Metastatic bone disease is increasing in association with ever-improving medical management of osteophylic malignant conditions. The precise timing of surgical intervention for secondary lesions in long bones can be difficult to determine. This paper aims to evaluate a classic scoring system. All radiographs were examined twice by three orthopaedic oncologists and scored according to the Mirels’ scoring system. The Kappa statistic was used for the purpose of statistical analysis. The results show agreement between observers (κ = 0.35–0.61) for overall scores at the two time intervals. Inter-observer agreement was also seen with subset analysis of size (κ = 0.27–0.60), site (κ = 0.77–1.0) and nature of the lesion (κ = 0.55–0.81). Similarly, low levels of intra-observer variability were noted for each of the three surgeons (κ= 0.34, 0.39, and 0.78, respectively). These results indicate a reliable, repeatable assessment of bony metastases. We continue to advocate its use in the management of patients with long bone metastases.
The confounding and aliasing scheme for fractional factorial split-plot designs with the units within each wholeplot arranged in rows and columns is described and illustrated. Isomorphism for this design type is described, together with a procedure which considers extensions of the concepts of wordlength patterns and letter patterns that can be used to test isomorphism between designs. Using in part this isomorphism testing procedure, a construction algorithm that may be used to obtain a complete set of such non-isomorphic two-level designs is described. Software based on this construction algorithm was used to obtain a complete set of non-isomorphic designs for up to five wholeplot factors, five Subplot factors and up to 64 runs, which is presented as a table of designs. To aid the experimenter in distinguishing between competing designs, the estimation capacity sequence for each design is presented.
There have been significant developments in the electronics industry over the past decade which have led to the development of a variety of electronic measuring devices that can be placed in packages to both record and save shock and vibration data related to shipment. Most of the earlier devices were purely mechanical in nature and used a paper graph or a visual indicator to quantify shock levels. There are many of these types of mechanical devices that are still being used today because of their low cost. This study was performed to determine the reliability and error for various types of commercial mechanical shock recorders and impact indicators. The results are presented in the form of mean per cent errors in measuring shock values. The study concluded that the Impact-O-Graph recorder measured shock values more accurately than the Impact Register and that the Omni-G, Mag 2000 and Shockranger were similar in accuracy and were better than the Shockwatch when used in a variety of packages judged to be typical for instrumented shipment.