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BackgroundIndividual behaviours are associated with prostate cancer (PC) progression. Behavioural scores, comprised of multiple risk factors, allow assessment of the combined impact of multiple behaviours.MethodsWe examined the association between six a priori scores and risk of PC progression and mortality among 2156 men with PC in the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) cohort: two scores developed based on the PC survivorship literature ('2021 Score [+ Diet]'); a score developed based on pre-diagnostic PC literature ('2015 Score'); and three scores based on US recommendations for cancer prevention ('WCRF/AICR Score') and survival ('ACS Score [+ Alcohol]'). Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for progression and PC mortality via parametric survival models (interval censoring) and Cox models, respectively.ResultsOver a median (IQR) of 6.4 (1.3, 13.7) years, we observed 192 progression and 73 PC mortality events. Higher (i.e., healthier) 2021 Score + Diet and WCRF/AICR Scores were inversely associated with risk of PC progression (2021 + Diet: HRcontinuous = 0.76, 95% CI: 0.63-0.90.Wcrf/aicrHRcontinuous = 0.83, 95% CI: 0.67-1.02) and mortality (2021 + Diet: HRcontinuous = 0.65, 95% CI: 0.45-0.93.Wcrf/aicrHRcontinuous = 0.71; 95% CI: 0.57-0.89). The ACS Score + Alcohol was only associated with progression (HRcontinuous = 0.89, 95% CI: 0.81-0.98) while the 2021 Score was only associated with PC mortality (HRcontinuous = 0.62, 95% CI: 0.45-0.85). The 2015 was not associated with PC progression or mortality.ConclusionFindings strengthen the evidence that behavioural modifications following a prostate cancer diagnosis may improve clinical outcomes.

After introducing guidelines for breast cancer screening in 2003, Mexico began to prioritize the implementation of mammography screening nationally. Since then, there have been no studies assessing changes in mammography in Mexico using the two-year prevalence interval that corresponds to national guidelines for screening frequency. The present study analyzes the Mexican Health and Aging Study (MHAS), a national population-based panel study of adults aged 50 and older, to evaluate changes in 2-year mammography prevalence among women aged 50 to 69 across five survey waves from 2001 to 2018 (n = 11,773). We calculated unadjusted and adjusted mammography prevalence by survey year and health insurance type. Overall prevalence increased substantially from 2003 to 2012 and leveled off in the period from 2012 to 2018 (2001: 20.2 % [95 % CI 18.3, 22.1]; 2003: 22.7 % [20.4, 25.0]; 2012: 56.5 % [53.2, 59.7]; 2015: 62.0 % [58.8, 65.2]; 2018: 59.4 % [56.7,62.1]; unadjusted prevalence). Prevalence was higher among respondents with social security insurance, who are more likely to work in the formal economy, than among respondents without social security, who are more likely to work in the informal economy or be unemployed. The overall prevalence estimates observed were higher than previously published estimates of mammography prevalence in Mexico. More research is needed to confirm findings regarding two-year mammography prevalence in Mexico and to better understand the causes of observed disparities.

BackgroundRecent endeavors emphasize the importance of understanding early barriers to liver transplantation (LT) by consistently collecting data on patient demographics, socioeconomic factors, and geographic social deprivation indices.MethodsIn this retrospective single-center cohort study of 1657 adults referred for LT evaluation, we assessed the association between community-level vulnerability and individual socioeconomic status measures on the rate of waitlisting and transplantation. Patients' addresses were linked to Social Vulnerability Index (SVI) at the census tract-level to characterize community-level vulnerability. Descriptive statistics were used to describe patient characteristics. Multivariable cause-specific HRs were used to assess the association between community-level vulnerability, individual measures of the socioeconomic status, and LT evaluation outcomes (waitlist and transplantation).ResultsAmong the 1657 patients referred for LT during the study period, 54% were waitlisted and 26% underwent LT. A 0.1 increase in overall SVI correlated with an 8% lower rate of waitlisting (HR 0.92, 95% CI 0.87-0.96, p < 0.001), with socioeconomic status, household characteristics, housing type and transportation, and racial and ethnic minority status domains contributing significantly to this association. Patients residing in more vulnerable communities experienced a 6% lower rate of transplantation (HR 0.94, 95% CI 0.91- 0.98, p = 0.007), with socioeconomic status and household characteristic domain of SVI significantly contributing to this association. At the individual level, both government insurance and employment status were associated with lower rates of waitlisting and transplantation. There was no association with mortality prior to waitlisting or mortality while on the waitlist.ConclusionOur findings indicate that both individual and community measures of the socioeconomic status (overall SVI) are associated with LT evaluation outcomes. Furthermore, we identified individual measures of neighborhood deprivation associated with both waitlisting and transplantation.

