Scientific Data Documentation
Behavioral Risk Factor Surveillance System (1989)
BRFS
ABSTRACT
The Behavioral Risk Factor Surveillance System (BRFSS) is an on-going
random-digit-dialed telephone survey used to determine the prevalence among
adults 18 and older of behaviors and practices--such as cigarette smoking,
seat belt use, blood cholesterol screening, high blood pressure control,
physical activity, weight control, alcohol use, and drinking and driving--
which are related to the leading causes of death in the US. To maximize
comparability, methods and questionnaires are standardized across partici-
pating states and over time. One-time surveys were conducted in 28 states
(including DC) between 1981 and 1983. On-going surveillance surveys were
conducted in 15 states in 1984, 22 states in 1985, 26 states in 1986, 34
states in 1987, 37 states in 1988, 40 states in 1989, and 45 states in 1990.
WONDER contains data from the 1989 surveys. In 1989 the median yearly sample
size for states was almost 1700. The results are weighted to take into
account the effects of telephone non-coverage, non-response, refusals,
sampling design, and to adjust the survey data to the age-, race-, or sex-
specific population counts from the most recent census or intercensal
estimate in each state.
BACKGROUND
During the 1960s and 1970s, the role of personal behaviors--such as cigarette
smoking, alcohol consumption, dietary habits, and physical inactivity--as
risk factors for disease became recognized. Accordingly, many state health
departments launched health education and risk reduction programs to reduce
the prevalence of behavioral risks in the population. State specific data
on which to plan or guide these efforts were, however, unavailable, unreli-
able, or prohibitively expensive. By 1980, telephone surveys had emerged as
both a reliable and affordable alternative method for determining the preva-
lence of behavioral risk factors in the population. Accordingly, the CDC
began working with state health departments to develop a system for the on-
going surveillance of behavioral risk factors in the population using random-
digit-dialed telephone techniques. The goal of the system was to collect,
analyze, and interpret state-specific behavioral risk factor data, in order
to plan, implement, and monitor public health programs.
From 1981 to 1983, random-digit-dialed one-time telephone surveys were
conducted in 29 states (including the District of Columbia) by state health
department personnel. These surveys were supported, in part, through funds
provided in the Health Education and Risk Reduction Grants, with the CDC
providing training, coordination and standard methods. Beginning in 1984,
the surveys have been conducted in a seven-to-ten day period every month
throughout the year, and have come to be known collectively as the Behavior-
al Risk Factor Surveillance System (BRFSS). The CDC continues to provide
training, coordination, and standard methods and, in addition, provides funds
directly to the participating state health departments through cooperative
agreements. The number of participating states has increased from 15 in
1984 to 22 in 1985, 26 in 1986, 34 in 1987, 37 in 1988, 40 in 1989, and 45 in
1990. Several state health departments have also conducted surveys using
the standard telephone survey methods and questionnaires without CDC funds.
Since 1981, 53 different states and territories have participated with the
CDC in the BRFSS.
In the BRFSS, respondents are selected randomly from adult civilian residents
with telephones. In most states, the telephone number is selected using a
multistage cluster design known as the Waksberg method. After a household is
contacted, an adult aged 18 years or older is randomly selected from among
the adults residing in the household and interviewed. If the adult selected
is not available, the interview is done during a follow-up telephone call.
To improve efficiency in contacting eligible respondents, the interviews are
conducted primarily weekday evenings, but also during the day and on
weekends. Beginning in 1985, most states began using computer assisted
telephone interviewing (CATI) to facilitate the interview, data coding and
entry, and quality control procedures.
The questionnaire used in Behavioral Risk Factor Surveillance has three
components: the core, standardized modules and state-added questions. The
core questions and the standardized modules are developed jointly by states
and CDC. For comparability, many of these questions have been selected from
national surveys, such as the National Health Interview Surveys and the
National Health and Nutrition Examination Surveys. All states are expected
to ask the core questions and may choose to add any or all of the standard-
ized modules. States with interests beyond the core and standardized mod-
ules may develop their own state-added questions. These questions are
attached at the end of the questionnaire in order to maintain comparability
between states and over time.
