Biomedical subjects

Paul Gallo

Publications and source records attributed to Paul Gallo.

6 recordsLinked to original sources

PubMed2006

Challenges in implementing adaptive designs: comments on the viewpoints expressed by regulatory statisticians.

This is a discussion of the following three papers appearing in this special issue on adaptive designs: 'FDA's critical path initiative: A perspective on contributions of biostatistics' by Robert T. O'Neill; 'A regulatory view on adaptive/flexible clinical trial design' by H. M. James Hung, Robert T. O'Neill, Sue-Jane Wang and John Lawrence; and 'Confirmatory clinical trials with an adaptive design' by Armin Koch.

Biometry↗

PubMed2006

Adaptive designs in clinical drug development--an Executive Summary of the PhRMA Working Group.

A PhRMA Working Group on adaptive clinical trial designs has been formed to investigate and facilitate opportunities for wider acceptance and usage of adaptive designs and related methodologies. A White Paper summarizing the findings of the group is in preparation; this article is an Executive Summary for that full White Paper, and summarizes the findings and recommendations of the group. Logistic, operational, procedural, and statistical challenges associated with adaptive designs are addressed. Three particular areas where it is felt that adaptive designs can be utilized beneficially are discussed: dose finding, seamless Phase II/III trials designs, and sample size reestimation.

Biomedical Research↗

PubMed2003

VALsartan In Acute myocardial iNfarcTion (VALIANT) trial: baseline characteristics in context.

BACKGROUND: The VALsartan In Acute myocardial iNfarcTion (VALIANT) trial compared outcomes with: (1) angiotensin-converting enzyme inhibition (ACEI) with the reference agent captopril; (2) angiotensin-receptor blockade (ARB) with valsartan; or (3) both in patients with heart failure (HF) and/or left ventricular systolic dysfunction (LVSD) after myocardial infarction (MI). AIMS: a goal of this active-control trial was to simulate conditions that would lead current practitioners to use ACEIs. Thus, we compared characteristics of VALIANT patients with those of patients in placebo-controlled trials that established ACEIs as standard treatment. METHODS AND RESULTS: We collected demographic, clinical, medication and imaging information from 14703 patients in 24 countries. This high-risk population was a median 65.8 years old, and 31.1% were female. Most (51.8%) showed imaging evidence of LVSD at enrollment. Most (72%) had Killip class>/=II HF. Patients received evidence-based therapies at rates similar to those of contemporary MI trials and at an improved rate compared with prior placebo-controlled ACEI trials. CONCLUSION: VALIANT represents the largest globally representative cohort enrolled with HF and/or LVSD after MI. Patients were similar to those in placebo-controlled ACEI trials while reflecting improvements in evidence-based care. With enrollment complete, VALIANT is poised to define the optimal strategy for renin-angiotensin system blockade after MI to improve cardiovascular outcomes.

Aged↗

PubMedDate not supplied

Operational challenges in adaptive design implementation.

Implementation of adaptive clinical trial designs raises challenges with regard to the processes by which accruing trial data is analyzed, reviewed, and acted upon. In line with current monitoring conventions, it should be viewed that inappropriate knowledge of interim results can raise concerns regarding maintaining trial integrity and interpretability of results. Here we discuss issues related to these processes in adaptive trials, and point out distinctions versus other more familiar monitoring situations. One topic involves the composition of the group of individuals who will have access to interim results in order to recommend adaptations. We discuss operational models for data review by this group; one question addressed is whether in adaptive trials a role in this process for a representative of the study sponsor could at times be warranted, and might be justified if adequate protections are in place. Another issue involves whether adaptations made based upon interim data can convey to observers an amount of information about the results, which could rise to a level of concern. We consider whether different types of adaptations might be more or less problematic with regard to this issue, and recommend steps that might be considered to mitigate this concern.

Clinical Trials as Topic↗

PubMedDate not supplied

Prehospital cardiac arrest in a paramedic first-responder system using the Utstein style.

OBJECTIVES: To describe the characteristics of patients found to have cardiac arrest and to evaluate the characteristics predictive of survival after cardiac arrest in a paramedic first-responder model. METHODS: All patients who suffered out-of-hospital cardiac arrest in the city of Reading, Ohio, from January 1998 to December 2003 were recorded in the Utstein style. The number and incidence rate of witnessed arrests, initial rhythms, rate of bystander cardiopulmonary resuscitation (CPR), and 30-day mortality rate were retrospectively collected. Demographics, time to hospital, and response times were evaluated as predictors of survival. RESULTS: Of those patients initially found to be in cardiac arrest, 14.3% were discharged alive. Witnessed arrests were more likely to result in live discharge of the patient. Whether bystander CPR was performed was not found to affect survival, nor was initial rhythm, although no patients initially found in asystole were discharged alive. No demographic characteristics or response times were predictive of survival. CONCLUSION: The rates of survival in this paramedic first-response system are favorable compared with basic emergency medical technician first-response systems. Further study using direct comparison methodology is warranted to confirm these findings.

Aged↗

PubMedDate not supplied

Evaluating an emergency medical services-initiated nontransport system.

OBJECTIVE: To evaluate both factors predicting nontransport and mortality rates in an emergency medical services system with a nontransport policy. METHODS: We reviewed data from 1,581 transported and nontransported patients from October 2001 to July 2003. Patients who refused transport against medical advice were excluded. Extracted data included demographics, run characteristics, chief complaint, and clinical impression. Transported and nontransported patients were compared using Mann-Whitney U or chi-square tests. Logistic regression identified factors predictive of nontransport. A Social Security Death Index search determined 30-day mortality. RESULTS: A total of 1,501 runs involving 1,059 patients were included. Median age was 60 years (range, 0-97 years). A total of 427 (40.4%) were male; 107 (10.2%) were nonwhite. Older patients were more likely to be transported (odds ratio, 1.03; confidence interval, 1.02-1.03). Race, frequency of calls, mutual aid, or time of day did not significantly influence probability of transport. Patients with cardiovascular, respiratory, and gastrointestinal complaints were more likely to be transported than those with other conditions (P < 0.005); patients with endocrine, trauma, and miscellaneous complaints were less likely to be transported (P < 0.003). Patients with renal, obstetrics/gynecology, and hema matology/oncology were complaints all transported. Mortality was 4.9% (confidence interval, 3.9%-6.2%) for transported patients and 1.0% for those not transported (confidence interval, 0.2%-3.7%). CONCLUSIONS: Age is a determinant when deciding on transporting patients. Patients with complaints with potentially higher acuity were transported most often. Only two nontransported patients died within 30 days, although it is unknown whether initial transport would have changed their mortality. Our data suggest that emergency medical services-initiated nontransport is influenced only by age and chief complaint and may not result in significant mortality.

Adolescent↗