Delay in diagnosis and treatment of acute appendicitis (AA) results in an increased rate of perforation, postoperative morbidity, mortality and hospital length of stay. Several biochemical parameters ...including white blood cell (WBC) count, C-reactive protein (CRP), interleukin-6 (IL6) and Procalcitonin (PCT) have been used to further improve the clinical diagnosis of AA. The aim of this study was to assess the value of procalcitonin as a predictor of diagnosis and severity of appendicitis in order to improve the clinical decision making, since other studies have been unable to demonstrate a diagnostic value for PCT elevation in acute appendicitis.
One-hundred patients who underwent open appendectomy, including 75 men and 25 women with a mean age of 28 years were included in this study. Procalcitonin values were measured by an immunofluorescent method). Serum PCT>0.5 ng/ml was considered positive. The PCT serum values were measured in four different categories, including ˂0.5ng/ml, 0.5-2 ng/ml, 2-10ng/ml and more than 10ng/ml.
The sensitivity and specificity of PCT level measurement for acute appendicitis diagnosis were 44% and 100% respectively. The value of PCT increased with the severity of appendicitis and also with the presence of peritonitis and infection, at the site of surgery.
Procalcitonin measurement cannot be used as a diagnostic test for adult patients with acute appendicitis and its routine use in such patients is not cost effective and conclusive. Procalcitonin values can be used as a prognostic marker and predictor of infectious complications following surgery and it can help to carry out timely surgical intervention which is highly recommended in patients with PCT values more than 0.5ng/ml.
Risk of beta: Evidence from Prospect Theory Ali Saghafi; Roohollah Farhadi; Mohammad Taghi Taghavi Fard
مطالعات تجربی حسابداری مالی,
03/2015, Volume:
12, Issue:
45
Journal Article
Open access
According to Prospect Theory, Investors have different behaviors in theprofit and loss situations and indeed their trading behavior is different in bulland bear markets. This study uses quantile ...regression model (in differentquartiles) and OLS model to estimate beta of 180 firms. Results showed thatfirst, equity total risk (standard deviation) increase in Upper quartile andsecond, stocks beta changes in different quartiles and by moving fromquartile 0.25 to quartile 0.75, systematic risk (beta) increases significantly.Linear regression model and Quantile regression model show also thatunexpected variance can explain excess return at least similar to expectedvariance. The results can also be interpreted with both Insight of standardfinance and insight of behavioral finance. In standard finance area, riskreturnpositive relation that exists in upper quintiles is consistent with longrun growth of economy. Moreover, negative relation between return and riskin lower quintiles imply more uncertainty and as a result causing stockreturns to fall. In behavioral finance area, regime-dependent behavior ofslope coefficients is consistent with prediction of Prospect theory ofinvestor’s behaviors around the reference point.
