many empirical papers have applied a semi-parametric two-stage procedure named tobit model to investigate the sources of inefficiency in different industries over the last two decades. using this approach in small samples has recently been criticized for a possible bias in its results. in very recent papers simar and wilson (2007) have tackled this problem by suggesting an alternative bootstrap...

OBJECTIVES A minimally invasive approach is considered the treatment of choice for gallbladder stones. We report our experience with the treatment of choledocholithiasis. METHODS From January 1993 to December 2002, 3118 patients underwent minimally invasive surgery for symptomatic gallstones, 2681 for gallbladder stones and 437 (14%) for cholecysto-choledocholithiasis. RESULTS We performed ...

Despite significant advances in laparoscopic technique and technologies, laparoscopic Urologic surgery remains technically demanding regarding various surgical steps including the challenge of specimen retrieval and extraction, whether to install a drainage system and the best option for wound closure. Laparoscopic specimen entrapment and extraction occurs at what is falsely considered the ″end...

Total knee arthroplasty (TKA) is a rewarding procedure in patients with hemophilia and end stage knee hemophilicarthropathy. However, this procedure might be associated with complications such as infection. There periprostheticjoint infection in patients with hemophilia is very well known, though we are not aware of any previous report on Brucellainfection in this group of patients. Here, we re...

Stages of growth models have been used widely in both organizational research and information technology management research. However, stages of growth models are criticized for lack of empirical validity. This paper develops a survey instrument to empirically validate a knowledge management technology stage model. The survey instrument has several parts that enable cross-examination of respons...

Bilateral rotator cuff tears requiring repair are not uncommon. Typically, these tears have been treated with staged surgeries. However, in appropriately selected cases, single-stage repair is preferable because it reduces costs, the number of admissions, total hospitalization, and rehabilitation time. It can also reduce patient suffering by providing relief with a single procedure. The authors...

Comparison of two hazard rates is important in applications related to times to occurrence of a specific event. Conventional comparison procedures, such as the logrank, Gehan-Wilcoxon, and Peto-Peto tests, are powerful only when the two hazard rates do not cross each other. Because crossing hazard rates are common in practice, a number of procedures have been proposed in the literature for comp...

Designing an efficient sampling scheme for a rare and clustered population is a challenging area of research. Adaptive cluster sampling, which has been shown to be viable for such a population, is based on sampling a neighborhood of units around a unit that meets a specified condition. However, the edge units produced by sampling neighborhoods have proven to limit the efficiency and applicabili...