Growing Healthy Kids in Kentucky November 5, 2003 You Do the Math! How to Collect BMI for Your School Growing Healthy Kids in Kentucky November 5, 2003

Presenters Camille Powell & Nancy Hiner Lexington-Fayette County Health Department Teri Wood Kentucky Department for Public Health Cheri Tolle UK Prevention Research Center

Why collect BMI data? Address obesity epidemic at its roots Provide baseline data at local level Determine the extent of the problem Make evidence-based decisions Target high-risk schools/districts

Why collect BMI data? Respond to trends Compare with regional and national data Educate students, teachers, parents, administrators, community members, media

Confidentiality Consult with your employer’s privacy officer or person responsible for approving evaluation/data collection Obtain permission from the county superintendent’s office and principals for each school

What about HIPAA?

Fe Fi Fo FERPA… Family Educational Rights and Privacy Act Protects student records from being released to third parties Exception — organizations conducting studies on behalf of the schools http://www.ed.gov/policy/gen/guid/fpco/ferpa/index.html

How do you get in the door? Enlist support from the district’s central office Obtain written permission from superintendent’s office Enlist support from each school to gather the data Meet with the principal or vice principal, school nurse, family resource center coordinator, or other staff Have dst staff send letter to each school In some cases the Vice Principal or other administrative staff can give the okay, just be sure the principal is informed

How do you get in the door? Offer a monetary incentive if possible Promise to report back with findings and provide support

How do you get in the door? Contact other agencies that have gathered data to learn their strategies Barren River District Health Department Fayette County Health Department

How do you get in the door? Don’t approach schools about data collection during chaotic times of the year Beginning or end of the school year

Collection forms Gender Race Month/year of birth Height Weight Date of exam Other data (i.e., immunization)

What do you do with the collected information? Keep each school’s information confidential Compile a district report Compile individual school reports Compare individual school data with district data – do not report comparisons among schools

What to do with the collected information? Use data to support environmental and policy changes Use data for selecting program activities Use data for grant writing purposes Thank participating schools

Why size matters When randomness is a good thing What sample size will you want or need? Do you want to look at schools or districts? Having decided on 1 and 2 above, how do you draw a random sample?

Deciding sample size How much error are you willing to accept in your study? What time/money or other resource limits do you face? What level of analysis are you interested in? District School

How does level of analysis affect sample size? Examples of differing sample sizes for different size populations 800 6th graders in the district Sample size = 260 200 6th graders in each of 4 schools Sample size – 132 for each school Total of 528

How to select a random sample Decide on your sample size Do a systematic random sample Calculate a SAMPLING INTERVAL by dividing the population size by the sample size: Sampling interval = population size/sample size 3=800/260 This means you select every third record until you have completed 260 records

How to select a random sample Select the first record by using the random number chart (in handout) Use your sampling interval number to select the remaining records

Lessons learned Race Age Date of data May be coded as a number Often found on “attendance report” or class list Age Only record month and year because of FERPA regulations Date of data “Old” data may need to be thrown out

Lessons learned Not having enough kids with records to complete the sample size Obtain accurate class sizes Charts being grouped with multiple grades If more than 20% of records are incomplete, BMI data is not valid

Lessons learned Charts in transition during summer break Forgetting to start with random number