Introduction
Approximately 70% of all deaths in the United States are due to chronic health conditions. A majority of these chronic health conditions are due to behaviors of individuals that can be improved. Sustainable improvement in health outcomes for the majority of the population requires improvement in healthy behaviors. Efforts to improve the community's health depend of the measurement of outcomes and behaviors in order to develop strategies for intervention at the community level.
Health outcomes can be measured by reviewing medical and vital records, such as birth certificates and death certificates. Measuring the behaviors that have such a profound impact on health requires either observing what people do or asking them what they do. The BRFSS is the primary source of data for local entities, states, and the nation on the health-related behaviors of adults. States collect data through monthly telephone interviews with non-institutionalized adults aged 18 years or older. BRFSS interviewers call both landlines and cell phones and ask respondents questions related to behaviors that are associated with preventable chronic diseases, injuries, and infectious diseases.
Lancaster County BRFSS
The Lancaster County Behavioral Risk Factor Surveillance System (BRFSS) has been conducting surveys annually since 1989 for the purpose of collecting data on the prevalence of major health risk factors among adults residing in Lancaster County. Information gathered in these surveys can be used to target health education and risk reduction activities throughout the county in order to lower rates of premature death and disability.
The surveillance system is based on a research design developed by the Centers for Disease Control and Prevention (CDC) and used in all 50 states, the District of Columbia, and three U.S. territories. Questions are standardized to ensure comparability of data with other states and to allow determination of trends over time.
The Data Collection
The BRFSS gathers information through telephone surveys conducted by the health departments of all 50 states, the District of Columbia, Guam, Puerto Rico, and the U.S. Virgin Islands, with help from CDC. Since 2011, even cell phones are used to gather the surveillance data. The BRFSS is the world's largest continuously conducted telephone health surveillance system, which conducts more than 400,000 interviews per year.
Changes in New Weighting Methodologies
Refinements to the Behavioral Risk Factor Surveillance System (BRFSS) to include data received from cell phone users facilitates the inclusion of a broader demographic and ultimately provides a better reflection of the nation's health status.
The BRFSS telephone survey has been traditionally done with people using landline telephones. However, in recent years, an increasing number of people are only using cell/mobile phones. CDC recognized the need to include cell phone users in the survey in order to obtain data that better represents the diverse populations in our society (nation). Because of the expanded and improved way we gather and process information, new data cannot be accurately compared to previous findings line by line (point by point). However, as we move forward, the survey results will better reflect the health status of the people of the county, state and nation.
In the past few years, all large population health surveys that depend on telephone interviews, including the Behavioral Risk Factor Surveillance System (BRFSS), have had to respond to the rapid rise in the proportion of U.S. households that contain only cellular telephones and no landline telephones. In order to maintain survey coverage and validity, surveys have had to add cellular telephones to their samples. At the same time, new methods of weighting to adjust survey data for differences between the demographic characteristics of respondents and the target population have been adopted.
Since 2004, the BRFSS has been planning and testing the addition of cellular telephones and improvements in its method of statistical weighting. These new methods were implemented during the fielding of the 2011 BRFSS, which were released in 2012. This policy note describes the methodological changes and their potential effects on BRFSS prevalence estimates. Policy makers who use BRFSS estimates for decision making should be aware of the new methods and their potential effects on estimates. Careful planning in communicating the impact of changes in methods on estimates to non-scientific audiences is needed to prevent misinterpretation.
Source: Above description (language) on "Methodologic Changes in the Behavioral Risk Factor Surveillance System in 2011 and Potential Effects on Prevalence Estimates" is provided to the state and local BRFSS programs through the factsheet titled "Behavioral Risk Factor Surveillance System Improving Survey Methodology" prepared by the Public Health Surveillance Program Office and Division of Behavioral Surveillance, Office of Surveillance, Epidemiology and Laboratory Services, Centers of Disease Control and Prevention.