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Purpose: To quantify visual field (VF) variability as a function of threshold sensitivity and location, and to compare weighted pointwise linear regression (PLR) with unweighted PLR and pointwise exponential regression (PER) for data fit and prediction ability., Methods: Two datasets were used for this retrospective study. The first was used to characterize and estimate VF variability, and included a total of 4,747 eyes of 3,095 glaucoma patients with six or more VFs and 3 years or more of follow-up. After performing PER for each series, standard deviation of residuals was quantified for each decibel of sensitivity as a measure of variability. A separate dataset was used to test and compare unweighted PLR, weighted PLR, and PER for data fit and prediction, and included 261 eyes of 176 primary open-angle glaucoma patients with 10 or more VFs and 6 years or more of follow-up., Results: The degree of variability changed as a function of threshold sensitivity with a zenith and a nadir at 33 and 11 dB, respectively. Variability decreased with eccentricity and was higher in the central 10° ( P < 0.001). Differences among the methods for data fit were negligible. PER was the best model to predict future sensitivity values in the mid term and long term., Conclusions: VF variability increases with the severity of glaucoma damage and decreases with eccentricity. Weighted linear regression neither improves model fit nor prediction. PER exhibited the best prediction ability, which is likely related to the nonlinear nature of long-term glaucomatous perimetric decay., Translational Relevance: This study suggests that taking into account heteroscedasticity has no advantage in VF modeling., (Copyright 2019 The Authors.)

Purpose: This study assessed the effectiveness of the HIV/sexually transmitted infection/pregnancy prevention program, It's Your Game: Keep It Real (IYG)., Methods: IYG was implemented by classroom teachers in 24 urban middle schools from 2012 to 2015. Using a quasi-experimental design, each year we surveyed ninth-grade students in 10 high schools that were selected based on feeder patterns from project middle schools. We compared two groups of students (n = 4,562): (1) students whose middle school grade cohorts did not receive IYG ("No-IYG"), and (2) students whose middle school grade cohorts received IYG ("IYG"). Multilevel analyses examined differences between the two groups in the initiation of any type of sexual activity (oral, vaginal, or anal sex), presexual behaviors, and psychosocial mediators., Results: Students in the IYG group were less likely to report initiation of sexual activity by ninth grade compared to students in the No-IYG group (odds ratio .77; 95% confidence interval .66-.90). The IYG group was significantly less likely to have engaged in presexual behaviors, including having been on a date, had a boyfriend/girlfriend, and touched or been touched on private body parts. The IYG group had better outcomes on 11 of 19 psychosocial variables, including knowledge; beliefs about abstinence, sex, friends' beliefs, norms, and behaviors; reasons for not having sex; personal limits; exposure to risky situations; self-efficacy; and quality of dating relationships., Conclusions: The results suggest that IYG, when implemented on a large scale by trained classroom teachers in urban public schools, had positive impacts on students' behaviors, beliefs, and knowledge., (Copyright © 2018. Published by Elsevier Inc.)

Purpose: To develop a method to measure the rate of glaucomatous visual field (VF) deterioration and to identify fast progressors., Methods: Retrospective, longitudinal, observational study of 8486 eyes of 4610 glaucomatous patients with ≥6 VFs and ≥3 years of follow-up. A Glaucoma Rate Index (GRI) was calculated. VF locations were partitioned into exponential decay or exponential improvement models. A pointwise rate of change (PRC) was estimated with an exponential fit and expressed as the percent/year change of the age- and location-matched normal perimetric range, presented as a spatially conserved VF map. PRCs were summed and normalized with boundary rates set by simulated decaying and improving VF series on a scale of -100 to +100, respectively., Results: A total of 89,704 VF examinations with 425,039 test location series was used. Median follow-up and number of VFs/eye were 9.7 years and 9 VFs, respectively. Initial and final mean deviations (±SD) were -4.2 (±5.2) and -5.7 (±6.4) dB. The proportions of test locations designated as decayed, improved, and unchanged were 13%, 4%, and 83%, respectively. Mean PRCs for decay, improvement, and no change were -3.7 (±4.7)%/y, 2.5 (±2.6)%/y, and -0.5 (±2.1)%/y, respectively. The number of eyes with negative and positive GRIs was 5802 (68%) and 2390 eyes (28%), respectively. The proportion of eyes defined as fast progressors was 6.8%., Conclusions: GRI provides a robust measure of glaucomatous VF change, operates without discontinuity over the entire perimetric range, and can be used to identify fast progressors., Translational Relevance: This study describes a novel method that can help the clinician to determine VF progression.

Purpose: To test the hypothesis that vertical asymmetry in macular ganglion cell/inner plexiform layer (GCIPL) thickness can improve detection of early glaucoma., Methods: Sixty-nine normal eyes and 101 glaucoma eyes had macular imaging with spectral-domain optical coherence tomography (OCT; 200 × 200 cube). The resulting GCIPL thickness matrix was grouped into a 20 × 20 superpixel array and superior superpixels were compared to their inferior counterparts. A global asymmetry index (AI) was defined as the grand mean of the asymmetry ratios. To measure local asymmetry, the corresponding thickness measurements of three rows above and below the horizontal raphe were compared individually and in combinations. Global and local AIs were compared to the best-performing GCIPL thickness parameters with area under the receiver operating curves (AUC) and sensitivity/specificities., Results: Age or axial length did not influence AIs in normal subjects (P ≥ 0.08). Global and local AIs were significantly higher in the glaucoma group compared to normal eyes. Minimum (AUC = 0.962, 95% confidence interval [CI]: 0.936-0.989) and inferotemporal thickness (AUC = 0.944, 95% CI: 0.910-0.977; P = 0.122) performed best for detection of early glaucoma. The AUC for global AI was 0.851 (95% CI: 0.792-0.909) compared to 0.916 (95% CI: 0.874-0.958) for the best local AI. Combining minimum or inferotemporal GCIPL thickness and the best local AI led to higher partial AUCs (0.088 and 0.085, 90% specificity, P = 0.120 and 0.130, respectively) than GCIPL thickness measures., Conclusions: Macular vertical thickness asymmetry measures did not perform better than sectoral or minimum GCIPL thickness for detection of early glaucoma. Combining local asymmetry parameters with the best sectoral GCIPL thickness measures enhanced this task.

