2004 SMART BRFSS MMSA Methodology

2004 Selected Metropolitan/Micropolitan Area Risk Trends from the BRFSS 
Creation of Metropolitan-level weights methodology

The Behavioral Risk Factor Surveillance System (BRFSS) Selected Metropolitan/Micropolitan Area Risk Trends (SMART) is a documented and verified subset of the 2004 BRFSS, which has been produced to provide some local area estimates.  These local areas are identified as metropolitan or micropolitan statistical areas (MMSA) as defined by the Office of Management and Budget.  The data set was produced by adding new analysis weights designed to correspond to the 2004 population estimates for each eligible MMSA.  The additional weights were post-stratified to the MMSA-level. The process by which these new weights were obtained is detailed in Appendix C, “Weight Class Collapsing Rules.”

Selected Areas 

Typically, BRFSS data are used to produce state-level estimates.  However, for the SMART project, BRFSS data were used to produce small area-level estimates for MMSAs as defined by the Bureau of the Census.  On June 6, 2003, the Office of Management and Budget (OMB) issued new definitions for metropolitan statistical areas, micropolitan statistical areas, and metropolitan divisions.  OMB periodically updates the list of MMSAs.  The list of areas used for this analysis can be found at http://www.whitehouse.gov/omb/bulletins/fy05/b05-02_appendix.pdf.  For more information about MMSAs, please visit http://www.census.gov/population/www/estimates/metroarea.html.  A respondent was associated with a particular MMSA on the basis of their county code.  Missing county codes were imputed from a value included in the purchased telephone sample that represents the county most likely associated with the telephone number.  MMSA-level estimates have been produced from the BRFSS data for 134 MMSAs that have met the weighting criteria (Appendix C) for the 2004 data year.

Appendix A: List of Variables added to the 2004 Data

Data Documentation for the 9 Variables Added to the 2004 BRFSS Data

ADJMMSA – MMSA-level post-stratification weight.  This factor is multiplied by the design weight (_WT2) to get the final MMSA-level weight (_MMSAWT).  

AGE_MMSA– age categories used to set up the initial weighting classes for the MMSA-level weights.  
	1 – 18–24 
	2 – 25–34 
	3 – 35–44 
	4 – 45–54 
	5 – 55–64 
	6 – 65+    

AGE_M_F – age categories used in the final weighting classes for the MMSA-level weights. 
	1 – 18–24 
	2 – 25–34 
	3 – 35–44 
	4 – 45–54 
	5 – 55–64 
	6 – 65+    
	7 – 18–34 
	8 – 35–54 
	9 – 55+    
	10 – 18–44
	11 – 45+
	12 – 18–54
	19 – 35+

RACE_MMS – 	race categories used to set up the initial weighting classes for the mmsa-level weights.  
	0 – Race not used 
	1 – White, non-Hispanic 
	2 – Nonwhite or Hispanic 

RACE_M_F – race categories used in the final weighting classes for the MMSA-level weights.  
	0 – Race not used 
	1 – White, non-Hispanic 
	2 – Nonwhite or Hispanic 

SEX_MMSA – sex categories used to set up the initial and final weighting classes for the MMSA-level weights (weight classes are never collapsed across sex).  
	1 – Male 
	2 – Female 

_MMSA – MMSA code of the metropolitan, micropolitan statistical area, or metropolitan division if appropriate, where the respondent lives.  Metropolitan and micropolitan statistical areas and metropolitan divisions are defined by OMB in Bulletin No. 03-04 (http://www.whitehouse.gov/omb/bulletins/b03-04_attach.pdf). 

_MMSANAM – MMSA name of the metropolitan/micropolitan statistical area, or metropolitan division if appropriate, where the respondent lives.  Metropolitan/micropolitan statistical areas and metropolitan divisions are defined by OMB in Bulletin No. 03-04 (http://www.whitehouse.gov/omb/bulletins/b03-04_attach.pdf).  

_MMSAWT – the new MMSA-level weight.  This is the weight to use when generating MMSA-level estimates (metropolitan or micropolitan statistical areas or metropolitan divisions) for questions that were asked of the whole sample.  

