### Methodology

A range of healthcare providers and other services (for example, pathology laboratories) submit cancer incidence data for England (that is, the number of people diagnosed with cancer over time). This data is sent to the regional offices of the National Cancer Registration and Analysis Service (NCRAS), which is part of Public Health England.

The quality and accuracy of the data submitted by different sources may vary. The regional offices of NCRAS collate all the data for each patient, including checks for internal consistency of the sequence of dates, as well as which part of the body the cancer affects, its morphology and the patient’s sex. NCRAS also checks for duplicate registrations.

In recognition of the effect of natural variation, 95% confidence intervals are calculated around estimates for new cancer diagnoses at an early stage and these should be considered when interpreting results.

Confidence intervals are used to determine whether any differences in the figures are likely to be real, or due to natural variation.

In statistical terms, a 95% confidence interval means that if 100 random samples were taken from the data, then 95 times out of 100 the estimate would fall in this range (that is, between the upper and lower confidence interval). But 5 times out of 100 it would fall outside this range.

The width of the confidence interval varies with the number of cancer diagnoses upon which it is based. The smaller the number, the wider the confidence interval, because less data means greater uncertainty.

Therefore, for the White ethnic group, which has the largest number of new diagnoses, the confidence intervals range from 52.5% to 53.0% in 2016. For the Chinese ethnic group, which has the smallest number, the confidence intervals range from 52.2% to 60.7%.

### Suppression rules and disclosure control

Values based on less than 70% staging coverage are suppressed as they are considered unreliable.

### Rounding

Percentages are rounded to 1 decimal place.

### Related publications

### Further technical information

Public Health Outcomes Framework – indicator definitions and supporting information