BackgroundHispanic subjects with cystic fibrosis (CF) have increased morbidity and mortality than non-Hispanic white subjects. The ethnic disparity in mortality varies by region. Factors influencing pulmonary function vary by both ethnicity and region.ObjectiveTo determine if the ethnic difference in pulmonary function varies by region.MethodsThis retrospective cohort study compared differences in longitudinal pulmonary function (percent-predicted forced vital capacity [FVC], forced expiratory volume in 1 second [FEV1 ], forced expiratory flow at 25% to 75% [FEF25-75 ], FEV1 /FVC, and FEV1 decline) between Hispanic and non-Hispanic white subjects with CF by Census region of the United States (West, South, Midwest, and Northeast). Subjects were of ages 6 to 25 years and in the CF Foundation Patient Registry from 2008 to 2013. We used linear mixed effects models with subject-specific slopes and intercepts, adjusting for 14 demographic and clinical variables.ResultsOf 14 932 subjects, 1433 (9.6%) were Hispanic and 13 499 (90.4%) were non-Hispanic white. Hispanic subjects' FEV1 was 9.0% (8.3%-9.8%) lower than non-Hispanic white subjects in the West, while Hispanic subjects' FEV1 was only 4.0% (3.0%-5.0%) lower in the Midwest, 4.4% (3.1%-5.7%) lower in the Northeast, and 4.4% (3.2%-5.5%) lower in the South. Similarly, FVC and FEF25-75 were lower among Hispanic subjects compared to non-Hispanic white subjects in all US regions, with the biggest differences in the West. Only in the West was FEV1 /FVC significantly lower in Hispanic subjects (-0.019; -0.022 to -0.015). FEV1 decline was not significantly different between ethnicities in any region.ConclusionsIn CF, Hispanic subjects have lower pulmonary function than non-Hispanic white subjects in all geographic regions with the largest difference in occurring in the West.

BackgroundHispanic patients with cystic fibrosis (CF) have decreased life expectancy compared to non-Hispanic white patients. Pulmonary function is a main predictor of life expectancy in CF. Ethnic differences in pulmonary function in CF have been understudied. The objective was to compare longitudinal pulmonary function between Hispanic and non-Hispanic white patients with CF.MethodsThis cohort study of 15 018 6-25 years old patients in the CF Foundation Patient Registry from 2008 to 2013 compared FEV1 percent predicted and longitudinal change in FEV1 percent predicted in Hispanic to non-Hispanic white patients. We used linear mixed effects models with patient-specific slopes and intercepts, adjusting for 14 demographic and clinical variables. We did sub-analyses by CFTR class, F508del copies, and PERT use.ResultsHispanic patients had lower FEV1 percent predicted (79.9%) compared with non-Hispanic white patients (85.6%); (-5.8%, 95%CI -6.7% to -4.8%, P  0.05) or between F508del copies (None: -7.6%, Heterozygotes: -5.6%, Homozygotes: -5.3%, P > 0.05).ConclusionsDisparities in pulmonary function exist in Hispanic patients with CF early in life and then persist without improving or worsening over time. It is valuable to investigate the factors contributing to pulmonary function in Hispanic patients with CF.

