RAND Corporation

About: RAND Corporation is a nonprofit organization based out in Santa Monica, California, United States. It is known for research contribution in the topics: Health care & Population. The organization has 9602 authors who have published 18570 publications receiving 744658 citations.

Combining Propensity Score Matching and Group-Based Trajectory Analysis in an Observational Study.

Abstract: In a nonrandomized or observational study, propensity scores may be used to balance observed covariates and trajectory groups may be used to control baseline or pretreatment measures of outcome. The trajectory groups also aid in characterizing classes of subjects for whom no good matches are available and to define substantively interesting groups between which treatment effects may vary. These and related methods are illustrated using data from a Montreal-based study. The effects on subsequent violence of gang joining at age 14 are studied while controlling for measured characteristics of boys prior to age 14. The boys are divided into trajectory groups based on violence from ages 11 to 13. Within trajectory group, joiners are optimally matched to a variable number of controls using propensity scores, Mahalanobis distances, and a combinatorial optimization algorithm. Use of variable ratio matching results in greater efficiency than pair matching and also greater bias reduction than matching at a fixed ratio. The possible impact of failing to adjust for an important but unmeasured covariate is examined using sensitivity analysis.

High Prevalence of Abscesses and Cellulitis Among Community-Recruited Injection Drug Users in San Francisco

Abstract: The prevalence of and risk factors for abscesses and cellulitis were investigated among a community sample of injection drug users (IDUs). Participants were interviewed, and those with symptoms were examined. Of 169 IDUs, 54 (32%) had abscesses ( ), cellulitis ( n= 35 n= ), or both ( ); 27% had lanced their own abscesses; and 16% had self-treated with 5 n= 14 antibiotics they purchased on the street. IDUs who skin-popped (injected subcutaneously or intramuscularly) were more likely to have an abscess or cellulitis than those who had injected only intravenously (odds ratio, 4.9; 95% confidence interval, 2.2‐11). The likelihood of abscesses and cellulitis increased with frequency of skin-popping and decreased with increasing duration of injection drug use. Abscesses are extremely prevalent among IDUs in San Francisco. Skin-popping is a major risk factor, and self-treatment is common. Abscesses and cellulitis are a common problem among injection drug users (IDUs). Few previous studies have examined the prevalence of and risk factors for abscesses among IDUs. In this cross-sectional survey of street-recruited IDUs, we estimated the prevalence of abscesses and cellulitis among IDUs by examining all participants who reported symptoms of local infection. We also examined the risk factors for these infections and estimated the prevalence of related behaviors.

Nudging Guideline-Concordant Antibiotic Prescribing: A Randomized Clinical Trial

Abstract: Importance “Nudges” that influence decision making through subtle cognitive mechanisms have been shown to be highly effective in a wide range of applications, but there have been few experiments to improve clinical practice. Objective To investigate the use of a behavioral “nudge” based on the principle of public commitment in encouraging the judicious use of antibiotics for acute respiratory infections (ARIs). Design, Setting, and Participants Randomized clinical trial in 5 outpatient primary care clinics. A total of 954 adults had ARI visits during the study timeframe: 449 patients were treated by clinicians randomized to the posted commitment letter (335 in the baseline period, 114 in the intervention period); 505 patients were treated by clinicians randomized to standard practice control (384 baseline, 121 intervention). Interventions The intervention consisted of displaying poster-sized commitment letters in examination rooms for 12 weeks. These letters, featuring clinician photographs and signatures, stated their commitment to avoid inappropriate antibiotic prescribing for ARIs. Main Outcomes and Measures Antibiotic prescribing rates for antibiotic-inappropriate ARI diagnoses in baseline and intervention periods, adjusted for patient age, sex, and insurance status. Results Baseline rates were 43.5% and 42.8% for control and poster, respectively. During the intervention period, inappropriate prescribing rates increased to 52.7% for controls but decreased to 33.7% in the posted commitment letter condition. Controlling for baseline prescribing rates, we found that the posted commitment letter resulted in a 19.7 absolute percentage reduction in inappropriate antibiotic prescribing rate relative to control ( P = .02). There was no evidence of diagnostic coding shift, and rates of appropriate antibiotic prescriptions did not diminish over time. Conclusions and Relevance Displaying poster-sized commitment letters in examination rooms decreased inappropriate antibiotic prescribing for ARIs. The effect of this simple, low-cost intervention is comparable in magnitude to costlier, more intensive quality-improvement efforts. Trial Registration clinicaltrials.gov identifier:NCT01767064