Purpose: To evaluate and compare the ability of pointwise linear, exponential, and logistic functions, and combinations of functions, to model the longitudinal behavior of visual field (VF) series and predict future VF loss in patients with glaucoma., Methods: Visual field series from 782 eyes (572 patients) with open-angle glaucoma had greater than 6 years of follow-up and 12 VFs performed. Threshold sensitivities from the first 5 years at each location were regressed with linear, exponential, and logistic functions to estimate model parameters. A multiple-model approach applied the model with the lowest root mean square error (RMSE) at each location as the preferred model for future predictions. Predictions for each model were compared at 1, 2, 3, and 5 years after the last VF used to determine model parameters., Results: There were no clinically important differences between any of the models tested for fit; however, the logistic function had the lowest average RMSE (P < 0.001). For predictions, the exponential model consistently had the lowest average prediction RMSE for all time intervals (P < 0.001); the multiple-model approach did not perform better than the exponential model (P < 0.001)., Conclusions: While the logistic model best fit glaucomatous VF behavior over a long time period, the exponential model provided the best average predictions. A multiple-model approach for VF predictions was associated with a greater prediction error than with the best-performing single-model approach. A model's goodness of fit is not indicative of its predictive ability for measurements of glaucomatous VFs., (Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.)

Purpose: This study was conducted to measure the rate of visual field (VF) decay in glaucoma, to separate faster and slower components of decay, and to predict the rate of VF decay., Methods: Patients who had primary glaucoma and 6 or more years of follow-up were included. Thresholds at each VF location were regressed with linear, quadratic, and exponential models. The best model was used to parse the VF into slower and faster rate components. Two independent cohorts (glaucoma [n = 87] and cataract [n = 38]) were used to determine the technique's ability to distinguish areas of glaucomatous VF changes from those caused by cataract. VF forecasts, derived from the first half of follow-up, were compared with actual VF thresholds at the end of follow-up., Results: The mean (±SD) years of follow-up and number of VFs for the main cohort (389 eyes of 309 patients) were 8.2 (±1.1) years and 15.7 (±3.0), respectively. The proportions of best fits were linear 2%, quadratic 1%, and exponential 97%. Proportions of eyes with exponential rates of decay ≥10% for the entire visual field (VF), faster components, and slower components were 20%, 56%, and 4%, respectively. The difference in decay rates between the faster and slower components was greater in the independent glaucoma cohort (19% ± 10%) than in the cataract cohort (5% ± 5%; P < 0.001). Test location forecasts significantly correlated with measured values (r(2) = 0.67; P < 0.001)., Conclusions: This method isolates faster and slower components of VF decay in glaucoma, can identify patients who are fast progressors, and can predict patterns of future VF loss with appropriate confidence intervals. (ClinicalTrials.gov number, NCT00000148.).

Objective: To measure possible racial/ethnic differences in a Florida disease management (DM) program on utilization of selected healthcare services for 4 chronic illnesses., Study Design: Pre-post comparison of utilization among 15,275 high-risk beneficiaries enrolled in DM in the Florida Medicaid program between October 2001 and October 2003., Methods: Two-part regression analyses of the effect of DM on annualized inpatient days, emergency department (ED) visits, and outpatient visits, controlling for relevant covariates. Annualized rates were used to adjust for differences in length of program enrollment., Results: Disease management patients in the postperiod had significantly lower annual rates of inpatient days, ED visits, and outpatient visits across most racial/ethnic groups. Disease management reduced utilization by a similar absolute amount in each racial/ethnic group. However, baseline disparities in utilization of inpatient days were not reduced by the DM program., Conclusions: Disease management has a similar effect across different racial/ethnic groups but may not ameliorate important baseline disparities. Evaluations of DM programs should account for baseline disparities in utilization and examine whether those disparities can be reduced through DM.

Introduction: The association between exposure to extremely low-frequency electric and magnetic fields (ELF) and childhood leukemia has led to the classification of magnetic fields by the International Agency for Research on Cancer as a "possible human carcinogen." This association is regarded as the critical effect in risk assessment. Creating effective policy in light of widespread exposure and the undisputed value of safe, reliable, and economic electricity to society is difficult and requires estimates of the potential public health impact and associated uncertainties., Objectives: Although a causal relationship between magnetic fields and childhood leukemia has not been established, we present estimates of the possible pubic health impact using attributable fractions to provide a potentially useful input into policy analysis under different scenarios., Methods: Using ELF exposure distributions from various countries and dose-response functions from two pooled analyses, we calculate country-specific and worldwide estimates of attributable fractions (AFs) and attributable cases., Results: Even given a wide range of assumptions, we find that the AF remains < 10%, with point estimates ranging from < 1% to about 4%. For small countries with low exposure, the number of attributable cases is less than one extra case per year. Worldwide the range is from 100 to 2,400 cases possibly attributable to ELF exposure., Conclusion: The fraction of childhood leukemia cases possibly attributable to ELF exposure across the globe appears to be small. There remain, however, a number of uncertainties in these AF estimates, particularly in the exposure distributions.