Cancer Care Ontario’s policy states that they do not release information in cell sizes of N=5 or smaller. What does this mean?
N=5 means that Cancer Care Ontario will not disclose aggregate data with counts smaller or equal to five (5). For example, “4 incidents of breast cancer in Simcoe County in 1992” is a data set that could not be disclosed. The policy is meant to protect the privacy of individuals who may be identified because they have a rare type of cancer or live in a small geographic area where such data has the potential to identify them. Cancer Care Ontario will also consider the group in which the count applies (i.e. the denominator) and generally does not disclose counts within a city or postal code. Cancer Care Ontario may disclose counts within a region, county or Local Health Integration Network.
