This article gives an overview of sample size calculations for parallel group and cross‐over
studies with Normal data. Sample size derivation is given for trials where the objective is to …

Sample size calculations are now mandatory for many research protocols, but the ones
useful in common situations are not all easily accessible. This paper outlines the ways of …

Background Randomised controlled trials (RCTs) are the gold standard assessment for
health technologies. A key aspect of the design of any clinical trial is the target sample size. …

… 288 SA Julious … given by Julious [6]. This high plausible value could be estimated using
the upper one-tailed 95th percentile for the variance from the formula … 290 SA Julious …

… The first was proposed by Browne 10 and will be referred to as the upper confidence limit
(UCL) approach and the second by Julious and Owen 9 which will be referred to as the non-…

… While Julious [9] highlights that a sample size that is too small will have an imprecisely
estimated variance, which could impact on the design of a future definitive study. …

… Julious and Swank [23] suggest a method of calculating a probability of success for different
… This method has previously been described by Julious et al. [22] for binary and Normal …

Background Substantial amounts of public funds are invested in health research worldwide.
Publicly funded randomised controlled trials (RCTs) often recruit participants at a slower …

… Julious is a professor of medical statistics at the University of Sheffield and has over 30
years of applied research experience. His research interests, in both an academic and …

This study was undertaken to investigate the reported association between Chlamydia
pneumoniae and Mycoplasma pneumoniae infection and the expression of asthma-related …