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        <TITLE>New Mexico Small Areas</TITLE>
        <CONTENT>
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        <ibis:include href="../../text/SmallArea.xml"/><br/><br/>
<!--            New Mexico Small Areas are 108 geographic areas across the state with population sizes that are just 
                large enough to calculate rates for selected health events (e.g., diabetes deaths, asthma hospitalization, 
                etc.). New Mexico small areas were based on population size, not land area. Most (95%) of the New Mexico 
                small areas range in population size from 9,000 to 30,000 persons. Some counties have multiple small areas 
                (Bernalillo County has 34 small areas within its boundaries). In other cases, whole counties (e.g., 
                Harding, Quay and De Baca Counties) were combined to create a single small area.
                
-->             
                Reporting of health data for New Mexico sub-state geographies has formerly consisted of 
                presentation of data at the county level. County-level presentation is problematic
                in New Mexico because of the large differences in county population sizes. Smaller counties 
                such as Harding and DeBaca (with 2010 U.S. Census estimated population sizes of 695 and 2,022,
                respectively)<a href="#Bib-1">1</a>, have unstable rates on most health measures, while health measures 
                calculated for Bernalillo County (2010 Census population estimate=662,564) lack meaning because the 
                population is large and diverse. 
                <br/><br/>
                
                The New Mexico Department of Health (NMDOH) decision to embark on the small area project was based on 
                the intense demand for health status information at the community level,<a href="#Bib-2">2</a> the 
                desire to study the associations between health inequity and place, and the belief that a standard 
                set of small areas would improve efficiency in production of community data reports and accumulation 
                of comparable community-level data across various public health indicators and datasets. 
                <br/><br/>      

                <table class="Contents">
                        <tr><td class="ContentsHeader">Contents</td></tr>
                        <tr><td>
                        <a href="#part1">Methodology</a><br/>
                        <span class="Indent"><a href="#part2">Small Area Reference Materials</a></span><br/>
                        <span class="Indent"><a href="#part3">Geocoding and Classification of Data to Small Areas</a></span><br/>
                        <span class="Indent"><a href="#part4">Population Estimates</a></span><br/>
                        <a href="#part5">Small Area Workgroup</a>
                        <br/><a href="#REF">References</a><br/>
                        </td></tr>
                </table><br/>
                
                        <a id="part1"/>
                        <br/>
                        <h1>Methodology</h1><br/>
                        
                        From May of 2009 through November 2011, a workgroup consisting of staff from NMDOH, UNM, 
                        and others has met to design a set of New Mexico "Small Areas" for data reporting. 
                        The following design criteria were developed and used by the group.<br/><br/>
                        
                        <h3>Table 1. Criteria for Design of New Mexico Small Areas</h3>
                        <div><ol>
                        <li>    Areas should allow calculation of stable rates. To achieve stability in the 
                                rates, a target minimum population of 10,000 was set (yielding a denominator 
                                of at least 50,000 person-years across five years).</li>
                        <li>    NM small area geographies should be meaningful to communities. Small area 
                                boundaries should follow community boundaries whenever possible, and small 
                                areas should be as small as possible. A target maximum population size was 
                                set at 30,000.</li>
                        <li>    NM small areas will have within-area homogeneity and between-area heterogeneity 
                                on health-relevant demographic characteristics (given that criterion #2 is met). 
                                The demographic characteristics considered were(<a href="#Bib-3">3</a>):
                                <div><ul>
                                <li>Percentage of persons of Hispanic origin</li>
                                <li>Percentage of persons age 65+</li>
                                <li>Percentage of persons with a 4-year college degree</li>
                                <li>Percentage of children under age 17 in poverty</li>
                                <li>Percentage of owner-occupied housing units</li>
                                </ul></div>
                                </li>
                        <li>    Numerators and denominators must be available at the census tract level to 
                                support the calculation of mortality and other rates. Small areas will be 
                                designed by combining census tracts.</li>
                        <li>    Absent other relevant considerations, a single area will not cross health 
                                region or county boundaries.</li>
                                
                        <br/><h4>Considerations for Presentation of Data by Small Areas:</h4>
                        
                        <li>    Adhere to the New Mexico DOH small numbers rules (to protect privacy).</li>
                        <li>    Combine up to five years of data to improve reliability of the estimates.</li>
                        <li>    Consider and communicate the likely impact of geocoding of numerator events 
                                to geographic features other than a complete, correct address.</li>
                        </ol></div><br/>
                        
