It is a well-established fact that Black students in the United States are more likely than other students to receive disciplinary referrals, and be suspended or expelled from school. For example, the U.S. Department of Education’s Civil Rights Data Collection notes that in 2013, Black students comprised 26 percent of all students in New York City schools, but made up 48 percent of in-school suspensions, 55 percent of out-of-school suspensions, and 65 percent of expulsions. Clearly, Black students in New York City are overrepresented in school discipline cases. Similar patterns persist across the country.

Disproportionality is often measured with the relative risk statistic, a measure that indicates the probability of a certain event (e.g., suspension) for one subgroup when compared to all other subgroups. You may be more familiar with the relative risk statistic in the context of health or medical literature – for example, that smokers are 23 times more likely to develop lung cancer than non-smokers. The same statistic, the relative risk, is used to measure disciplinary disproportionality. A relative risk of 1.00 indicates that the group you are measuring has an equal risk of the specified outcome, and a relative risk of 0.50 indicates the group you are measuring is half as likely to experience the specified outcome. A relative risk of 2.00 indicates the group you are measuring is twice as likely to experience the specified outcome. So how can an LEA or SEA measure disproportionality in a school, district, or state? To calculate the relative risk of disciplinary referral, you will need the following data points:

- Total enrollment, by race
- Total number of students receiving a disciplinary referral, by race

### To calculate the relative risk of a Black student receiving a disciplinary referral, use the following formula:

**(Number of Black students referred) /( Black Enrollment)**

**[(Number of students referred – Number of Black students referred) / (Total Enrollment – Black Enrollment)]**

A simplified version of the formula is the percent of Black students receiving a referral divided by the percent of all other students receiving a referral.

Let’s use data from a real school district to further understand how to calculate the relative risk. District X has a total enrollment of 21,337 students; 11,311 of these students are Black. In total, 5,444 students in the district received at least one disciplinary referral last year; of these, 3,678 were Black students. The calculation for the relative risk of Black students in the district is as follows:

**3678 / 11,311**

**(5444 – 3678) / (21,337 – 11,311)**

The result of the formula is 1.85, indicating that Black students are *1.85 times more likely* as other students to receive a disciplinary referral. To measure the relative risk for other groups of students, substitute the referral totals of Black students for another group. Relative risk can also be calculated for students with disabilities, ELLs, and other groups.

Want to learn more? Suspension and expulsion rates for every school district can be found at http://ocrdata.ed.gov/DistrictSchoolSearch and further data analysis can be found at https://www2.ed.gov/policy/gen/guid/school-discipline/data.html