Presentation on theme: "Behavioral Risk Factor Surveillance System (BRFSS) Contributors: Wayne A. Honey, MPH Jennifer E. Daniel, MPH Annie Hickman, BS Survey Unit, Injury & Behavioral."— Presentation transcript:
Behavioral Risk Factor Surveillance System (BRFSS) Contributors: Wayne A. Honey, MPH Jennifer E. Daniel, MPH Annie Hickman, BS Survey Unit, Injury & Behavioral Epidemiology Bureau Epidemiology & Response Division, NM Department of Health December 8, 2004
BRFSS - Objectives n Determine priority health issues & populations at highest risk for illness, disability, and death. n Support development of strategic plans n Target prevention programs n Educate the public, the health community, and policy makers about disease prevention.
BRFSS - Objectives Support community policies that promote health and prevent disease. n Monitor the effectiveness of interventions and progress in meeting prevention goals (limited).
BRFSS – Applications (Examples on following slides) n Estimate: Prevalence & Distribution of Selected Diseases/Conditions n Estimate: Prevalence & Distribution of Risk Behaviors & Protective Factors n Comparison to HP2000 & HP2010 n Monitor Trends
Breast Cancer Screening No Significant Difference (Other than 1991 & 1997) All Female Respondents Age 40+, excluding DK/NS, Refused, or missing.
Cervical Cancer Screening No Significant Difference (Other than 1997) Denominator includes all female survey respondents age 18 and older with uterine cervix except those with missing, don't know, and refused answers.
BRFSS – Applications (Examples on following slides) n Describe Associations Between Disease/Conditions & Risk Factors n Estimate: Prevalence of Health Care Coverage n Comparisons: State-to-State, State to Nation; sub- state areas n Estimate: Utilization of Preventive Screening
Associations Prevalence of Chronic Health Conditions*, by disability status 0 20 40 60 80 100 No disability Disability not requiring assistance Disability requiring assistance Arthritis (2000) Diabetes (1998-00) Hypertension (1999) Cardio- vascular disease (1998,99) Percent of group with condition Osteoporosis (1999) * Rates are age-adjusted by the direct method to the weighted age distribution of the NM BRFSS survey for the designated year or years.
Comparisons: State-to-State; State-to-Region; State-to-Nation Percentage of New Mexicans Without Health Care Coverage
Percentage of Women Not Screened for Breast CA. New Mexico, Region*, and U.S.**, 2000. * Region: Arizona, Colorado, Utah, Oklahoma, and Texas. ** 50 states, plus the District of Columbia and Puerto Rico. Source: U.S. BRFSS, 2000.
Percentage of Women Age 40 and Older Who Have Never Had a Mammogram, by Education. New Mexico, 2000.
Percentage of Women Age 40 and Older Who Have Never Had a Mammogram, by Household Income. New Mexico, 2000.
Percentage of Women Not Screened for Cervical CA. New Mexico, Region*, and U.S.**, 2000. * Region: Arizona, Colorado, Utah, Oklahoma, and Texas. ** 50 states, plus the District of Columbia and Puerto Rico. Source: U.S. BRFSS, 2000.
Percentage of Women Who Never Had a Pap Smear, by Household Income. New Mexico, 2000. Household Income
BRFSS - Methodology n Telephone Survey Methods n On going Survey of Adults n Random Selection of Household n Random Selection of One Adult (>= 18 Yrs.) Per Household n Computer-Aided Telephone Interviewing (CATI) System
Disproportionate Stratified Sample Genesys, Inc. creates blocks of 100 #’s with same area code, prefix, 2 digit suffix: (505) 662-2600 thru (505) 662-2699 Compare to List of all possible #’s. Group into following 2 Blocks: Not-listed 1+ Block #’s Listed #’s Sampled at 1.5:1 of Not-Listed 1+ Block #’s Zero Block Not sampled since 2002 Replicates of 50 Random #’s Each Replicate is a Disproportionate Stratified Sample
NM BRFSS Sample Geographic Stratification* Stratified since 2001 2004 Sample Size = 6,430 Sample Per Stratum = 1,286 DSS Design Replicated in each stratum. 2004: 6 th Stratum over- sampling Native Americans *County assignment to strata will change in 2006 to match new Public Health Districts.
Disproportionate Stratified Sample Purchase lists of randomly generated phone numbers from which known business and non-working numbers have been eliminated Dial one number If residence, determine eligibility of household (at least one adult 18 or older). If not eligible, stop If eligible, randomly select one adult 18 or older for the interview. If no answer, redial up to 15 times. If non-residence or non-working, stop.
BRFSS - Strengths n State & Sub-state Estimates n State Control n Timeliness n Reasonable Reliability & Validity (with caveats) n Efficiency (Cost) n Effective Monitoring of Data Collection
BRFSS - Weaknesses n Validity (Self-report) n Reliability (Select Variables or small sample size) n Refusal Rates higher than Face-to-Face, and Increasing n Exclusion of non-telephone HH n Exclusion of Cell Phones
Accessing BRFSS Data n Submit requests to email@example.com@doh.state.nm.us Tables, charts, brief reports, or data files n On-Line NM BRFSS Reports: www.health.state.nm.uswww.health.state.nm.us Click on Health Data tab Click on Health Behaviors Click on Adult Click on report of choice n CDC BRFSS : www.cdc.gov\brfsswww.cdc.gov\brfss Click on Prevalence Data or Trends Data hot keys
BRFSS - Weighting Probability of Selection FINALWT = STRWT * 1 OVER NPH * NAD * POSTSTRAT FINALWT is the final weight assigned to each respondent. STRWT accounts for differences in the basic probability of selection among strata (subsets of area code/prefix combinations). It is the inverse of the sampling fraction of each stratum. There is seldom a complete correspondence between strata, which are defined by subsets of area code/prefix combinations, and regions, which are defined by the boundaries of government entities.
BRFSS - Weighting Probability of Selection FINALWT = STRWT * 1 OVER NPH * NAD * POSTSTRAT 1/NPH is the inverse of the number of residential telephone numbers in the respondent’s household. NAD is the number of adults in the respondent’s household.
BRFSS - Weighting Probability of Selection FINALWT = STRWT * 1 OVER NPH * NAD * POSTSTRAT n POSTSTRAT is the number of people in an age-by-sex or age-by-race/ethnicity-by-sex category in the population of a region or a state divided by the sum of the preceding weights for the respondents in the same age-by-sex or age-by-race/ethnicity-by-sex category. It adjusts for non-coverage and non-response and forces the sum of the weighted frequencies to equal population estimates for the region or state.