                <p align="right"><a href="#TOP">Back to Top</a></p>
                        
                        The New Mexico "Small Areas" Workgroup reviewed research and considered methods for
                        defining small areas. All methods have advantages and disadvantages. For instance, ZIP
                        code boundaries are relatively easy to communicate, but the boundaries shift over time
                        and commercial marketing firms must be relied on to provide estimates of population size 
                        and other demographic characteristics.<br/><br/>

                        The group decided to develop the New Mexico Small Areas by aggregating census tracts using 
                        above criteria as a guide. In the 2010 decennial census, New Mexico has 499 reporting 
                        census tracts with an average population size of 4,127. All but two NM Small Areas
                        (<a href="#Bib-4">4</a>) were defined by combining adjacent census tracts. Demographic 
                        characteristics from the 2000 U.S. Decennial Census were examined to meet criterion #3. 
                        <br/><br/>

                        The process yielded 108 New Mexico small areas with population sizes ranging from 929  
                        (Area 99, Santa Fe County, State Penitentiary)(<a href="#Bib-5">5</a>) to 31,925 (Area 
                        35, Chaves County, Roswell, N.E.). The area average population size is 18,892, and the 
                        median is 17,982. Many of New Mexico's more urban counties had sufficient population to 
                        support multiple sub-county small areas. In rural areas of the state, all or parts of 
                        two or more counties were often combined to reach the minimum population target of 10,000. 
                        Five New Mexico counties, Cibola, Torrance, Socorro, Lincoln, and Luna counties, were 
                        designated as single-county small areas.
                        <br/><br/>

                <a id="part2"/>
                        <br/>
                        <h2>Small Area Reference Materials</h2>
                        
                        <h3>New Mexico Small Area Boundaries and Locations Map</h3>
                        <br/>
                        <img src="contentfile/image/resource/NMSmallArea/Statewide2.PNG"  
                        title="New Mexico Small Areas, Version 1.3.3" alt="New Mexico Small Area Map"/> 
                        <br/><br/>

        <!--            Please visit the <a href="contentfile/html/SareaMapArcGIS.html" alt="Small Area Reference Map" target="blank">Small Area Reference Map</a>. 
                        This is an interactive map of small areas showing where each area is located in New Mexico.
        -->             
                        <br/><br/>
                        <h3>Small Area Population Files</h3>
                        <ibis:SelectionsList class="ExtraWhiteSpace">
                                <SELECTIONS>
                                        <SELECTION>
                                                <TITLE>Small Area Population Data Query on NM-IBIS</TITLE>
                                                <DESCRIPTION>Custom queries of population data by small area, year, age, sex and race/ethnicity.</DESCRIPTION>
                                                <URL>query/selection/pop/_PopSelection.html</URL>
                                        </SELECTION>
                                        <SELECTION>
                                                <TITLE>Small Area Population Data Files</TITLE>
                                                <DESCRIPTION>Data files and codebook for Small Areas.</DESCRIPTION>
                                                <URL>resource/PopData.html</URL>
                                        </SELECTION>
                                </SELECTIONS>
                        </ibis:SelectionsList>
                        <br/>
                        <h3>Small Area Mapping Resources</h3>
                        <ibis:SelectionsList class="ExtraWhiteSpace">
                                <SELECTIONS>
        <!--                            <SELECTION>
                                                <TITLE>Small Area esri Files (.MPK file)</TITLE>
                                                <DESCRIPTION>Shape files used with ESRI ArcGIS.</DESCRIPTION>
                                                <URL>/contentfile/docs/PopData/SmallAreaV133.mpk</URL>
                                        </SELECTION>
        -->
                                        <SELECTION>
                                                <TITLE>NM Small-Area-to-Census-Tract Crosswalk and SAS Code (Excel file)</TITLE>
                                                <DESCRIPTION>Excel file matches up 2000 and 2010 U.S. Census Tracts with NM Small Areas. 
                                                                 SAS code creates and labels areas from 2000 and/or 2010 U.S. census tracts.</DESCRIPTION>
                                                <URL>/contentfile/docs/PopData/SArea134.xlsx</URL>
                                        </SELECTION>
                                </SELECTIONS>
                        </ibis:SelectionsList>

                <p align="right"><a href="#TOP">Back to Top</a></p>
                        <br/><br/>      
                        A decision was made to avoid using tribal geographies as a design factor in the 108 
                        small areas. That decision was based on the following considerations, 1) it is NMDOH 
                        policy to release tribal health data and results of analysis identified by tribe to 
                        only the tribe, and not release them publicly, 2) New Mexico census tracts did not always 
                        follow tribal area boundaries, and 3) the NMDOH tribal epidemiologist is able to provide 
                        tribes with tribe-specific data and analysis of results.
                        <br/><br/><br/>