Upon completing the interviewing cycle each month, the data are keyed and
sent to CDC for editing. After editing, the data are weighted to provide
representative population-based estimates of risk factor prevalence
(accounting for telephone noncoverage, nonresponse, refusals, and the cluster
survey design). The weighted and unweighted tabulations are provided to the
states within six months of completion of the last December interview. In
addition, the CDC publishes the annual summary and selected risk-factor
specific reports throughout the year in the Morbidity and Mortality Weekly
Report
The information gathered under the BRFSS is expected to support risk reduc-
tion and disease prevention activities by state health departments.
Because comparable methods are used from state to state and from
year to year, states can compare risk factor prevalence with other states and
monitor the effects of interventions over time. Also, the use of consistent
methods in a large group of states permits the assessment of geographic
patterns of risk factor prevalence. These telephone survey techniques can
also be applied at the community level to guide local efforts in reducing
risk factor prevalence. Taken together, the behavioral risk factor survey
and surveillance data provide a new resource to guide state and local disease
prevention efforts.
The BRFSS is coordinated by the Behavioral Surveillance Branch (BSB), Office
of Surveillance and Analysis, National Center for Chronic Disease Prevention
and Health Promotion, CDC, Atlanta, Georgia. Information about the BRFSS
(including copies of BRFSS publications, presentations, or questionnaires)
can be obtained from the participating state health departments or from the
Behavioral Surveillance Branch.
RISK FACTOR DEFINITIONS
SEATBELT(1) RESPONDENTS REPORTING THEY "SELDOM" OR "NEVER"
USE SEATBELTS.
SEATBELT(2) RESPONDENTS REPORTING THEY "SOMETIMES", "SELDOM"
OR "NEVER" USE SEATBELTS.
THESE DATA ITEMS ARE CLOSER TO
VALIDATION STUDIES OF SEATBELT USAGE
THAN SEATBELT(1) I.E., _RFSEATB.
HYPERTENSION(1) RESPONDENTS WHO REPORT THEY HAVE NEVER BEEN
TOLD THEY ARE HYPERTENSIVE AND
THEIR BLOOD PRESSURE IS "STILL HIGH".
HYPERTENSION(2) RESPONDENTS WHO REPORT THEY HAVE NEVER BEEN
TOLD THEY ARE HYPERTENSIVE.
HYPERTENSION(3) RESPONDENTS WHO REPORT THEY HAVE BEEN TOLD THEIR
BLOOD PRESSURE IS HIGH MORE THAN ONCE,
OR ARE ON MEDICATION,
OR REPORT THEIR BLOOD PRESSURE IS STILL HIGH.
THIS DATA ITEM HAS BEEN ADDED TO DEFINE
"CURRENT HYPERTENSIVES",
A REFLECTION OF THE KNOWN, DIAGNOSED
HYPERTENSIVES IN THE POPULATION.
THIS IS THE NATIONAL HEART, LUNG AND BLOOD
INSTITUTES DEFINITION.
OVERWEIGHT (1) RESPONDENT AT OR ABOVE 120% OF IDEAL WEIGHT.
IDEAL WEIGHT DEFINED AS THE
MID-VALUE OF A MEDIAN FRAME PERSON FROM THE
1959 METROPOLITAN HEIGHT-WEIGHT TABLES.
OVERWEIGHT (2) FEMALES WITH BODY MASS INDEX
(WEIGHT IN KILOGRAMS DIVIDED BY HEIGHT
IN METERS SQUARED (W/H**2)) >=27.3
AND MALES WITH BODY MASS INDEX >=27.8
SMOKING CURRENT REGULAR SMOKER (EVER SMOKED 100
CIGARETTES AND SMOKE NOW).
ACUTE DRINKING RESPONDENTS WHO REPORT HAVING FIVE OR MORE
DRINKS ON AN OCCASION, ONE OR MORE
TIMES IN THE PAST MONTH.
DRINK/DRIVE RESPONDENTS WHO REPORT HAVING DRIVEN AFTER
HAVING TOO MUCH TO DRINK, ONE OR
MORE TIMES IN THE PAST MONTH.
CHRON. DRINKING RESPONDENTS WHO REPORT AN AVERAGE OF 60 OR
MORE ALCOHOLIC DRINKS A MONTH.
SEDENTARY LIFE RESPONDENTS AT SEDENTARY OR IRREGULAR
ACTIVITY LEVEL.
SURVEY BY STATE
