Background: Although observational evidence has suggested that the measurement of coronary artery calcium (CAC) may improve risk stratification for cardiovascular events and thus help guide the use of lipid-lowering therapy, this contention has not been evaluated within the context of a randomized trial. The Value of Imaging in Enhancing the Wellness of Your Heart (VIEW) trial is proposed as a randomized study in participants at low intermediate risk of future coronary heart disease (CHD) events to evaluate whether CAC testing leads to improved patient outcomes.
Purpose: To describe the challenges encountered in designing a prototypical screening trial and to examine the impact of uncertainty on power.
Methods: The VIEW trial was designed as an effectiveness clinical trial to examine the benefit of CAC testing to guide therapy on a primary outcome consisting of a composite of nonfatal myocardial infarction, probable or definite angina with revascularization, resuscitated cardiac arrest, nonfatal stroke (not transient ischemic attack (TIA)), CHD death, stroke death, other atherosclerotic death, or other cardiovascular disease (CVD) death. Many critical choices were faced in designing the trial, including (1) the choice of primary outcome, (2) the choice of therapy, (3) the target population with corresponding ethical issues, (4) specifications of assumptions for sample size calculations, and (5) impact of uncertainty in these assumptions on power/sample size determination.
Results: We have proposed a sample size of 30,000 (800 events), which provides 92.7% power. Alternatively, sample sizes of 20,228 (539 events), 23,138 (617 events), and 27,078 (722 events) provide 80%, 85%, and 90% power. We have also allowed for uncertainty in our assumptions by computing average power integrated over specified prior distributions. This relaxation of specificity indicates a reduction in power, dropping to 89.9% (95% confidence interval (CI): 89.8-89.9) for a sample size of 30,000. Samples sizes of 20,228, 23,138, and 27,078 provide power of 78.0% (77.9-78.0), 82.5% (82.5-82.6), and 87.2% (87.2-87.3), respectively.
Limitations: These power estimates are dependent on form and parameters of the prior distributions.
Conclusions: Despite the pressing need for a randomized trial to evaluate the utility of CAC testing, conduct of such a trial requires recruiting a large patient population, making efficiency of critical importance. The large sample size is primarily due to targeting a study population at relatively low risk of a CVD event. Our calculations also illustrate the importance of formally considering uncertainty in power calculations of large trials as standard power calculations may tend to overestimate power.
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http://dx.doi.org/10.1177/1740774512436882 | DOI Listing |
Mov Disord
January 2025
Department of Neurology, LMU University Hospital, Ludwig-Maximilians-Universität (LMU) München, Munich, Germany.
Background: The recent Movement Disorders Society (MDS)-progressive supranuclear palsy (PSP) diagnostic criteria conceptualized three clinical diagnostic certainty levels: "suggestive of PSP" for sensitive early diagnosis based on subtle clinical signs, "possible PSP" balancing sensitivity and specificity, and "probable PSP" highly specific for PSP pathology.
Objective: The aim of this study was to prospectively validate the criteria against long-term clinical follow-up and characterize the diagnostic certainty increase over time.
Methods: Patients with "possible PSP" or "suggestive of PSP" diagnosis and clinical follow-up were recruited in two German multicenter longitudinal observational studies (ProPSP and DescribePSP).
J Clin Med
December 2024
Pető András Faculty, Semmelweis University, 1125 Budapest, Hungary.
Cerebral palsy (CP) manifests with abnormal posture and impaired selective motor control, notably affecting trunk control and dynamic balance coordination, leading to inadequate postural control. Previous research has indicated the benefits of pulsed electromagnetic field (PEMF) therapy for various musculoskeletal and neurological conditions. Therefore, we conducted a randomized pilot study to assess the feasibility of our preliminary research design and examine the effect of the PEMF treatment among children with CP.
View Article and Find Full Text PDFJ Clin Med
December 2024
Molecular Biology Department, Surgery and Cardiovascular Biomedicine, National Institute of Cardiology Ignacio Chávez, Juan Badiano 1, Tlalpan, Mexico City 14080, Mexico.
Aortic valve calcification results from degenerative processes associated with several pathologies. These processes are influenced by age, chronic inflammation, and high concentrations of phosphate ions in the plasma, which contribute to induce mineralization in the aortic valve and deterioration of cardiovascular health. Environmental factors, such as wood smoke that emits harmful and carcinogenic pollutants, carbon monoxide (CO), and nitrogen oxide (NO), as well as other reactive compounds may also be implicated.
View Article and Find Full Text PDFJ Clin Med
December 2024
Department of Emergency Medicine, Chonnam National University Hospital, Gwangju 61469, Republic of Korea.
: Sudden cardiac death (SCD) poses a significant burden on the modern-day public health system; however, while our understanding of the underlying pathophysiology is still evolving and may not be complete, many insights are known and applied every day. Targeted prevention methods are continually being developed and refined. We conducted a systemic review and meta-analysis to identify a blood nutritional biomarker that can predict and screen population groups at high risk for cardiovascular disease mortality (CVD mortality) or SCD.
View Article and Find Full Text PDFJ Clin Med
December 2024
Department of Rehabilitation and Physiotherapy, Medical University of Lublin, 20-093 Lublin, Poland.
: Temporomandibular disorders (TMDs) represent a significant public health issue, among which masticatory muscle pain is the most common. Current publications increasingly indicate surface electromyography (sEMG) as an effective diagnostic tool for muscle dysfunctions that may be employed in TMDs recognition. The objective of this study was to establish reference ranges for TMDs patients with masticatory muscle pain and healthy individuals in the electromyographic Functional Clenching Index (FCI) for the temporalis muscles (TAs) and masseter muscles (MMs).
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