ROC curve analysis is often applied to measure the diagnostic accuracy of a biomarker. The analysis results in two gains: diagnostic accuracy of the biomarker and the optimal cut-point value. There are many methods proposed in the literature to obtain the optimal cut-point value. In this study, a new approach, alternative to these methods, is proposed. The proposed approach is based on the value of the area under the ROC curve. This method defines the optimal cut-point value as the value whose sensitivity and specificity are the closest to the value of the area under the ROC curve and the absolute value of the difference between the sensitivity and specificity values is minimum. This approach is very practical. In this study, the results of the proposed method are compared with those of the standard approaches, by using simulated data with different distribution and homogeneity conditions as well as a real data. According to the simulation results, the use of the proposed method is advised for finding the true cut-point.

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The aim of this study was to derive regression equations for estimating stature and further to estimate sex from four measured sternal lengths. This study included intact sterna from 65 males and 30 females, aged between 25 and 40 years, obtained during medico-legal autopsies. Stature and four sternal lengths, length of the manubrium (LM), length of the body (LB), length of the manubrium and body (LMB) and total sternal length, of each cadaver were measured. Stature and all measured sternal lengths were greater in males compared to females (p < 0.001). All sternal lengths were positively correlated with stature in sexes. LMB had the highest correlation coefficient in both males and females (correlation coefficient: 0.721 and 0.740, respectively). In both sexes, linear regression analysis for stature estimation revealed equations with the highest R (2) values when derived from LMB (R (2) = 0.521 for males and R (2) = 0.547 for females). On the other hand, only the multiple linear regression equation derived from the combination of the LB and LMB had the higher R (2) value (R (2) = 0.640) for stature estimation in females. Receiver-operating curve analysis for all measurements was statistically significant (p < 0.05 for all). These findings suggested that measured sternal lengths can be used for estimation of sex. However, LB and LMB measurements were found to be the most reliable sternal lengths for estimating sex with an accuracy rate of 90 %. Our results revealed that the sternum is a useful tool for estimating stature and sex when other skeletal bones are not available.

Whole-body FDG PET/CT has to be considered a useful method, especially in an early phase of the diagnostic workup of patients with carcinoma of an unknown primary syndrome, to optimize the management.

Objective: To evaluate the choroidal thickness in patients with multiple sclerosis (MS) using enhanced depth imaging optical coherence tomography (EDI-OCT). Methods: In this observational comparative study, 68 eyes of 34 MS patients and 60 eyes of 30 healthy subjects were evaluated. All participants underwent complete ophthalmologic examination and OCT scanning. Choroidal thickness measurements were performed at seven points. Results: The mean subfoveal choroidal thickness was reduced significantly in MS patients (310.71 ± 61.85 μm) versus healthy controls (364.85 ± 41.81 μm) (p < 0.001). The difference was also significant at all six measurement points (p < 0.001 for all). Choroidal thickness measurements revealed no significant difference between MS eyes with a prior optic neuritis (ON) history (MS ON) and those without ON history (MS non-ON). Subfoveal choroidal thickness did not correlate with retinal nerve fiber layer and Expanded Disability Status Scale score, but reduced choroidal thickness was associated with longer disease duration (r = -0.28, p = 0.019) in MS patients. Conclusion: In MS patients, choroidal structural changes occur both in MS ON and MS non-ON eyes. The decreased choroidal thickness might provide evidence to support a potential role of vascular dysregulation in the pathophysiology of MS.

Background In the absence of a real gold standard, comparative studies are still done on diagnostic methods for onychomycosis. There are only a few attempts using latent class analysis to determine the value of polymerase chain reaction in comparison to conventional methods. We aimed to determine the value of histological examination in such a way for the diagnosis of onychomycosis.Methods Potassium hydroxide mount (KOH), culture and histological examination with periodic acid-Schiff (PAS), and Gomori's methenamine silver (GMS) stains were done in 106 patients having clinically suspected toenail onychomycosis.Results KOH was positive in 74% of the patients; culture in 14%; PAS in 30%; and GMS in 66%. According to the results of the latent class analysis, culture and PAS were highly specific but poorly sensitive; KOH, highly sensitive but poorly specific; and GMS, both highly sensitive and specific.Conclusions Based on these results, we have proposed KOH as a screening test and GMS as a confirmatory test for the diagnosis of onychomycosis in our own practice.However, since positivity rates of different diagnostic methods vary widely in different centers, it is more suitable that every center should determine their own diagnostic strategy by evaluating their own results with latent class analysis.

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Measurement of arterial stiffness is a convenient, inexpensive and reliable method for predicting mortality in patients with advanced heart failure.