MSCs were harvested and isolated from the bone marrow of male pigs as described elsewhere

The paper explains how the data are collected, the steps followed in obtaining the sample, preparation of the sample, as well as the tests carried out. All this information is presented in a systematic manner with subheadings for each subsection thereby making it easy for the reader to replicate the experiment. In instances where detailed explanations are missing, the authors cite the source of their procedure. In addition, the materials and equipment used are adequately described. However, it is difficult to decide the appropriateness of the sampling method as there is no mention of the number of samples used. Under the subheading ‘cell culture studies,’ the authors indicate “MSCs were harvested and isolated from the bone marrow of male pigs as described elsewhere” (Tran et al. 2010, p. 9483). It is not clear how many pigs are used to obtain the mesenchymal stem cells. The article clarifies the kind of data collected. For example, in the population doubling time assay, the experimenters record the average time taken for the number of mesenchymal stem cells to increase twofold. Overall, the authors are meticulous in their description of measurements such as time (minutes, hours and days), temperature (degrees centigrade) and concentrations (micromoles, millimoles, micrograms per millilitre and so on).