Letter to the Editor: Double-counting due to inadequate statistics leads to false-positive findings in "Effects of creatine supplementation on memory in healthy individuals: a systematic review and meta-analysis of randomized controlled trials".

Prokopidis et al have conducted a meta-analysis of randomized, placebo-controlled clinical trials to assess the effects of oral creatine supplementation on memory performance of healthy individuals. However, concerns were raised regarding the validity of their statistical analyses, which may have led to misleading conclusions. In this letter, we describe the statistical issue at hand and its potential implications.

Evidence for predictive validity of blood assays to evaluate individual radiosensitivity.

Purpose: An escalation in standard irradiation dose ensuring improved local tumor control is estimated, but this strategy would require the exclusion of the most sensitive individuals from treatment. Therefore, fast and reliable assays for prediction of the individual radiosensitivity are urgently required.

Methods And Materials: Seven parameters in lymphocytes of 40 patients with leukemia were analyzed before, during, and after total body irradiation (TBI) and in vitro X-ray irradiation.

Quantification of PCR products using microparticles and flow cytometry.

The analysis of genetic biomarkers has become an important tool in clinical diagnostics. This includes the identification of disease-related genetic alterations, the detection of pathogenic infective germs on DNA or RNA level and the quantification of the expression of marker genes indicating an altered physiological status. It has been previously described that the combination of polymerase chain reaction (PCR), microparticles and flow cytometry represents a universal platform technology for the routine analysis of such biomarkers.

Soluble Fas is increased in hyperthyroidism independent of the underlying thyroid disease.

In Hashimoto's thyroiditis, Fas-induced apoptosis is one of the mechanisms leading to cell destruction, whereas thyroid tissue in Graves' disease is prevented from it. The soluble form of the Fas molecule produced by alternative splicing prevents from apoptosis. We measured soluble Fas in the sera of 112 patients with Graves' disease, 21 patients with toxic goiter, and 24 patients with subclinical hyperthyroidism due to suppressive therapy with levothyroxine after near-total resection of the thyroid gland for nodular goiter.