Are clusters of mental retardation correlated with clusters of developmental delay?

Zhen, Huiling and McDermott, Suzanne and Lawson, Andrew B. and Aelion , Marjorie (2009) Are clusters of mental retardation correlated with clusters of developmental delay? Geospatial health , 4 (1). pp. 17-26. ISSN 1970-7096

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Mental retardation (MR) is a subset of developmental delay (DD), a broader classification of childhood disability. The purpose of this study was to determine if clusters of these two conditions were statistically significantly correlated. The residential addresses of 81,935 Medicaid insured pregnant women during each month of pregnancy were used to identify clusters of MR and DD in their children. Correlations between MR and DD were computed based on the sets of P-value surface from selected centroid points, where the P-value for cumulative relative risk of MR and DD was known. The correlations are quite small for all the 10 gestational months for which maternal addresses were available, but they are all statistically significant. This indicates MR and DD are correlated, but they are not linear. When MR was used as the centroid point to identify a cluster the only correlations that were statistically significant were for gestational month 5 and 6 with correlation 0.14 (P = 0.007) for both months. When the centroid points were selected based on the significance of risk of DD, the correlations between MR and DD are not statistically significant for any month. Correlation between MR and DD based on the sets of P-value surfaces from 4 MR clusters are significant in gestational month 5, 6 and 7 with correlation 0.17 (P = 0.047), 0.16 (P = 0.060) and 0.17 (P = 0.044), respectively. Our finding suggests that locations of high risk for the more severe condition, MR, also identify a spatial area where less severe cases of DD might be present, however the reverse is not the case.

Item Type: Article
Uncontrolled Keywords: mental retardation, developmental delay, spatial clusters, South Carolina
Subjects: 600 Tecnologia - Scienze applicate > 610 Medicina e salute (Classificare qui la tecnologia dei servizi medici)
Depositing User: Emanuele Zinevrakis
Date Deposited: 30 Jun 2010 12:41
Last Modified: 30 Jun 2010 12:41

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