BackgroundWith the onset of prevention trials for individuals at high risk for Alzheimer disease, there is increasing need for accurate risk prediction to inform study design and enrollment, but available risk estimates are limited. We developed risk estimates for the incidence of mild cognitive impairment (MCI) or dementia among cognitively unimpaired individuals by APOE-e4 dose for the genetic disclosure process of the Alzheimer's Prevention Initiative Generation Study, a prevention trial in cognitively unimpaired APOE-e4/e4 homozygote individuals.Methods and findingsWe included cognitively unimpaired individuals aged 60-75 y, consistent with Generation Study eligibility criteria, from the National Alzheimer's Coordinating Center (NACC) (n = 5,073, 158 APOE-e4/e4), the Rotterdam Study (n = 6,399, 156 APOE-e4/e4), the Framingham Heart Study (n = 4,078, 67 APOE-e4/e4), and the Sacramento Area Latino Study on Aging (SALSA) (n = 1,294, 11 APOE-e4/e4). We computed stratified cumulative incidence curves by age (60-64, 65-69, 70-75 y) and APOE-e4 dose, adjusting for the competing risk of mortality, and determined risk of MCI and/or dementia by genotype and baseline age. We also used subdistribution hazard regression to model relative hazard based on age, APOE genotype, sex, education, family history of dementia, vascular risk, subjective memory concerns, and baseline cognitive performance. The four cohorts varied considerably in age, education, ethnicity/race, and APOE-e4 allele frequency. Overall, cumulative incidence was uniformly higher in NACC than in the population-based cohorts. Among APOE-e4/e4 individuals, 5-y cumulative incidence was as follows: in the 60-64-y age stratum, it ranged from 0% to 5.88% in the three population-based cohorts versus 23.06% in NACC; in the 65-69-y age stratum, from 9.42% to 10.39% versus 34.62%; and in the 70-75-y age stratum, from 18.64% to 33.33% versus 38.34%. Five-year incidence of dementia was negligible except for APOE-e4/e4 individuals and those over 70 y. Lifetime incidence (to age 80-85 y) of MCI or dementia for the APOE-e4/e4 individuals in the long-term Framingham and Rotterdam cohorts was 34.69%-38.45% at age 60-64 y, 30.76%-40.26% at 65-69 y, and 33.3%-35.17% at 70-75 y. Confidence limits for these estimates are often wide, particularly for APOE-e4/e4 individuals and for the dementia outcome at 5 y. In regression models, APOE-e4 dose and age both consistently increased risk, as did lower education, subjective memory concerns, poorer baseline cognitive performance, and family history of dementia. We discuss several limitations of the study, including the small numbers of APOE-e4/e4 individuals, missing data and differential dropout, limited ethnic and racial diversity, and differences in definitions of exposure and outcome variables.ConclusionsEstimates of the absolute risk of MCI or dementia, particularly over short time intervals, are sensitive to sampling and a variety of methodological factors. Nonetheless, such estimates were fairly consistent across the population-based cohorts, and lower than those from a convenience cohort and those estimated in prior studies-with implications for informed consent and design for clinical trials targeting high-risk individuals.

The availability of data in longitudinal studies is often driven by features of the characteristics being studied. For example, clinical databases are increasingly being used for research to address longitudinal questions. Because visit times in such data are often driven by patient characteristics that may be related to the outcome being studied, the danger is that this will result in biased estimation compared to designed, prospective studies. We study longitudinal data that follow a generalized linear mixed model and use a log link to relate an informative visit process to random effects in the mixed model. This device allows us to elucidate which parameters are biased under the informative visit process and to what degree. We show that the informative visit process can badly bias estimators of parameters of covariates associated with the random effects, while allowing consistent estimation of other parameters.