Appendix B: List of the 134 MMSAs that have MMSA-level Weights in 2004 BRFSS Data

Metropolitan/Micropolitan Statistical Area or Metropolitan Division Codes and Names

10420	Akron, OH Metropolitan Statistical Area	
10740	Albuquerque, NM Metropolitan Statistical Area	
10780	Alexandria, LA Metropolitan Statistical Area	
10900	Allentown-Bethlehem-Easton, PA-NJ Metropolitan Statistical Area	
11260	Anchorage, AK Metropolitan Statistical Area	
11700	Asheville, NC Metropolitan Statistical Area	
12060	Atlanta-Sandy Springs-Marietta, GA Metropolitan Statistical Area	
12260	Augusta-Richmond County, GA-SC Metropolitan Statistical Area	
12420	Austin-Round Rock, TX Metropolitan Statistical Area	
12580	Baltimore-Towson, MD Metropolitan Statistical Area	
12740	Barre, VT Micropolitan Statistical Area	
12940	Baton Rouge, LA Metropolitan Statistical Area	
13644	Bethesda-Frederick-Gaithersburg, MD Metropolitan Division	
13740	Billings, MT Metropolitan Statistical Area	
13820	Birmingham-Hoover, AL Metropolitan Statistical Area	
14260	Boise City-Nampa, ID Metropolitan Statistical Area	
14484	Boston-Quincy, MA Metropolitan Division	
14740	Bremerton-Silverdale, WA Metropolitan Statistical Area	
14860	Bridgeport-Stamford-Norwalk, CT Metropolitan Statistical Area	
15540	Burlington-South Burlington, VT Metropolitan Statistical Area	
15764	Cambridge-Newton-Framingham, MA Metropolitan Division	
15804	Camden, NJ Metropolitan Division	
16220	Casper, WY Metropolitan Statistical Area	
16620	Charleston, WV Metropolitan Statistical Area	
16700	Charleston-North Charleston, SC Metropolitan Statistical Area	
16740	Charlotte-Gastonia-Concord, NC-SC Metropolitan Statistical Area	
16940	Cheyenne, WY Metropolitan Statistical Area	
16980	Chicago-Naperville-Joliet, IL-IN-WI Metropolitan Statistical Area	
17140	Cincinnati-Middletown, OH-KY-IN Metropolitan Statistical Area	
17300	Clarksville, TN-KY Metropolitan Statistical Area	
17460	Cleveland-Elyria-Mentor, OH Metropolitan Statistical Area	
17820	Colorado Springs, CO Metropolitan Statistical Area	
17900	Columbia, SC Metropolitan Statistical Area	
18140	Columbus, OH Metropolitan Statistical Area	
18180	Concord, NH Metropolitan Statistical Area	
19124	Dallas-Plano-Irving, TX Metropolitan Division	
19380	Dayton, OH Metropolitan Statistical Area	
19740	Denver-Aurora, CO Metropolitan Statistical Area	
19780	Des Moines, IA Metropolitan Statistical Area	
19804	Detroit-Livonia-Dearborn, MI Metropolitan Division	
20100	Dover, DE Metropolitan Statistical Area	
20500	Durham, NC Metropolitan Statistical Area	
20764	Edison, NJ Metropolitan Division	
21340	El Paso, TX Metropolitan Statistical Area	
21604	Essex County, MA Metropolitan Division	
21820	Fairbanks, AK Metropolitan Statistical Area	
22020	Fargo, ND-MN Metropolitan Statistical Area	
22140	Farmington, NM Metropolitan Statistical Area	
22180	Fayetteville, NC Metropolitan Statistical Area	
22220	Fayetteville-Springdale-Rogers, AR-MO Metropolitan Statistical Area	
23104	Fort Worth-Arlington, TX Metropolitan Division	
24660	Greensboro-High Point, NC Metropolitan Statistical Area	
24860	Greenville, SC Metropolitan Statistical Area	
25540	Hartford-West Hartford-East Hartford, CT Metropolitan Statistical Area	
25860	Hickory-Lenoir-Morganton, NC Metropolitan Statistical Area	
26380	Houma-Bayou Cane-Thibodaux, LA Metropolitan Statistical Area	
26420	Houston-Baytown-Sugar Land, TX Metropolitan Statistical Area	
26580	Huntington-Ashland, WV-KY-OH Metropolitan Statistical Area	
26900	Indianapolis, IN Metropolitan Statistical Area	
27140	Jackson, MS Metropolitan Statistical Area	
28140	Kansas City, MO-KS Metropolitan Statistical Area	
28420	Kennewick-Richland-Pasco, WA Metropolitan Statistical Area	
28940	Knoxville, TN Metropolitan Statistical Area	
29340	Lake Charles, LA Metropolitan Statistical Area	
29740	Las Cruces, NM Metropolitan Statistical Area	
29820	Las Vegas-Paradise, NV Metropolitan Statistical Area	
