Psychometric Properties and Convergent Validity of the Chinese Version of the Rosenberg Self-Esteem Scale.

The present study used the Rasch rating scale model (RSM) to reassess the psychometric properties of the Chinese version of Rosenberg self-esteem scale (RSES) among 501 Grade 10 students in Taiwan. The reliability, dimensionality, and differential item functioning were examined. The dimensionality assumption was met after excluding item 8 ("I wish I could have more respect for myself.

Latent profiles of stress and their relationships with depression and problematic Internet use among college freshmen.

As noted in previously published literature, college students frequently experience academic stress, financial stress, and the stresses caused by intimate, peer, and parent-adolescent relationships. The present study uses latent profile analysis to identify stress profiles based on the aforementioned five stressors among 430 college freshmen. Thereafter, we compare the levels of depression and problematic Internet use (PIU) among the different profile groups and investigate whether background variables could predict each latent stress group.

Impulsivity as a precedent factor for problematic Internet use: How can we be sure?

Previous research has suggested that problematic Internet use (PIU) is associated with impulse control disorder. Although researchers have suggested that impulsivity is a risk factor for PIU, the literature lacks longitudinal evidence on the relationship between impulsivity and PIU. We aimed to use a cross-lagged analytic framework to identify temporal order effects and hypothesised that impulsivity was the precedent factor for PIU.

Cognitive ability, academic achievement and academic self-concept: extending the internal/external frame of reference model.

Background: Marsh's internal/external (I/E) frame of reference model depicts the relationship between achievement and self-concept in specific academic domains. Few efforts have been made to examine concurrent relationships among cognitive ability, achievement, and academic self-concept (ASC) within an I/E model framework.

Aim: To simultaneously examine the influences of domain-specific cognitive ability and grades on domain self-concept in an extended I/E model, including the indirect effect of domain-specific cognitive ability on domain self-concept via grades.

Refining enamel thickness measurements from B-mode ultrasound images.

Dental erosion has been growing increasingly prevalent with the rise in consumption of heavy starches, sugars, coffee, and acidic beverages. In addition, various disorders, such as Gastroenterological Reflux Disease (GERD), have symptoms of rapid rates of tooth erosion. The measurement of enamel thickness would be important for dentists to assess the progression of enamel loss from all forms of erosion, attrition, and abrasion.

simpolycat: an SAS program for conducting CAT simulation based on polytomous IRT models.

A real-data simulation of computerized adaptive testing (CAT) is an important step in real-life CAT applications. Such a simulation allows CAT developers to evaluate important features of the CAT system, such as item selection and stopping rules, before live testing. SIMPOLYCAT, an SAS macro program, was created by the authors to conduct real-data CAT simulations based on polytomous item response theory (IRT) models.

Fractal dimension analysis of periapical reactive bone in response to root canal treatment.

Objective: Mathematical morphology and box counting were used to extract trabecular pattern and to evaluate changes of reactive bone following root canal treatment.

Study Design: Periapical radiographs were digitized and processed with mathematical morphology operations known as skeletonization. The trabecular patterns resulting from this skeletonization process were further analyzed with fractal dimension (FD) analysis using the box-counting method.

Digital imaging analysis with mathematical morphology and fractal dimension for evaluation of periapical lesions following endodontic treatment.

Objective: To see if a method for digitizing trabecular pattern of bone could be used to quantitatively evaluate changes in bone pattern following endodontic treatment of teeth with periapical osteolytic lesions.

Study Design: Periapical radiographs were digitized and further processed with mathematical morphology operations known as skeletonization. The trabecular patterns resulting from this skeletonization process were further analyzed with fractal dimension analysis using box-counting.

A pilot study applying digital radiography for estimating ratio of supported single-root surface area.

Background: The prognosis of a tooth with periodontitis is affected by the amount of supporting bone. A key factor in retaining a tooth is the ratio of supported root surface. Currently, root surfaces cannot be accurately measured using conventional dental radiographs, which only measure the length of bone support on proximal surfaces.

Enhanced speed and precision of measurement in a computer-assisted digital cephalometric analysis system.

The computer-assisted digital cephalometric analysis system (CADCAS) may reduce the time required for cephalometric analysis, especially for taking measurements. Aimed at estimating the time saved by using CADCAS, we measured the time needed by a clinician to perform the analysis in a traditional manner. We also sought to verify the accuracy achieved by traditional cephalometric analysis by exploring the disagreement between manual measurements and those generated by CADCAS.

Accuracy of supported root ratio estimation from projected length and area using digital radiographs.

Background: The purpose of this study was to evaluate the accuracy of supported single-root surface ratio estimated from the length and projected area of the tooth, using digital dental radiographs.

Methods: Eight extracted, single-root teeth were three-dimensionally digitized using a contact technique for surface area measurement. The data were then processed using engineering application software and length, projection area, and true surface area of the root at a designated length were obtained.

The effects of differences in landmark identification on the cephalometric measurements in traditional versus digitized cephalometry.

The aim of this study was to explore the effects of differences in landmark identification on the values of cephalometric measurements on digitized cephalograms in comparison with those obtained from original radiographs. Ten cephalometric radiographs were randomly selected from orthodontic patients' records. Seven orthodontic residents identified 19 cephalometric landmarks on the original radiographs and digitized images.

Calculation of simplified single-root surface area from simulated X-ray projection.

Background: The prognosis of a tooth affected by periodontitis might depend on the amount of bone remaining around the root surface. The surface area of a single tooth root relates to a simulated x-ray projection.

Methods: The aim of the study was to determine root surface area from radiographs.