ObjectiveTo examine the influence of neighbourhood socioeconomic position (NSEP) on development of diabetes over time.DesignA longitudinal cohort study.SettingThe data reported were from the Sacramento Area Latino Study on Aging, a longitudinal study of the health of 1789 older Latinos.ParticipantsCommunity-dwelling older Mexican Americans residing in the Sacramento Metropolitan Statistical Area.Main outcomeMultistate Markov regression were used to model transitions through four possible states over time: 1=normal; 2=pre-diabetic; 3=diabetic; and 4=death without diabetes.ResultsAt baseline, nearly 50% were non-diabetic, 17.5% were pre-diabetic and nearly 33% were diabetic. At the end of follow-up, there were a total of 824 people with type 2 diabetes. In a fully adjusted MSM regression model, among non-diabetics, higher NSEP was not associated with a transition to pre-diabetes. Among non-diabetics, higher NSEP was associated with an increased risk of diabetes (HR=1.66, 95% CI 1.14 to 2.42) and decreased risk of death without diabetes (HR: 0.56, 95% CI 0.33 to 0.96). Among pre-diabetics, higher NSEP was significantly associated with a transition to non-diabetic status (HR: 1.22, 95% CI 0.99 to 1.50). Adjusting for BMI, age, education, physical activity, smoking, alcohol consumption, medical insurance and nativity did not affect this relationship.ConclusionsOur findings show that high NSEP poses higher risk of progression from normal to diabetes compared with a lower risk of death without diabetes. This work presents a possibility that these associations are modified by nativity or culture.

BackgroundComorbidity (COM) is an important issue in aging. Cardiovascular disease (CVD) and osteoarthritis separately and together may modify the trajectories of functional decline. This analysis examines whether specific and unrelated COMs influence functional change differently and vary by gender.MethodsA cohort study of 1,789 (aged 60 years and older) Mexican Americans was followed annually for up to 10 years. We created four groups of COM (CVD alone, lower body osteoarthritis alone [OA], neither, or both). We employed mixed effects Poisson models with Instrumental Activities of Daily Living (IADL) as the outcome. We tested whether the association between COM and decline in functional status differed by gender.ResultsIADL impairments in those with CVD, OA, or both were significantly higher at baseline and increased more rapidly over time compared to those with neither condition. Compared to women with no COM, the number of IADL impairments in women with CVD alone were 1.36 times greater, with OA were 1.35 times greater, and both conditions were 1.26 times greater. Compared to men with no COM, IADL impairments in men with CVD alone were 1.15 times greater, OA alone were 1.12 times greater, and both were 1.26 times greater.ConclusionsOver time, the influence of COM on functional decline differs by specific combinations of COM and by gender. Aggregate COM scales obscure the biological and temporal heterogeneity in the effects of COM. Time-dependent-specific COMs better assess the development of impairment. Women experience a higher burden of functional impairment due to COM than men.

BackgroundBlack and Hispanic older Americans are less likely than white older Americans to possess advance directives. Understanding the reasons for this racial and ethnic difference is necessary to identify targets for future interventions to improve advance care planning in these populations.MethodsThe aim of the study was to evaluate whether racial and ethnic differences in advance directive possession are explained by other demographic factors, religious characteristics, and personal health values. A general population survey was conducted in a nationally representative sample using a web-enabled survey panel of American adults aged 50 and older (n = 2154).ResultsIn a sample of older Americans, white participants are significantly more likely to possess advance directives (44.0%) than black older Americans (24.0%, p

