Although the severity of haemophilic arthropathy is commonly assessed using established radiographic scoring systems, there is limited available information about their inter- and intra-observer reliability. The purpose of the present study was to establish the inter-observer reliability (IEOR) and intra-observer reliability (IAOR) of three different methods available for the classification of haemophilic arthropathy, including the Arnold and Hilgartner classification, a modification to the Arnold and Hilgartner system described by Luck et al., and the classification described by Pettersson et al. Antero-posterior and lateral radiographs of 54 haemophilic joints were included for the analysis. To determine the IEOR for each one of the three radiographic systems, the radiographs were randomly evaluated by four observers, including two orthopaedic surgeons, one orthopaedic resident and one haematologist. For the determination of IAOR, all four reviewers repeated the assessment in a similar fashion, after a period of at least 2 weeks. IEOR and IAOR for the three classification systems was established using kappa (kappa) statistics. A Spearman rank correlation was used to determine the similarities between each reviewer's own interpretative scales. The IEOR was low for the Arnold and Hilgartner system (kappa = 0.35, P < or = 0.001) and the Luck system (kappa = 0.38, P < or = 0.001), but even lower for the Pettersson system (kappa = 0.06, P = 0.1). For the Pettersson system, particularly low kappa values were observed for the presence or absence of osteoporosis (kappa = 0.11, P = 0.0027), enlarged epiphysis (kappa = 0.10, P = 0.0039), erosion of joint margins (kappa = 0.11, P = 0.0018), and joint deformity (kappa = 0.16, P = 0.00001). However, a relatively high Spearman rank correlation for all three scales [r(s) = 0.75 (P < 0.001) for Arnold and Hilgartner system, r(s) = 0.74 (P < 0.001) for the Luck system and r(s) = 0.81 (P < 0.001) for Pettersson system] indicated an overall, general agreement among the reviewers with regard to the severity of the haemophilic arthropathy. There was a moderate IAOR value for both, the Arnold and Hilgartner system (kappa = 0.57, P = 0.00001) and the Luck system (kappa = 0.62, P = 0.00001) with a low IAOR value for the Pettersson system [kappa = 0.22, P = 0.00001). Currently available radiographic scoring systems for haemophilic arthropathy have low inter- and intra-observer reliability rates. Improvements, either through education or modification of the scoring systems, are critical in an era where correlations between clinical and radiographic scores have received significant attention.

With the growing proliferation of Wafer-Level-Chip-ScalePackages (WLCSP), the target applications are increasingly focused on hand-held devices and consumer applications like cellular phones, pagers, PDA's etc. Packages in this family, like National Semiconductor's micro SMD package, have proven reliability in thermal cycling, humidity and bias testing, and are generally rated at moisture sensitivity level 1 (MSL-1). As applications continue to require more functionality in smaller packages, these package types will continue the growing trend of prevalence in the market-place.Typical handheld applications like the cellular phone applications result in several cycles of flexing during normal application. Some cellular handset manufacturers have started investigating the need to implement a 'Push Button Test' to simulate the effects of repeated deflection of the PCB immediately under the keypads. This paper describes and discusses the results of extensive flexural testing done to understand the effect of flexural testing on wafer level components mounted on a PCB. The PCB configuration used attempted to approximate the PCB configuration typically seen with cellular phone applications. Multiple locations of component placement were selected with reference to the point of maximum flexing as well as distance to the nearest rivet/bolt location. Other parameters varied included the PCB build-up structure, and the landing pad sizes on the PCB at the soldering locations.These experiments have shown a clear trend in terms of the superior solder joint strength achieved with an optimized solder joint shape, the importance of device location on the PCB to enhance life in flexural testing, and the impact of the overall size of the solder joint subjected to flexural testing. For all possible variations listed, based on a combination of the solder ball size, the correct pad size, and the location on PCB, there are positions on the PCB available which will surpass required test values. In case of limitations on some parameters, there is still a combination using the other factors that can create a solder joint strength that is able to withstand all requirements during flexural testing. IntroductionThe growth of wafer level packages has largely been driven by the requirements of portable electronics, predominated by applications like cellular phones and PDA's. These applications are human-interaction intensive; that is, a very large portion of the applications involve a manual input of a tactile manner. This introduces a variable element into the operation of these devices, since the manual input will vary in magnitude and time depending on the user.Besides the typical reliability and life-cycle tests traditionally carried out for electronic packages, which include mechanical tests like drop tests and bending tests, the additional

Package-on-Package (PoP) technology has been in production for commercial and portable electronic applications for many years. The key challenge for PoP in automotive applications is meeting the aggressive defect level requirements. The need for PoP has historically been driven by mobile and tablet applications and an increased demand for more processor and memory performance within smaller spaces. With the maturity and excellent historical performance of PoP technology used with TI OMAPTM processor products, PoP can now be introduced as a reliable packaging technology in the automotive industry. This paper will describe the work involved in the enablement of commercial PoP technology into the automotive industry. The challenges and requirements regarding package design, warpage performance, surface mount (SMT) characterization, and board-level reliability (BLR) performance will all be explained.