methods for evaluating within-state variations using the national survey of children with special...
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Methods for Evaluating Within-State Variations Using the National Survey of
Children with Special Health Care NeedsVirginia Sharp
Center for Children with Special Needs
Center for Children with Special Needs
Overview
> Why bother?
> What sub-state geographic identifiers are
available in national surveys?
> What alternatives are available?
> Accessing the data
> Example of Rural-Urban differences in
access to care in Washington state
Center for Children with Special Needs
Why bother?
> Statewide summary measures do not accurately reflect conditions in any particular segment of the state and may mask significant local issues
> Health services are delivered locally
> Limited health service dollars require targeting programs to meet specific needs
> Local health jurisdictions need to be able to “see themselves” in the data.
Center for Children with Special Needs
Geographic Identifiers in SLAITS
> State
> MSA status– MSAs define metropolitan areas as a core area
with 50,000 or more inhabitants, such as a central city, along with the counties economically and socially connected to it
– MSAs are not static; both their definition and application change over time
Center for Children with Special Needs
Why not just use MSA Status?
> Not available for all states– Required edits to protect confidentiality result in
MSA status being suppressed whenever the total Census 2000 population of either the combined MSA counties or the combined non-MSA counties is less than 500,000 persons.
– 16 states affected in NS-CSHCN
Why not just use MSA Status?
Center for Children with Special Needs
Non-MSA population too small
MSA population too small
BOTH non-MSA & MSA populations too small
Suppressed MSA status in NS-CSHCN
Hawaii
Alaska
Center for Children with Special Needs
Why not just use MSA Status?
> Not available for all states> Too little variation within many states
– In Washington state, 85% of Census 2000 population in MSAs (12 counties)
– 2003 MSA definition adds 6 more counties, increasing to 89% of WA population in MSAs
Why not just use MSA Status?
Center for Children with Special Needs
SPO KANE
FRANKLIN
BENTO NYAKIMA
CLARK
THURSTO NPIERCE
KING
SNO HO MISH
W HATCO M
KITSAP
ASOTIN
DOUGLAS
CHELAN
SKAGIT
SKAM ANIA
COWLITZ
MSAs in Washington State, 1999
Center for Children with Special Needs
Why not just use MSA Status?
> Not available for all states> Too little variation within many states> Differences in county size obscure differences
across states– Yakima county, an MSA, is 4296 square miles
– State of Delaware is 2489 square miles
> Differences in county size obscure differences within states– Average population density in Yakima county was
51.8 persons per square mile
Why not just use MSA Status?
Center for Children with Special Needs
Rural Urban Commuting Area Codes
> Census-tract based classification scheme> Uses standard Bureau of the Census urban area
and place definitions in combination with commuting information
> Characterizes each census tract based on population density, urbanization & daily commuting
> Identifies urban core areas and adjacent territory that is economically integrated with those cores
Center for Children with Special Needs
Rural Urban Commuting Area Codes
> First developed from 1990 census data• Released for both census tracts & zip code delivery
areas
> Revised for 2000 decennial census• Census tract versions released March ‘05• Zip code versions coming soon
> Developed by UW Rural Health Research Center with funding from US Dept. of Agriculture, Economic Research Service
Center for Children with Special Needs
Why RUCAs?
