosis, effective treatment can all reduce the burden of cancer morbidity and mortality.
Rationale: Purpose behind the inclusion of the indicator	To estimate premature mortality due to cancer.To reduce premature deaths from cancer.
Rationale:Policy relevance	The directly age-standardised mortality rate from all cancers for persons aged under 75 is a target indicator in the Saving Lives: Our Healthier Nation strategy. The target is a 20% reduction by the year 2010 from the baseline rate in 1995-97.This measure supports delivery of the Department of Health PSA targets and LDP and is relevant to Choosing Health, Cancer NSF and Programme for Action.
Interpretation: What a high / low level of indicator value means	A high indicator value (red circle in health summary chart) represents a statistically significant higher rate of early deaths from cancer for that local authority when compared to the national value.A low indicator value (amber circle in health summary chart) represents a statistically significant lower rate of early deaths from cancer for that local authority when compared to the national value.
Interpretation: Potential for error due to type of measurement method	Coverage can be considered to be complete as the registration of deaths is a legal requirement. Data quality for the relevant fields (age, sex, underlying cause of death, area of residence) is extremely high. There is the potential for the underlying cause of death to be incorrectly attributed on the death certificate and, therefore, the cause of death misclassified.
Interpretation: Potential for error due to bias and confounding	The rates are age-standardised. This improves the comparability of rates for different areas, or between different time periods, by taking into account differences in the age structures of the populations being compared.
Confidence Intervals: Definition and purpose	A confidence interval is a range of values that is normally used to describe the uncertainty around a point estimate of a quantity, for example, a mortality rate. This uncertainty arises as factors influencing the indicator are subject to chance occurrences that are inherent in the world around us. These occurrences result in random fluctuations in the indicator value between different areas and time periods. In the case of indicators based on a sample of the population, uncertainty also arises from random differences between the sample and the population itself.The stated value should therefore be considered as only an estimate of the true or ‘underlying’ value. Confidence intervals quantify the uncertainty in this estimate and, generally speaking, describe how much different the point estimate could have been if the underlying conditions stayed the same, but chance had led to a different set of data. The wider is the confidence interval the greater is the uncertainty in the estimate.Confidence intervals are given with a stated probability level. In Health Profiles 2007 this is 95%, and so we say that there is a 95% probability that the interval covers the true value. The use of 95% is arbitrary but is conventional practice in medicine and public health. The confidence intervals have also been used to make comparisons against the national value. For this purpose the national value has been treated as an exact reference value rather than as an estimate and, under these conditions, the interval can be used to test whether the value is statistically significantly different to the national. If the interval includes the national value, the difference is not statistically significant and the value is shown on the health summary chart with a white symbol. If the interval does not include the national value, the difference is statistically significant and the value is shown on the health summary chart with a red or amber symbol depending on whether it is worse or better than the national value respectively.

TABLE 2 – INDICATOR SPECIFICATION

Indicator definition: Variable	Mortality from all cancers (ICD10 C00-C97)
Indicator definition: Statistic	Directly age-standardised rate
Indicator definition: Gender	Persons
Indicator definition: age group	Under 75
Indicator definition: period	2003-05 (pooled**)** average of annual rates
Indicator definition: scale	Per 100,000 European Standard population
Geography: geographies available for this indicator from other providers	ONS area, Primary Care Organisation, Strategic Health Authority.Available from National Centre for Health Outcomes Development (NCHOD) websitewww.nchod.nhs.ukData can also be found at Neighbourhood Renewal Unit Public Service Agreement Floor Targets (www.fti.neighbourhood.gov.uk/default.asp).
Dimensions of inequality: subgroup analyses of this dataset available from other providers	Age, gender available from NCHOD.
Data extraction: Source	NCHOD.
Data extraction: source URL	Data received directly from NCHOD.
Data extraction: date	Dec 2006
Numerator: definition	Deaths from all malignant neoplasms, classified by underlying cause of death (ICD10 C00-C97), registered in the respective calendar years 2003-05, in people aged under 75.
Numerator: source	Office for National Statistics (ONS)
Denominator: definition	2001 census based mid-year population estimates for respective calendar years 2003 to 2005, people aged under 75 (current as at 24 August 2006).
Denominator: source	ONS
Data quality: Accuracy and completeness	Coverage can be considered to be complete as the registration of deaths is a legal requirement. Data quality for the relevant fields (age, sex, underlying cause of death, area of residence) is extremely high. Area of residence is allocated by ONS using the postcode and the National Statistics Postcode Directory – records without a valid area code are excluded but the number of such records is negligible.

TABLE 3 – INDICATOR TECHNICAL METHODS

Numerator: extraction	Extraction by NCHOD.
Numerator: aggregation /allocation	Deaths were assigned to geographical areas using the area code supplied in the mortality extract.  This is derived from postcode of residence by the ONS using the National Statistics Postcode Directory (NSPD).
Numerator data caveats	Area of residence is allocated by ONS using the postcode and the National Statistics Postcode Directory – records without a valid area code are excluded but the number of such records is negligible.Mortality counts are derived from the annual DH mortality extract supplied by ONS and are based on the original underlying cause of death for which there is nearly 100% coverage on the mortality register.
Denominator data caveats	Data are based on the latest revisions of ONS mid-year population estimates for the respective years, current as at 24 August 2006.
Methods used to calculate indicator value	The directly age-standardised rate (DSR) is the rate of events that would occur in a population with a standard age structure if that population were to experience the age-specific rates of the subject population. The standard population used is the European Standard Population. The age groups used are: Under 1, 1-4, 5-9,…, 80-84, 85+. The rate for 2003-05 has been calculated as the simple average of the individual annual rates. The rate is expressed per 100,000 population.
Small Populations: How Isles of Scilly and City of London populations have been dealt with	Isles of Scilly and City of London are excluded from the lower tier datasets but included in England, Regional and County figures.
Disclosure Control	None applied.
Confidence Intervals calculation method	Confidence intervals for the age-standardised rates were calculated using a normal approximation, i.e. +/- 1.96 standard errors. The standard errors are obtained using the method described by Breslow and Day ,  but modified to use the binomial variance for a proportion to estimate the variances of the crude age-specific rates.  This method is likely to be unreliable when there are fewer than 50 cases in an area, hence confidence intervals for rates based on less than 50 cases should be viewed with caution.

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