PurposeAlthough fear of recurrence (FCR) is common among cancer survivors, it remains unclear what factors predict initial levels (e.g., prior to surgery) or changes in FCR in the post-treatment period. Among women treated for breast cancer, this study evaluated the effects of demographic, clinical, symptom, and psychosocial adjustment characteristics on the initial (preoperative) levels of FCR and trajectories of FCR over 6 months following surgery.MethodsPrior to and for 6 months following breast cancer surgery, 396 women were assessed for demographic and clinical (disease and treatment) characteristics, symptoms, psychological adjustment characteristics, and quality of life (QOL). FCR was assessed using a four-item subscale from the QOL instrument. Hierarchical linear modeling was used to examine changes in FCR scores and to identify predictors of inter-individual differences in preoperative FCR levels and trajectories over 6 months.ResultsFrom before surgery to 6 months post-operatively, women with breast cancer showed a high degree of inter-individual variability in FCR. Preoperatively, women who lived with someone, experienced greater changes in spiritual life, had higher state anxiety, had more difficulty coping, or experienced more distress due to diagnosis or distress to family members reported higher FCR scores. Patients who reported better overall physical health and higher FCR scores at enrollment demonstrated a steeper decrease in FCR scores over time.ConclusionsThese findings highlight inter-individual heterogeneity in initial levels and changes in FCR over time among women undergoing breast cancer surgery. Further work is needed to identify and provide interventions for women experiencing FCR during and after breast cancer treatment.

Investigators often gather longitudinal data to assess changes in responses over time within subjects and to relate these changes to within-subject changes in predictors. Missing data are common in such studies and predictors can be correlated with subject-specific effects. Maximum likelihood methods for generalized linear mixed models provide consistent estimates when the data are `missing at random' (MAR) but can produce inconsistent estimates in settings where the random effects are correlated with one of the predictors. On the other hand, conditional maximum likelihood methods (and closely related maximum likelihood methods that partition covariates into between- and within-cluster components) provide consistent estimation when random effects are correlated with predictors but can produce inconsistent covariate effect estimates when data are MAR. Using theory, simulation studies, and fits to example data this paper shows that decomposition methods using complete covariate information produce consistent estimates. In some practical cases these methods, that ostensibly require complete covariate information, actually only involve the observed covariates. These results offer an easy-to-use approach to simultaneously protect against bias from both cluster-level confounding and MAR missingness in assessments of change.

UnlabelledPersistent pain following breast cancer surgery is well documented. However, it is not well characterized in terms of the anatomic site affected (ie, breast, arm). In 2 separate growth mixture modeling analyses, we identified subgroups of women (N = 398) with distinct breast pain and arm pain trajectories. The fact that these latent classes differed by anatomic site, types of tissue affected, and neural innervation patterns suggests the need for separate evaluations of these distinct persistent pain conditions. The purposes of this companion study were to identify demographic and clinical characteristics that differed between the 2 arm pain classes and determine if differences existed over time in sensitivity in the upper inner arm and axillary lymph node dissection sites, pain qualities, pain interference, and hand and arm function, as well as to compare findings with persistent breast pain. Higher occurrence rates for depression and lymphedema were found in the moderate arm pain class. Regardless of pain group membership, sensory loss was observed in the upper inner arm and axillary lymph node dissection site. Arm pain was described similarly to neuropathic pain and interfered with daily functioning. Persistent arm pain was associated with sustained impairments in shoulder mobility.PerspectiveFor persistent breast and arm pain, changes in sensation following breast cancer surgery were notable. Persistent arm pain was associated with sustained interference with daily functioning and upper body mobility impairments. Long-term management of persistent pain following breast cancer surgery is warranted to improve the quality of survivorship for these women.

Investigators commonly gather longitudinal data to assess changes in responses over time and to relate these changes to within-subject changes in predictors. With rare or expensive outcomes such as uncommon diseases and costly radiologic measurements, outcome-dependent, and more generally outcome-related, sampling plans can improve estimation efficiency and reduce cost. Longitudinal follow up of subjects gathered in an initial outcome-related sample can then be used to study the trajectories of responses over time and to assess the association of changes in predictors within subjects with change in response. In this article, we develop two likelihood-based approaches for fitting generalized linear mixed models (GLMMs) to longitudinal data from a wide variety of outcome-related sampling designs. The first is an extension of the semi-parametric maximum likelihood approach developed in Neuhaus, Scott and Wild (2002, Biometrika 89, 23-37) and Neuhaus, Scott and Wild (2006, Biometrics 62, 488-494) and applies quite generally. The second approach is an adaptation of standard conditional likelihood methods and is limited to random intercept models with a canonical link. Data from a study of attention deficit hyperactivity disorder in children motivates the work and illustrates the findings.

