Search results for "Randomization"

Efficacy of Selected Electrical Therapies on Chronic Low Back Pain: A Comparative Clinical Pilot Study

2017

Background: In the currently available research publications on electrical therapy of low back pain, generally no control groups or detailed randomization were used, and such studies were often conducted with relatively small groups of patients, based solely on subjective questionnaires and pain assessment scales (lacking measurement methods to objectify the therapeutic progress). The available literature also lacks a comprehensive and large-scale clinical study. The purpose of this study was to assess the effects of treating low back pain using selected electrotherapy methods. The study assesses the influence of individual electrotherapeutic treatments on reduction of pain, improvement of …

2019

Active aging has been established as a policy goal for aging societies. We define active aging at the individual level as striving for elements of well-being through activities in relation to a person’s goals, functional capacities and opportunities. Increasing evidence suggests that any meaningful activity is beneficial for different aspects of well-being in older people. The aim of the present randomized controlled trial is to test the feasibility and effectiveness of a one-year community-based intervention on active aging. The AGNES intervention aims at increasing older peoples’ participation in self-selected valued activities. The proposed study is a two-arm single-blinded randomized co…

Prevalence of nocturnal asthma in a general population sample: determinants and effect of aging.

2000

Nocturnal asthma (NA) is important because of clinical and prognostic implications. Previous data on prevalence may be overestimated, because they are derived from selected series. Observations on monitoring of peak expiratory flow in elderly asthmatics suggested that prevalence of NA may increase with age. This study was designed to estimate the prevalence of NA-related symptoms in a sample drawn from a general population and evaluate the role of aging. Subjects (1,100, mean age 41.9, SD 22.8 years) were randomly selected from the lists of seven general practitioners. A questionnaire on nighttime and morning NA-associated symptoms was used and frequency of occurrence was rated as never, so…

Diuretic vs. placebo in intermediate-risk acute pulmonary embolism: a randomized clinical trial

2022

Abstract Aims The role of diuretics in patients with intermediate-risk pulmonary embolism (PE) is controversial. In this multicentre, double-blind trial, we randomly assigned normotensive patients with intermediate-risk PE to receive either a single 80 mg bolus of furosemide or a placebo. Methods and results Eligible patients had at least a simplified PE Severity Index (sPESI) ≥1 with right ventricular dysfunction. The primary efficacy endpoint assessed 24 h after randomization included (i) absence of oligo-anuria and (ii) normalization of all sPESI items. Safety outcomes were worsening renal function and major adverse outcomes at 48 hours defined by death, cardiac arrest, mechanical ventil…

Planning and Analysis of Trials Using a Stepped Wedge Design: Part 26 of a Series on Evaluation of Scientific Publications

2019

Background The stepped-wedge design (SWD) of clinical trials has become very popular in recent years, particularly in health services research. Typically, study participants are randomly allotted in clusters to the different treatment options. Methods The basic principles of the stepped wedge design and related statistical techniques are described here on the basis of pertinent publications retrieved by a selective search in PubMed and in the CIS statistical literature database. Results In a typical SWD trial, the intervention is begun at a time point that varies from cluster to cluster. Until this time point is reached, all participants in the cluster belong to the control arm of the trial…

SEQUENTIALLY ADJUSTED RANDOMIZATION TO FORCE BALANCE IN CONTROLLED TRIALS WITH UNKNOWN PREVALENCE OF COVARIATES: APPLICATION TO ALCOHOLISM RESEARCH

2005

In treatment outcome studies with small to medium sample sizes (n200), the balance of groups with regard to important factors, which sometimes occur at low prevalence, is indispensable for adequate interpretation. This study tested a method for use in clinical alcoholism research, an uncomplicated procedure for satisfactory randomization of patients to different treatments, taking into account relevant background variables.An easily applicable modification of Efron's biased coin method for the randomization of treatments within strata of unknown but low prevalence was compared with the original approach and alternative methods by computer simulation (10,000 runs). An application example for…

Covariate-constrained Randomization Routine for Achieving Baseline Balance in Cluster-randomized Trials

2017

In cluster-randomized trials, groups or clusters of individuals, rather than individuals themselves, are randomly allocated to intervention or control. In this article, we describe a new command, ccrand, that implements a covariate-constrained randomization procedure for cluster-randomized trials. It can ensure balance of one or more baseline covariates between trial arms by restriction to allocations that meet specified balance criteria. We provide a brief overview of the theoretical background, describe ccrand and its options, and illustrate it using an example.

Causal Effects of Body Mass Index on Airflow Obstruction and Forced Mid-Expiratory Flow: A Mendelian Randomization Study Taking Interactions and Age-…

2021

Obesity has complex links to respiratory health. Mendelian randomization (MR) enables assessment of causality of body mass index (BMI) effects on airflow obstruction and mid-expiratory flow. In the adult SAPALDIA cohort, recruiting 9,651 population-representative samples aged 18–60 years at baseline (female 51%), BMI and the ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC) as well as forced mid-expiratory flow (FEF25–75%) were measured three times over 20 follow-up years. The causal effects of BMI in childhood and adulthood on FEV1/FVC and FEF25–75% were assessed in predictive (BMI averaged over 1st and 2nd, lung function (LF) averaged over 2nd and 3rd fol…

Birth weight, adult weight, and cardiovascular biomarkers : Evidence from the Cardiovascular Young Finns Study

2021

This study quantifies the causal effect of birth weight on cardiovascular biomarkers in adulthood using the Cardiovascular Risk in Young Finns Study (YFS). We apply a multivariable Mendelian randomization (MVMR) method that provides a novel approach to improve inference in causal analysis based on a mediation framework. The results show that birth weight is linked to triglyceride levels (β = −0.294; 95% CI [−0.591, 0.003]) but not to low-density lipoprotein (LDL) cholesterol levels (β = 0.007; 95% CI [−0.168, 0.183]). The total effect of birth weight on triglyceride levels is partly offset by a mediation pathway linking birth weight to adult BMI (β = 0.111; 95% CI [−0.013, 0.234]). The nega…

Photobiomodulation Therapy in the Management of Burning Mouth Syndrome: Morphological Variations in the Capillary Bed

2020

Burning mouth syndrome (BMS) is an idiopathic condition that manifests itself primarily with the onset of a burning sensation. The aim of this research was to perform photobiomodulation therapy (PBM) using a diode laser on the oral mucosa of BMS patients, followed by an objective evaluation of the morphological changes in the vascular bed underlying the mucosa using polarized light videocapillaroscopy. A group of 40 patients were included in the study. The patients were randomly divided into two groups (using simple randomization) as follows: 20 patients were assigned to the laser group and 20 patients were assigned to the placebo group. Each patient of the laser group received eight irradi…