Biomedical subjects

John M Neuhaus

Publications and source records attributed to John M Neuhaus.

6 recordsLinked to original sources

PubMed2005

Use of an embedded N-of-1 trial to improve adherence and increase information from a clinical study.

Withdrawal of participants from randomized trials can occur because of symptoms thought to be related to the study medicine, but the causal relationship between the study medicine and the symptoms is often unclear. Single-patient trials ("N-of-1 trials"), developed to identify optimal therapy for an individual patient in the clinical setting, may provide a means of resolving some of these dilemmas. We describe here the use of an N-of-1 study embedded within a placebo-controlled trial of saw palmetto for a participant who considered withdrawing because he believed the study medication caused an increase in his blood pressure. In this case, the N-of-1 study not only reassured the patient, who decided to remain in the study, but provided potentially useful new information regarding the study medication. Wider use of formal N-of-1 studies may be a valuable tool for improving adherence and determining whether observed side effects are caused by study medication in clinical trials.

Blood Pressure↗

PubMed2005

Screening sexually active adolescents for Chlamydia trachomatis: what about the boys?

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.

Adolescent↗

PubMed2004

Infant pulmonary function in a randomized trial of fetal tracheal occlusion for severe congenital diaphragmatic hernia.

Congenital diaphragmatic hernia (CDH) carries a high mortality risk secondary to pulmonary hypoplasia and respiratory failure. In experimental animals, fetal tracheal occlusion (TO) induces lung growth and morphologic maturation. We measured indicators of pulmonary function in 20 infants who were enrolled in a randomized trial of fetal TO as treatment for severe CDH [nine with conventional treatment (controls); 11 with TO]. We hypothesized that TO would improve lung function. At birth, the TO group had a lower mean gestational age (30.8 +/- 2.0 versus 37.4 +/- 1.0 wk; p=0.0002). All infants required assisted ventilation. Mortality did not differ between groups (64 versus 78%, TO and control, respectively; p=0.64). We measured respiratory mechanics at four study points: 1) first 24 h, 2) before CDH operative repair (5.9 +/- 2.2 d), 3) immediately after repair (7.0 +/- 2.2 d), and 4) before elective extubation (32.5 +/- 16.1 d). We calculated perioperative oxygenation index and alveolar-arterial oxygen difference to assess efficiency of pulmonary gas exchange. Data were analyzed by univariate and repeated measures techniques. Respiratory system compliance (Crs) was low. The rate of increase in Crs over the four study points was greater in the TO group than in control subjects. Crs in the TO group was significantly greater at study 2 (0.28 +/- 0.12 versus 0.17 +/- 0.04 mL.cm H2O(-1).kg(-1); p=0.02) and study 4 (0.93 +/- 0.45 versus 0.51 +/- 0.16 mL.cmH2O(-1).kg(-1); p=0.02). oxygenation index did not differ between groups, but alveolar-arterial oxygen difference was lower in the TO infants. We conclude that fetal TO for severe CDH results in modest improvements in neonatal pulmonary function that are of questionable clinical significance.

Administration, Inhalation↗

PubMed2004

To screen or not to screen: prevalence of C. trachomatis among sexually active asymptomatic male adolescents attending health maintenance pediatric visits.

This study estimated the prevalence of Chlamydia trachomatis (CT) among sexually active, asymptomatic, multiethnic adolescent males attending preventive health maintenance visits at pediatric clinics within a large health maintenance organization. First-void urines of sexually active 14-18-year-old males were screened for CT. The CT infection rate was 4% (27/711), 95% CI = 2.5%, 5.5%.

Adolescent↗

PubMed2002

Effect of a clinical practice improvement intervention on Chlamydial screening among adolescent girls.

CONTEXT: Chlamydia trachomatis infection is a serious public health concern that disproportionately affects adolescent girls. Although annual C trachomatis screening of sexually active adolescent girls is recommended by health professional organizations and is a Health Employer Data and Information Set (HEDIS) performance measure, this goal is not being met. OBJECTIVE: To test the effectiveness of a system-level, clinical practice improvement intervention designed to increase C trachomatis screening by using urine-based tests for sexually active adolescent girls identified during their routine checkups at a pediatric clinic. DESIGN, SETTING, AND PARTICIPANTS: A randomized cluster of 10 pediatric clinics in the Kaiser Permanente of Northern California health maintenance organization, where adolescent girls aged 14 to 18 years had a total of 7920 routine checkup visits from April 2000 through March 2002. INTERVENTION: Five clinics were randomly assigned to provide usual care and 5 to provide the intervention, which required that leadership be engaged by showing the gap between best practice and current practice; a team be assembled to champion the project; barriers be identified and solutions developed through monthly meetings; and progress be monitored with site-specific screening proportions. MAIN OUTCOME MEASURE: Chlamydia trachomatis screening rate for sexually active 14- to 18-year-old girls during routine checkups at each participating clinic. RESULTS: The population of adolescents was ethnically diverse with an average age of 15.4 years. Twenty-four percent of girls in the experimental clinics and 23% in the control clinics were sexually active. Of the 1017 patients eligible for screening in the intervention clinic, 478 (47%) were screened; of 1194 eligible for screening in the control clinic, 203 (17%) were screened. At baseline, the proportion screened was 0.05 (95% confidence interval [CI], 0.00-0.17) in the intervention and 0.14 (95% CI, 0.01-0.26) in the control clinics. By months 16 to 18, screening rates were 0.65 (95% CI, 0.53-0.77) in the intervention and 0.21 (95% CI, 0.09-0.33) in the control clinics (time period by study group interaction, F(6,60) = 5.33; P<.001). The average infection rate for the experimental clinics was 5.8% (23 positive test results out of 393 total urine tests and a total of 3986 clinic visits) vs 7.6% in controls (12 positive test results out of 157 tests and 3934 clinic visits). CONCLUSIONS: Implementation of this clinical practice intervention in a large health maintenance organization system is feasible, and it significantly increased the C trachomatis screening rates for sexually active adolescent girls during routine checkups.

Adolescent↗

PubMed2002

Analysis of clustered and longitudinal binary data subject to response misclassification.

Misclassified clustered and longitudinal data arise in studies where the response indicates a condition identified through an imperfect diagnostic procedure. Examples include longitudinal studies that use an imperfect diagnostic test to assess whether or not an individual has been infected with a specific virus. This article presents methods to implement both population-averaged and cluster-specific analyses of such data when the misclassification rates are known. The methods exploit the fact that the class of generalized linear models enjoys a closure property in the case of misclassified responses. Data from longitudinal studies of infectious disease will illustrate the findings.

Biometry↗