ObjectiveTo determine whether oral quinacrine increases survival in sporadic Creutzfeldt-Jakob disease (sCJD).MethodsThis NIH/National Institute on Aging-funded, double-blinded, placebo-controlled, stratified randomization treatment trial was conducted at the University of California, San Francisco from February 2005 through May 2009 (ClinicalTrials.gov, NCT00183092). Subjects were randomized (50:50) to quinacrine (300 mg daily) or placebo with inpatient evaluations at baseline, and planned for months 2, 6, and 12. Subjects returning for their month-2 visit were offered open-label quinacrine. The primary outcome was survival from randomization to month 2.ResultsOf 425 patients referred, 69 subjects enrolled, 54 subjects were randomized to active drug or placebo, and 51 subjects with sCJD were included in survival analyses. Survival for the randomized portion of the trial (first 2 months) showed no significant difference between the 2 groups (log-rank statistic, p = 0.43; Cox proportional relative hazard = 1.43, quinacrine compared with placebo, 95% confidence interval = 0.58, 3.53). The quinacrine-treated group, however, declined less on 2 of 3 functional scales, the modified Rankin and Clinical Dementia Rating, than the placebo group during the first 2 months.ConclusionThis interventional study provides Class I evidence that oral quinacrine at 300 mg per day does not improve 2-month survival of patients with sCJD, compared with placebo. Importantly, this study shows that double-blinded, placebo-controlled, randomized treatment trials are possible in prion disease. Furthermore, the quantitative data collected on the course of sCJD will be useful for future trials.Classification of evidenceThis study provides Class I evidence that quinacrine does not improve survival for people with sCJD when given orally at a dose of 300 mg per day for 2 months.

BackgroundThe purpose of this study was to examine the associations of cardiovascular disease (CVD) risk with cognitive decline and incidence of dementia and cognitive impairment but not dementia (CIND) and the role of education as a modifier of these effects.Methods and resultsOne thousand one hundred sixteen Mexican American elderly were followed annually in the Sacramento Area Latino Study on Aging. Our sex-specific 10-year CVD risk score included baseline age, systolic blood pressure, total cholesterol, high-density lipoprotein, smoking, body mass index, and diabetes. From adjusted linear mixed models, errors on the Modified Mini-Mental State Exam (3MSE) were annually 0.41% lower for women at the 25th percentile of CVD risk, 0.11% higher at the 50th percentile, and 0.83% higher at the 75th percentile (P value of CVDrisk×time

BackgroundThe purpose of this study was to examine the associations of cardiovascular disease (CVD) risk with cognitive decline and incidence of dementia and cognitive impairment but not dementia (CIND) and the role of education as a modifier of these effects.Methods and resultsOne thousand one hundred sixteen Mexican American elderly were followed annually in the Sacramento Area Latino Study on Aging. Our sex-specific 10-year CVD risk score included baseline age, systolic blood pressure, total cholesterol, high-density lipoprotein, smoking, body mass index, and diabetes. From adjusted linear mixed models, errors on the Modified Mini-Mental State Exam (3MSE) were annually 0.41% lower for women at the 25th percentile of CVD risk, 0.11% higher at the 50th percentile, and 0.83% higher at the 75th percentile (P value of CVDrisk×time

BackgroundThe peak incidence of Ewing sarcoma (EWS) is in adolescence, with little known about patients who are ≥40 years at diagnosis. We describe the clinical characteristics and survival of this rare group.MethodsThis retrospective cohort study utilized the Surveillance Epidemiology and End Results database. 2780 patients were identified; including 383 patients diagnosed ≥40 years. Patient characteristics between age groups were compared using chi-squared tests. Survival from diagnosis to death was estimated via Kaplan-Meier methods, compared with log-rank tests, and modeled using multivariable Cox methods. A competing risks analysis was performed to evaluate death due to cancer.ResultsPatients ≥40 years of age were more likely to have extra-skeletal tumors (66.1% vs. 31.7%; p < 0.001), axial tumors (64.0% vs. 57.2%; p = 0.01), and metastatic disease at diagnosis (35.5% vs. 30.0%; p = 0.04) compared to younger patients. Five-year survival for those age ≥40 and age

