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Ratings given to the same item response may have a stronger correlation than those given to different item responses, especially when raters interact with one another before giving ratings. The rater bundle model was developed to account for such local dependence by forming multiple ratings given to an item response as a bundle and assigning fixed-effect parameters to describe response patterns in the bundle. Unfortunately, this model becomes difficult to manage when a polytomous item is graded by more than two raters. In this study, by adding random-effect parameters to the facets model, we propose a class of generalized rater models to account for the local dependence among multiple ratings and intrarater variation in severity. A series of simulations was conducted with the freeware WinBUGS to evaluate parameter recovery of the new models and consequences of ignoring the local dependence or intrarater variation in severity. The results revealed a good parameter recovery when the data-generating models were fit, and a poor estimation of parameters and test reliability when the local dependence or intrarater variation in severity was ignored. An empirical example is provided.

Many latent traits in the human sciences have a hierarchical structure. This study aimed to develop a new class of higher order item response theory models for hierarchical latent traits that are flexible in accommodating both dichotomous and polytomous items, to estimate both item and person parameters jointly, to allow users to specify customized item response functions, and to go beyond two orders of latent traits and the linear relationship between latent traits. Parameters of the new class of models can be estimated using the Bayesian approach with Markov chain Monte Carlo methods. Through a series of simulations, the authors demonstrated that the parameters in the new class of models can be well recovered with the computer software WinBUGS, and the joint estimation approach was more efficient than multistaged or consecutive approaches. Two empirical examples of achievement and personality assessments were given to demonstrate applications and implications of the new models.

The cutaneous lesions of incontinentia pigmenti classically evolve in stages, beginning with erythematous vesicular rash and bullae, followed by verrucose lesions, with an eventual macular pattern of splashed or whorled hyperpigmentation. We describe female twins presenting with the classic form of cutaneous expression. Ophthalmologic examination revealed abnormal vascular proliferations in the peripheral retinas in twin B. Several studies have confirmed linkage of familial incontinentia pigmenti to chromosome Xq28, with the factor VIII gene in Xq28 identified as the locus for incontinentia pigmenti. Two-hundred kilobases proximal to this locus, the gene for NEMO (NF-kappaB essential modulator)/IKKgamma (I kappaB kinase-gamma) has been mapped. We describe herein female twins with incontinentia pigmenti caused by a de novo mutation of this locus, as demonstrated by diagnostic polymerase chain reaction.

Background: Patent ductus arteriosus (PDA) is commonly found in very low-birthweight (VLBW) infants. The presence of respiratory distress syndrome (RDS) is also associated with increased frequency of significant PDA. Intravenous indomethacin has been used to treat and to prevent PDA in premature infants since 1976. However, concern remains regarding the safety of indomethacin, which affects renal, gastrointestinal and cerebral perfusion. Intravenous ibuprofen has recently been used to treat and to prevent PDA premature infants with PDA without reducing cerebral blood flow or affecting intestinal or renal hemodynamics. The aim of the present study is to compare intravenous ibuprofen and indomethacin with regard to efficacy and safety for the early treatment of PDA in preterm infants. Methods: A total of 63 preterm infants with RDS who had a birthweight of ≤1500 g and gestational age of ≤32 weeks, were enrolled in the present study. All patients were treated with nasal continuous positive airway pressure with additional oxygen supply in inspired air>30%, or with mechanical ventilation. The patients’ serum platelet counts were>100 000/uL, and serum creatinine values were