                <a id="part3"/>
                        <br/>
                        <h2>Classification of Data Records to Small Areas</h2><br/>

                        Health event counts for a given New Mexico Small Area were derived by attempting to geocode 
                        the residential address of each decedent. Geocoding assigned each address an x and y 
                        coordinate that corresponded to the Earth's latitude and longitude. The accuracy and 
                        precision of the geocoding process depended on having a complete and correct address 
                        on every death certificate that could be matched uniquely to a standardized address 
                        in a geodatabase that provided the needed geographic coordinates. Death records such 
                        as P.O boxes or rural routes that could not be matched to a standardized address were 
                        geocoded with the most precise alternate geocode available. Often this was the geocode 
                        of a nearby intersection, or the geographic centroid of the ZIP code, populated place, 
                        or county referenced in the address. Certain conditions make it difficult to precisely 
                        geocode every death record, including:
                        <div><ul>
                        <li>Missing or incorrect street numbers</li>
                        <li>Missing, misspelled, or nonstandard street names</li>
                        <li>Use of a post office box only</li>
                        <li>Use of a rural route, highway contract route or general delivery address</li>
                        </ul></div>
                        <br/>
                        <br/>
                        
                        <div class="Note">
                                <img src="contentfile/image/resource/important_icon.gif" alt="important! icon" width="16" height="15" title="IMPORTANT!"/>
                                It is important to recognize that small areas with misclassified data records 
                                will yield calculated health event rates that are higher or lower than the actual  
                                rate in that area. The New Mexico Department of Health is currently evaluating 
                                the small area rates published on NM-IBIS for misclassification errors. Until that 
                                evaluation is complete, please use those rates with caution and include the following
                                caveat along with any report of your results:
                                <br/><br/>

                                <div class="Note">
                                        <ibis:include href="../../text/SmallAreaCaveat.xml"/>
                                        <!--    *****Important! Small Area Analysis Caveat:*****
                                                Birth and death counts for a given New Mexico Small Area were derived by geocoding the 
                                                residential address of each decedent. Geocoding assigned each address an x and y
                                                coordinate corresponding to the Earth's latitude and longitude. Geocoding accuracy
                                                depends on having complete and correct addresses. Birth and death certificates with 
                                                addresses such as P.O boxes or rural routes were geocoded with the closest coordinates 
                                                available, often the center of a town or zip code area. Assignment of data records to 
                                                an incorrect small area has likely resulted in small area counts and rates that are 
                                                higher or lower than they should be. Misclassification errors are more likely to occur 
                                                in rural areas of the state (where P.O. boxes and rural routes are more common), but may 
                                                have occurred in any of the 108 small areas. 
                                                For more information on the New Mexico Small Area Methodology, 
                                                please visit: http://ibis.health.state.nm.us/resource/SmallAreaMethods.html. -->
                                </div>
                        </div><br/>
                        
                <p align="right"><a href="#TOP">Back to Top</a></p>
                <a id="part4"/>
                        <br/>
                        <h2>Population Estimates</h2><br/>
                        
                        Computation of death rates for a small area requires a count of deaths (numerator) 
                        and a population estimate (denominator) for each area and time period. The use of U.S. 
                        Census tract boundaries to define our small areas was based in part on the need for 
                        consistent geographies in the numerator and denominator. Census tract population estimates 
                        by year, age, sex and race for 2010 U.S. Census geographies for the years 1990 to 2010 were 
                        calculated by the Geospatial and Population Studies program at the University of New Mexico.
                        (For more information on calculation of health event rates, please see the NM-IBIS page
                        on <a href="resource/Rate.html">Health Event Rates</a>.)
                        <br/><br/>
                        
                <a id="part5"/>
                        <br/>
                        <h1>New Mexico Department of Health Small Area Workgroup</h1><br/>
                        The New Mexico Small Area Workgroup met from May of 2009 through November 2011 to design the New 
                        Mexico Small Areas and Small Area Methodology. <br/><br/>
                        
