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Objective

To derive and validate a new ecological measure of the social determinants of health (SDoH), calculable at the zip code or county level.

Data Sources and Study Setting

The most recent releases of secondary, publicly available data were collected from national U.S. health agencies as well as state and city public health departments.

Study Design

The Social Vulnerability Metric (SVM) was constructed from U.S. zip-code level measures (2018) from survey data using multidimensional Item Response Theory and validated using outcomes including all-cause mortality (2016), COVID-19 vaccination (2021), and emergency department visits for asthma (2018). The SVM was also compared with the existing Centers for Disease Control and Prevention's Social Vulnerability Index (SVI) to determine convergent validity and differential predictive validity.

Data Collection/Extraction Methods

The data were collected directly from published files available to the public online from national U.S. health agencies as well as state and city public health departments.

Principal Findings

The correlation between SVM scores and national age-adjusted county all-cause mortality was r = 0.68. This correlation demonstrated the SVM's robust validity and outperformed the SVI with an almost four-fold increase in explained variance (46% vs. 12%). The SVM was also highly correlated (r ≥ 0.60) to zip-code level health outcomes for the state of California and city of Chicago.

Conclusions

The SVM offers a measurement tool improving upon the performance of existing SDoH composite measures and has broad applicability to public health that may help in directing future policies and interventions. The SVM provides a single measure of SDoH that better quantifies associations with health outcomes.  相似文献   
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Ultrasound (US) and laboratory testing are initial diagnostic tests for acute appendicitis. A diagnostic dilemma develops when the appendix is not visualized on US. Objective: To determine if specific US findings and/or laboratory results predict acute appendicitis when the appendix is not visualized. Methods: A prospective study was conducted on children (birth-18?yrs) presenting to the pediatric emergency department with suspected acute appendicitis who underwent right lower quadrant US.Children with previous appendectomy, US at another facility, or eloped were excluded. US findings analyzed: inflammatory changes, right lower quadrant and lower abdominal fluid, tenderness during US exam and lymph nodes. Diagnoses were confirmed via surgical pathology. Results 1252 subjects were enrolled, 60.8% (762) had appendix visualized and 39.1% (490) did not. In children where the appendix was not seen, 6.7% [33] were diagnosed with appendicitis. Among patients with a non-visualized appendix, the likelihood of appendicitis was significantly greater if: inflammatory changes in the RLQ (OR 18.0, 95% CI 4.5–72.1), CRP >0.5?mg/dL (OR 2.64, 95% CI 1.0–6.8), or WBC?>?10 (OR 4.36, 95% CI 1.66–11.58). Duration of abdominal pain >3?days was significantly less likely associated with appendicitis in this model (OR 0.34, 95% CI 0.003–0.395). Combined, the absence inflammatory changes, CRP?<?0.5?mg/dL, WBC?<?10, and pain, ≤3?days had a NPV of 94.0%. Conclusion When the appendix is not visualized on US, predictors for appendicitis include the presence of inflammatory changes in the RLQ, an elevated WBC/CRP and abdominal pain <3?days.  相似文献   
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Rotavirus vaccine has reduced disease prevalence in many countries. Consequently, we aimed to assess the reliability of a rotavirus immunoassay in the community population of Auckland and Northland, New Zealand. Between 22 October 2015 and 31 December 2016, 2873 fecal samples were tested by enzyme immunoassay (EIA, Rotascreen II, Microgen, UK) from 2748 patients (median age 8?years, range 0–101?years). Eighty-nine (3.1%) samples were reactive; 86 samples were tested by a second method. Rotavirus was confirmed in 49/86 (57%). Positive rotavirus EIAs were more likely to be confirmed in samples from cases ≥1?year of age (positive predictive value [PPV] 61%, 95% confidence interval [CI] 50–72%, P?=?0.049) and in spring/summer (PPV 67%, 95% CI 55–78%, P?=?0.003). Reactive rotavirus tests required confirmatory testing regardless of demographic, vaccine, or seasonal factors; a review of rotavirus testing algorithms may be necessary in other vaccinated community populations.  相似文献   
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Background: Mechanisms underlying associations between early drinking and problems are largely unknown. Objectives: We investigated (a) associations between early age of first intoxication (≤15?years) and past year drinking in different contexts and (b) whether early age of first intoxication is differentially associated with problems in these contexts. Methods: We used survey data collected in 2013–2014 from 405 past-year adolescent drinkers in 24 midsized California cities. Data included demographics; drinking behaviors; age of first intoxication; frequency of being at and drinking at restaurants, bars/nightclubs, outdoor places, and home; and problems. We used multilevel logistic and negative binomial models to account for the clustering of adolescents within cities. Probabilities were corrected to maintain family-wise error rates. Results: Early age of first intoxication was associated with a 120% increase in the odds of drinking at outdoor settings (OR = 2.20, pc < .05). Early age of first intoxication was associated with increased numbers of problems related to drinking in restaurants (IRR = 5.72, pc < .001), outdoor settings (IRR = 3.40, pc < .001), and homes (IRR = 2.84, pc < .001). Later intoxication (≥16?years) was not significantly associated with increased drinking or problems in any of these contexts. Conclusions: Results suggest that underage drinkers who report early intoxication are more likely to drink at outdoor settings, but not other contexts. However, they may differentially experience drinking problems across contexts. To target youths who have experienced intoxication at an early age and to reduce problems, prevention interventions should focus on outdoor settings.  相似文献   
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