study design

Trans-auricular vagus nerve stimulation to reduce perioperative pain and morbidity: protocol for a single-blind analyser-masked randomised controlled trial Amour B.U. Patel, Phillip P.W.M. Bibawy, Zehra Majeed, Weng Liang Gan, Gareth L. Ackland Background Established or acquired loss of...

One question that has been bugging my mind is whether studying the lowered tolerance to alcohol that is commonly reported in ME would yield insights into the pathophysiology of the disease. In the few studies that asked ME patients about their tolerance to alcohol, 60% to 2/3 of them report...

Background Despite earlier doubts, a string of recent successes indicates that if sample sizes are large enough, it is possible—both in theory and in practice—to identify and replicate genetic associations with common complex diseases. But human genome epidemiology is expensive and, from a...

R Jones, S Carley, M Harrison. An introduction to power and sample size estimation. Emerg Med J2003;20:453–458 The importance of power and sample size estimation for study design and analysis. OBJECTIVES 1. Understand power and sample size estimation. 2 Understand why power is an important...

The importance of estimating sample sizes is rarely understood by researchers, when planning a study. This paper aims to highlight the centrality of sample size estimations in health research. Examples that help in understanding the basic concepts involved in their calculation are presented...