30100	Lebanon, NH-VT Metropolitan Statistical Area	
30300	Lewiston, ID-WA Metropolitan Statistical Area	
30700	Lincoln, NE Metropolitan Statistical Area	
30780	Little Rock-North Little Rock, AR Metropolitan Statistical Area	
31084	Los Angeles-Long Beach-Glendale, CA Metropolitan Division	
31140	Louisville, KY-IN Metropolitan Statistical Area	
31700	Manchester-Nashua, NH Metropolitan Statistical Area	
32820	Memphis, TN-MS-AR Metropolitan Statistical Area	
33100	Miami-Fort Lauderdale-Miami Beach, FL Metropolitan Statistical Area	
33340	Milwaukee-Waukesha-West Allis, WI Metropolitan Statistical Area	
33460	Minneapolis-St. Paul-Bloomington, MN-WI Metropolitan Statistical Area	
33740	Monroe, LA Metropolitan Statistical Area	
34980	Nashville-Davidson-Murfreesboro, TN Metropolitan Statistical Area	
35004	Nassau-Suffolk, NY Metropolitan Division	
35084	Newark-Union, NJ-PA Metropolitan Division	
35300	New Haven-Milford, CT Metropolitan Statistical Area	
35380	New Orleans-Metairie-Kenner, LA Metropolitan Statistical Area	
35644	New York-Wayne-White Plains, NY-NJ Metropolitan Division	
35980	Norwich-New London, CT Metropolitan Statistical Area	
36260	Ogden-Clearfield, UT Metropolitan Statistical Area	
36420	Oklahoma City, OK Metropolitan Statistical Area	
36500	Olympia, WA Metropolitan Statistical Area	
36540	Omaha-Council Bluffs, NE-IA Metropolitan Statistical Area	
36740	Orlando-Kissimmee, FL Metropolitan Statistical Area	
37964	Philadelphia, PA Metropolitan Division	
38060	Phoenix-Mesa-Scottsdale, AZ Metropolitan Statistical Area	
38300	Pittsburgh, PA Metropolitan Statistical Area	
38860	Portland-South Portland, ME Metropolitan Statistical Area	
38900	Portland-Vancouver-Beaverton, OR-WA Metropolitan Statistical Area	
39300	Providence-New Bedford-Fall River, RI-MA Metropolitan Statistical Area	
39340	Provo-Orem, UT Metropolitan Statistical Area	
39580	Raleigh-Cary, NC Metropolitan Statistical Area	
39660	Rapid City, SD Metropolitan Statistical Area	
39900	Reno-Sparks, NV Metropolitan Statistical Area	
40060	Richmond, VA Metropolitan Statistical Area	
40484	Rockingham County-Strafford County, NH Metropolitan Division	
40860	Rutland, VT Micropolitan Statistical Area	
41180	St. Louis, MO-IL Metropolitan Statistical Area	
41620	Salt Lake City, UT Metropolitan Statistical Area	
41700	San Antonio, TX Metropolitan Statistical Area	
41860	San Francisco-Oakland-Fremont, CA Metropolitan Statistical Area	
42140	Santa Fe, NM Metropolitan Statistical Area	
42420	Scottsbluff, NE Micropolitan Statistical Area	
42580	Seaford, DE Metropolitan Statistical Area	
42644	Seattle-Bellevue-Everett, WA Metropolitan Division	
43340	Shreveport-Bossier City, LA Metropolitan Statistical Area	
43620	Sioux Falls, SD Metropolitan Statistical Area	
44060	Spokane, WA Metropolitan Statistical Area	
44140	Springfield, MA Metropolitan Statistical Area	
45104	Tacoma, WA Metropolitan Division	
45300	Tampa-St. Petersburg-Clearwater, FL Metropolitan Statistical Area	
45780	Toledo, OH Metropolitan Statistical Area	
45820	Topeka, KS Metropolitan Statistical Area	
45940	Trenton-Ewing, NJ Metropolitan Statistical Area	
46060	Tucson, AZ Metropolitan Statistical Area	
46140	Tulsa, OK Metropolitan Statistical Area	
47260	Virginia Beach-Norfolk-Newport News, VA-NC Metropolitan Statistical Area	
47644	Warren-Farmington Hills-Troy, MI Metropolitan Division	
47894	Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Division	
48300	Wenatchee, WA Metropolitan Statistical Area	
48620	Wichita, KS Metropolitan Statistical Area	
48864	Wilmington, DE-MD-NJ Metropolitan Division	
48900	Wilmington, NC Metropolitan Statistical Area	
49180	Winston-Salem, NC Metropolitan Statistical Area	
49340	Worcester, MA Metropolitan Statistical Area	
49420	Yakima, WA Metropolitan Statistical Area	
49660	Youngstown-Warren-Boardman, OH-PA Metropolitan Statistical Area	
49740	Yuma, AZ Metropolitan Statistical Area	