                        <div class="Indent">
                                Will Athas - UNM, Family &amp; Community Medicine<br/>
                                Alexis  Avery - DOH, PHD, Family Health Services Bureau<br/>
                                Jack Baker - UNM, Bureau of Business and Economic Research<br/>
                                Paige Best - DOH, ERD, Community Health Assessment Program<br/>
                                David Broudy - DOH, Metro/Northwest Health Region<br/>
                                Camille Clifford - DOH, Bureau of Vital Records and Health Statistics<br/>
                                Kate Daniel - DOH, Northeast Health Region<br/>
                                Janet Flores - DOH, Southwest Health Region<br/>
                                Lois Haggard - DOH, ERD, Community Health Assessment Program<br/>
                                Corazon Halasan - DOH, PHD, Diabetes Program<br/>
                                Wayne Honey - DOH, ERD, Injury and Behavioral Epi Bureau, Survey Unit<br/>
                                Heidi Krapfl - DOH, ERD, Environmental Epi Bureau<br/>
                                Michael Landen - DOH, ERD<br/>
                                Tracey Luna - DOH, Southeast Health Region<br/>
                                Jerry Montoya - DOH, Metro/Northwest Health Region<br/>
                                Larry Nielsen - DOH, Bureau of Vital Records and Health Statistics<br/>
                                Srikanth Paladugu - Bernalillo County<br/>
                                Jim Roeber - DOH, Injury and Behavioral Epi Bureau, Substance Use Epidemiology Section<br/>
                                Tom Scharmen - DOH, Metro/Northwest Health Region<br/>
                                Karen Scherzinger - UNM, Institute for Public Health<br/>
                                Barbara Toth - DOH, ERD, Environmental Epi Bureau, EPHT Program<br/>
                        </div>
                
                <br/><br/>
                <div>
                <a id="REF"/>
                <br/><p class="HRLeft"/>
                <h2>References</h2>
                <br/>   

                <a name="Bib-1"></a>1. U.S. Census Population estimates downloaded from <a href="http://quickfacts.census.gov">
                http://quickfacts.census.gov</a> on 10/27/2011.<br/><br/>
                
                <a name="Bib-2"></a>2. Bernalillo County Community Health Council: Health Data. 
                Downloaded from <a href="http://www.berncohealthcouncil.org/health-data">http://www.berncohealthcouncil.org/health-data</a> 
                on 11/1/2011.<br/><br/>
                
                <a name="Bib-3"></a>3. The five demographic characteristics were selected based on analysis 
                performed by the Utah Department of Health suggesting that these characteristics were representative 
                of a larger set of demographic characteristics that were strongly associated with a variety of health 
                outcomes.<br/><br/>
                
                <a name="Bib-4"></a>4. Area 9, Military bases, is spread across Bernalillo, Curry, Dona Ana, and Otero 
                Counties. Area 93 is a bow-tie-shaped area in Santa Fe County that has two almost contiguous parts.<br/><br/>
                
                <a name="Bib-5"></a>5. Area 100, Santa Fe County, State Penitentiary, is more of a "carve-out" to improve 
                the representativeness of data for the surrounding area, 99 - Santa Fe County, South.<br/><br/>
                
                <a name="Bib-6"></a>6. Scharmen, Thomas (2011) An Inventory of Address Variables in 18 Years of Birth 
                and Death Records. Presented at the October 5, 2011 meeting of the New Mexico Department of Health 
                Small Area Workgroup.<br/><br/>
                </div>

                <br/><br/><br/> 
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<!--
Will Athas - UNM, Family & Community Medicine
Alexis  Avery - DOH, PHD, Family Health Services Bureau
Jack Baker - UNM, Bureau of Business and Economic Research
Paige Best - DOH, ERD, Community Health Assessment Program
David Broudy - DOH, Region 1,3
Camille Clifford - DOH, Bureau of Vital Records and Health Statistics
Kate Daniel - DOH, Region 2
Janet Flores - DOH, Region 5
Corazon Halasan - DOH, PHD, Diabetes Program
Wayne Honey - DOH, ERD, Injury and Behavioral Epi Bureau, Survey Unit
Heidi Krapfl - DOH, ERD, Environmental Epi Bureau
Michael Landen - DOH, ERD
Tracey Luna - DOH, Region 4
Jerry Montoya - DOH, Region 1,3
Larry Nielsen - DOH, Bureau of Vital Records and Health Statistics
Srikanth Paladugu - Bernalillo County 
Jim Roeber - DOH, Injury and Behavioral Epi Bureau, Substance Use Epidemiology Section
Tom Scharmen - DOH, Region 1,3
Karen Scherzinger - UNM, Institute for Public Health
Barbara Toth - DOH, ERD, Environmental Epi Bureau, EPHT Program
-->