Multiple Imputation for General Missing Data Patterns in the Presence of High-dimensional Data.

Multiple imputation (MI) has been widely used for handling missing data in biomedical research. In the presence of high-dimensional data, regularized regression has been used as a natural strategy for building imputation models, but limited research has been conducted for handling general missing data patterns where multiple variables have missing values. Using the idea of multiple imputation by chained equations (MICE), we investigate two approaches of using regularized regression to impute missing values of high-dimensional data that can handle general missing data patterns.

Door to Intravenous Tissue Plasminogen Activator Time and Hospital Length of Stay in Acute Ischemic Stroke Patients, Georgia, 2007-2013.

Background: Ischemic stroke patients benefit most from intravenous thrombolysis when they receive the treatment as quickly as possible after symptom onset. Hospitals participating in the Georgia Coverdell Acute Stroke Registry reduced the time from patient arrival to administration of intravenous tissue plasminogen activator. This study evaluates the benefit of reducing door-to-treatment (DTT) time as measured by hospital length of stay (LOS).

Administrative data linkage to evaluate a quality improvement program in acute stroke care, Georgia, 2006-2009.

Introduction: Tracking the vital status of stroke patients through death data is one approach to assessing the impact of quality improvement in stroke care. We assessed the feasibility of linking Georgia hospital discharge data with mortality data to evaluate the effect of participation in the Georgia Coverdell Acute Stroke Registry on survival rates among acute ischemic stroke patients.

Methods: Multistage probabilistic matching, using a fine-grained record integration and linkage software program and combinations of key variables, was used to link Georgia hospital discharge data for 2005 through 2009 with mortality data for 2006 through 2010.

Parathyroid hormone levels in pubertal uremic adolescents treated with growth hormone.

We have previously described severe hyperparathyroidism during the pubertal growth spurt in three uremic adolescents treated with recombinant human growth hormone (rhGH). Here we investigate the possible role of puberty in the genesis of hyperparathyroidism during rhGH treatment of a large cohort of patients. Data from 67 uremic patients treated with rhGH from five Italian pediatric nephrology centers were retrospectively recorded every 3 months starting 1 year before rhGH administration.