Dennis D. Cox

Cost comparison between bilateral simultaneous, staged, and unilateral total joint arthroplasty

A hospital-based computer system was used to compare the inpatient costs of performing bilateral simultaneous sequential, staged, and unilateral total hip and knee arthroplasties. Bilateral simultaneous sequential total knee arthroplasty was 36% less costly than 2 unilateral total knee arthroplasties. Bilateral simultaneous sequential total hip arthroplasty saved 25% over the costs of performing 2 unilateral hip arthroplasties. Prosthetic costs range between 28% and 43% of the total costs of hospitalization. There was a significant correlation between hospital length of stay, morbidity, and total costs, but no correlation with patient age and sex except in the unilateral knee patients. Bilateral simultaneous sequential joint arthroplasty can save more than

Combined reflectance and fluorescence spectroscopy for in vivo detection of cervical pre-cancer

10,000 for each total knee patient and more than

Multivariate Smoothing Spline Functions

8,000 for each total hip patient.

Optimal excitation wavelengths for discrimination of cervical neoplasia

Optical technologies, such as reflectance and fluorescence spectroscopy, have shown the potential to provide improved point-of-care detection methods for cervical neoplasia that are sensitive, specific, and cost-effective. Our specific goals are to analyze the diagnostic potential of reflectance and fluorescence spectra, alone and in combination, to discriminate normal and precancerous cervical tissue in vivo and to identify which classification features contain significant diagnostic information. Reflectance spectra are measured at four source-detector separations and fluorescence emission spectra are measured at 16 excitation wavelengths, from 324 sites in 161 patients. These 20 spectral features are permuted in all possible combinations of one, two, and three; and classification algorithms are developed to evaluate the diagnostic performance of each combination. Algorithms based on fluorescence spectra alone yield better diagnostic performance than those based on reflectance spectra alone. The combination of fluorescence and reflectance do not significantly improve diagnostic performance compared to fluorescence alone, except in the case of discriminating high-grade precancers from columnar normal tissue. In general, fluorescence emission spectra at 330- to 360-nm and 460- to 470-nm excitation provide the best diagnostic performance for separating all pairs of tissue categories.

A smoothing spline based test of model adequacy in polynomial regression

Given data

Inpatient Cost of Primary Total Joint Arthroplasty

z_i = g(t_i ) + \varepsilon _i , 1 \leqq i \leqq n

Accuracy of Colposcopy in the Diagnostic Setting Compared With the Screening Setting

, where g is the unknown function, the

Effect of probe pressure on cervical fluorescence spectroscopy measurements

t_i

Primary noncemented total hip arthroplasty in patients with ankylosing spondylitis. Clinical and radiographic results at an average follow-up period of 6 years.

are known d-dimensional variables in a domain

Model-based analysis of reflectance and fluorescence spectra for in vivo detection of cervical dysplasia and cancer

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