Appendix C:  Weight Class Collapsing Rules

MMSA-level Weighting Methodology

On June 6, 2003, OMB issued new definitions for metropolitan statistical areas, micropolitan statistical areas, and metropolitan divisions. See (http://www.whitehouse.gov/omb/bulletins/b03-04_attach.pdf).  Respondents were assigned to an MMSA on the basis of their county codes.  Missing county codes were imputed from a value included in the purchased telephone sample that represents the county most likely associated with the telephone number before the respondent identifies a county during data collection.

All respondents in cities were then assigned to age, race, and sex categories.  If a respondent’s age was missing, it was imputed by using the variable _IMPAGE available in the BRFSS public-use 2004 data file.  If a respondent’s race was missing, it was imputed by using the majority race for the MMSA in which the respondent lives.  The six age categories were 18–24, 25–34, 35–44, 45–54, 55–64, and 65+.  The two race categories were white, non-Hispanic, and nonwhite or Hispanic.

Within each MMSA, respondents were assigned to weighting classes on the basis of the age, race, and sex categories described above.  Some states do not use race in post-stratification.  For the MMSA in states that do not use race, only the age and sex groups were used to set up weighting classes.  For the MMSA in states that do use race, all three groups were used to set up weighting classes.  For the MMSA that cross state lines, the post-stratification variables used by the state in which the majority of the MMSA’s population lives were used to set up weighting classes.  Thus, MMSA that use race had 24 initial weighting classes and MMSA that do not use race had 12 initial weighting classes.  

Weighting classes with fewer than 19 sample members were collapsed in accordance with the following rules:

1.	For those MMSA that used race in post-stratification, the race categories within a sex category collapse if at least 80% of the age categories in that race /sex cross-classification (i.e. 5 of 6 the age categories) have fewer than 19 members. In MMSA that used race to create the initial weighting classes, the number of weighting classes was thus reduced from 24 to 12 if race was collapsed for both sexes and from 24 to 18 if race was collapsed for only one sex.

2.	Collapse the two youngest age categories in any age/sex or age/sex/race weighing class if either contains fewer than 19 members.  Do the same for the two middle and the two oldest age categories in each remaining weighting class.

3.	If either of the age/sex or age/sex/race categories have fewer than 19 members, then the age categories were collapsed until there were 19 members in some combination of the age categories listed in the variable AGE_M_F.

4.	Do not collapse weighting classes across sex.

5.	Do not include an MMSA in the reweighting that still has weighting classes with fewer than 19 sample members after all collapsing rules have been applied. These MMSAs will be excluded from the 2004 SMART BRFSS.  

There were 134 MMSA that had at least 500 respondents in the 2004 BRFSS and at least 19 sample members in all final weighting classes.  See Appendix B in the Data Documentation for a list of these MMSA.  Only the respondents in these MMSA were given a MMSA-level weight.  To calculate the new MMSA-level weight, we applied a post-stratification adjustment factor to the design weight (_WT2) and created the adjustment factor by taking the ratio of the total population over the sum of the design weights for each weighting class within each MMSA.  The new MMSA-level weight (_MMSAWT) should be used to generate estimates in these 134 MMSA.

Example SUDAAN Code:

For example, suppose we want an estimate for the Atlanta-Sandy Springs-Marietta, GA Metropolitan Statistical Area (MMSA code = 12060).  Here’s SAS/SUDAAN code that could be used to do this:

proc sort data=xxxx;
by _STSTR _SEQNO;
run;

proc descript data=xxxx filetype=sas design=wr;
nest _STSTR _SEQNO / missunit;
weight _MMSAWT;
subpopn _MMSA=12060 / name=” Atlanta-Sandy Springs-Marietta, GA”;
var (your analysis variable);
catlevel (the level of your analysis variable for which you want an estimate);
run;