Cancer rates over 4 year intervals divided by sex, edited to include averages and combined rates. Rank is out of 350. Lower is better.

SIR: Standardized Incidence Ratio = (Observed / Expected) * 100

CI: Confidence Intervals

Select a city to view data.

Note - if the threshold of observed cases is under 5, the Rank, SIR, and CI are marked as Not Applicable. (For example, if there an observed case of "1" for a town, and expected of "0.2" there would be an absurdly high SIR of "500").

Data source: MA Cancer Incidence City Town Supplement.

Source Code

Source code for this site, as well as the source that parsed and generated the data.

Important Disclaimer

This data is sourced from MA Cancer Incidence City Town Supplement with additional data (averages, combined data, and rankings) provided "as-is". The reasons for an elevated rate (overall or for a specific cancer) could vary wildly - so take this data as a starting point, and not any sort of definitive assessment of cancer risk for a city.

Supplemental Information

Source: City Town Supplement 2011-2015.

Observed and Expected Case Counts

The observed case count (Obs) for a particular type of cancer in a city/town is the actual number of newly diagnosed cases among residents of that city/town for a given time period.

A city/town’s expected case count (Exp) for a certain type of cancer for this time period is a calculated number based on that city/town’s population distribution (by sex and among eighteen + age groups) during the time period observed.

Standardized Incidence Ratios

A Standardized Incidence Ratio (SIR) is an indirect method of adjustment for age and sex that describes in numerical terms how a city/town’s cancer experience in a given time period compares with that of the state as a whole.

A SIR of 100 is expected. So a SIR of 105 is 5% higher than expected, and a SIR of 90 is 10% lower.

Statistical Significance and Interpretation of SIRs

The interpretation of the SIR depends on both how large it is and how stable it is. Stability in this context refers to how much the SIR changes when there are small increases or decreases in the observed or expected number of cases.