Mississippi Behavioral Risk Factor Surveillance System (BRFSS)

Introduction

It is generally acknowledged by health care professionals that certain behavior patterns are associated with disease, injury and death. Among these are cigarette smoking, physical inactivity, excessive weight gain, unhealthy diet, and excess alcohol consumption. The Behavioral Risk Factor Surveillance System (BRFSS) is a program designed to estimate the prevalence of these and other health risk factors in each state. The results provide a tool for evaluating health trends, assessing the risk of chronic disease, and measuring the effectiveness of policies, programs and awareness campaigns.

Methodology

A. Sampling design

The Mississippi BRFSS is a random sample telephone survey of the adult (18 years of age and older) civilian non-institutionalized population in the state. Using a system of random digit dialing and Computer Assisted Telephone Interviewing (CATI), the survey has the potential to reach 93% of all households in Mississippi (i.e., those that have telephones according to South Central Bell data). The survey is conducted on an ongoing basis throughout the year. A sample size of between approximately 4,000 and 5,000 persons is selected each year to give a 95% confidence interval of ±3% or less on risk factor prevalence estimates of the adult population.

Interviewers, contracted by the MSDH, contact residences during weekdays between 9:00 a.m. and 9:00 p.m. and Saturdays between 8:30 a.m. and 4:30 p.m. After a residence had been contacted, one adult (18 years of age or older) is randomly selected to be interviewed from all adults residing in the household. Interviews are conducted during a two-week period each month. The response rate for the survey is greater than 90%.

B. Questionnaire

The questionnaire, designed through cooperative agreements with the CDC, contains questions from three categories. The first category contains questions on health status, access to health care, health awareness, health risk behaviors, and preventive health; the second contains demographic information (age, sex, race/ethnicity, education, annual household income, and employment status); and the third contains questions addressing specific issues that are of particular interest to the state conducting the survey.

Limitations of the Data

Although BRFSS data are self-reported, the validity and reliability of this method of surveillance have been well established for many chronic diseases and risk behaviors. All data collection systems are subject to error, and records may be incomplete or contain inaccurate information. People may not remember essential information, a question may not mean the same thing to different respondents, and some individuals may not respond at all. It is not always possible to measure the magnitude of these errors or their impact on the data. The user must make his or her own evaluation of the data.

C. Data analysis

The data are sent to CDC editing, weighting, and analysis; further analysis is done by the MSDH Office of Public Health Statistics and Office of Community Health Services. The weighting factor takes into account the probability of selection into the sample and the age/race/sex distribution of the general population (based on the projected Mississippi population for that year). The estimates are considered representative of all adults in Mississippi who have telephones.