The neural underpinnings of sensory processing differences in autism remain poorly understood. This prospective magnetoencephalography (MEG) study investigates whether children with autism show atypical cortical activity in the primary somatosensory cortex (S1) in comparison with matched controls. Tactile stimuli were clearly detectable, and painless taps were applied to the distal phalanx of the second (D2) and third (D3) fingers of the right and left hands. Three tactile paradigms were administered: an oddball paradigm (standard taps to D3 at an interstimulus interval (ISI) of 0.33 and deviant taps to D2 with ISI ranging from 1.32 s to 1.64 s); a slow-rate paradigm (D2) with an ISI matching the deviant taps in the oddball paradigm; and a fast-rate paradigm (D2) with an ISI matching the standard taps in the oddball. Study subjects were boys (age 7-11 years) with and without autism disorder. Sensory behavior was quantified using the Sensory Profile questionnaire. Boys with autism exhibited smaller amplitude left hemisphere S1 response to slow and deviant stimuli during the right-hand paradigms. In post-hoc analysis, tactile behavior directly correlated with the amplitude of cortical response. Consequently, the children were re-categorized by degree of parent-report tactile sensitivity. This regrouping created a more robust distinction between the groups with amplitude diminution in the left and right hemispheres and latency prolongation in the right hemisphere in the deviant and slow-rate paradigms for the affected children. This study suggests that children with autism have early differences in somatosensory processing, which likely influence later stages of cortical activity from integration to motor response.

Statistical models that generate predicted random effects are widely used to evaluate the performance of and rank patients, physicians, hospitals and health plans from longitudinal and clustered data. Predicted random effects have been proven to outperform treating clusters as fixed effects (essentially a categorical predictor variable) and using standard regression models, on average. These predicted random effects are often used to identify extreme or outlying values, such as poorly performing hospitals or patients with rapid declines in their health. When interest focuses on the extremes rather than performance on average, there has been no systematic investigation of best approaches. We develop novel methods for prediction of extreme values, evaluate their performance, and illustrate their application using data from the Osteoarthritis Initiative to predict walking speed in older adults. The new methods substantially outperform standard random and fixed-effects approaches for extreme values. [ABSTRACT FROM AUTHOR]

Objectives. We sought to determine the effectiveness of a systems-based intervention designed to increase Chlamydia trachomatis (CT) screening among adolescent boys. Methods. An intervention aimed at increasing CT screening among adolescent girls was extended to adolescent boys (14-18 years). Ten pediatric clinics in a health maintenance organization with an ethnically diverse population were randomized. Experimental clinics participated in a clinical practice improvement intervention; control clinics received traditional information on screening. Results. The intervention significantly increased CT screening at the experimental sites from 0% (baseline) to 60% (18-month posttest); control sites evidenced a change only from 0% to 5%. The overall prevalence of CT was 4%. Conclusions. Although routine CT screening is currently recommended only for young sexually active women, the present results show that screening interventions can be successful in the case of adolescent boys, among whom CT is a moderate problem. (Am J Public Health. 2005;95:1806-1810. doi:10.2105/AJPH.2003.037507)

A clinical practice improvement method is described that increased the number of sexually active teenagers who were tested for chlamydia infection at five pediatric clinics. It involves determining the optimal practice, assembling a team that will promote the new practice, identifying and eliminating any barriers to the practice, and evaluating the outcome of the practice. Chlamydia is a common sexually transmitted disease but many teenagers do not know they have it.

Paramedics can use benzodiazepines to treat status epilepticus and lorazepam is more effective than diazepam. Status epilepticus is a prolonged or repetitive seizure that must be treated quickly.