> Flexibility– 10 primary codes– 30 secondary codes– Allows for selective combination of codes to
meet varying definitional needs
> Based on smaller geographic areas– Census tracts/zip areas vs. counties
> Consistent with OMB concepts of metropolitan and micropolitan areas
Center for Children with Special Needs
Zip Code RUCAs, Washington 2000
Urban Core
Suburban
Large Town
Small Town/Rural
Center for Children with Special Needs
Accessing RUCAs for NS-CSHCN
> Obtain zip code RUCAs for area of interest– http://www.ers.usda.gov/Data/
RuralUrbanCommutingAreaCodes/
> Submit proposal to NCHS Research Data Center– http://www.cdc.gov/nchs/r&d/rdc.htm
> Jump through the RDC’s hoops
Center for Children with Special Needs
RDC Decisions
> What specific survey files do you want to merge RUCA codes into?– $500 charge per file prepared by RDC
> On-site or Remote Access?– On-site:
• SAS, SUDAAN, STATA, Fortran• $200/day• Normal business hours• Output reviewed for disclosure issues
Center for Children with Special Needs
RDC Decisions
– Remote Access:• SAS programs only
– (certain procedures/functions not allowed)
• Submit programs via e-mail; results returned next day
• $500/month for any one data set
Center for Children with Special Needs
RDC Issues
> RDC is not “customer friendly”
> Processes not always clear
> If on-site, must allow sufficient time for RDC staff to review all output at end of day
> RDC staff do not provide consultation on surveys themselves or statistical analysis
> Must advocate for needs
Center for Children with Special Needs
Examples from Washington State
67.6%
15.9%
8.6% 7.9% 6.3%9.8%
15.0%
68.9%
0%
10%
20%
30%
40%
50%
60%
70%
80%
Urban Core Suburban Large Towns Small Towns& Isolated
Rural Areas
WASHINGTONCensus 2000Children <18 yrs
WASHINGTONNS-CSHCNInterview Sample
Sample Size
514
112 73 47
Center for Children with Special Needs
Needed Routine Preventive Care
80.8%72.7%62.5%77.0%
0%
20%
40%
60%
80%
100%
Urban Core Suburban Large Towns Small Towns &Isolated Rural
AreasStatewide mean = 74.6%
Center for Children with Special Needs
Needed Specialized Therapies
Statewide mean = 26.5%
27.6%
28.0%
15.9%
25.5%
0%
10%
20%
30%
40%
50%
Urban Core Suburban Large Towns Small Towns &Isolated Rural
Areas
Center for Children with Special Needs
Received All Needed Dental Care
91.6% 86.2% 75.3% 90.5%
0%
20%
40%
60%
80%
100%
Urban Core Suburban Large Towns Small Towns& Isolated
Rural AreasStatewide mean = 89.5%
Center for Children with Special Needs
Received All Needed Mental Health Care
Statewide mean = 79.9%
80.9% 83.6% 66.7% 78.6%
0%
20%
40%
60%
80%
100%
Urban Core Suburban Large Towns Small Towns &Isolated Rural
Areas
Center for Children with Special Needs
Child has 2+ Unmet Health Needs
4.8% 7.3% 12.2% 4.0%
0%
5%
10%
15%
20%
25%
30%
Urban Core Suburban Large Towns Small Towns &Isolated Rural
AreasStatewide mean = 5.8%
Center for Children with Special Needs
Family has Unmet Service Needs
6.6% 10.9% 18.1% 7.6%
0%
10%
20%
30%
40%
Urban Core Suburban Large Towns Small Towns &Isolated Rural
AreasStatewide mean = 8.4%
Center for Children with Special Needs
Topics for Further Study
> Is statistical significance at the 95% confidence level necessary for within-state disparities to be important to public health agencies?
> How can these findings be used by MCH agencies to reduce geographic disparities?
> To what extent are within-state disparities in access to care for CSHCN a function of agency structure? Is there a “most efficient” structure for equitable access to CSHCN-related services?
> Would alternate rural-urban definitions yield the same or similar results?
Center for Children with Special Needs
Conclusions
> Within-state variation in access to care based on rural-urban setting for CSHCN can be significant
> Working through the Research Data Center at NCHS, analyses of within-state variation can be conducted on the NS-CSHCN & NS-CH
> These data cannot be used to identify issues in specific places within a state
> States interested in improving their ability to understand within-state patterns should invest in additional sample size in future surveys
Contact Information:[email protected]
(206) 987-5311Funding from the Washington State Department of Health, CSHCN Program
and an MCHB CSHCN Financing Grant supported this research.