In clinical research, comparisons of the results from experimental and control groups are often encountered. The two-sample t-test (also called independent samples t-test) and the paired t-test are probably the most widely used tests in statistics for the comparison of mean values between two samples. However, confusion exists with regard to the use of the two test methods, resulting in their i...

BACKGROUND Quality of life is a concept, which in recent years is considered as a measure for health in chronic diseases such as kidney diseases. Complications of chronic diseases can affect the quality of life in children and their families over time. Therefore, empowerment programs are necessary to improve their quality of life. This study aimed to investigate the impact of the family empower...

The Symbol Digit Modalities Test (SDMT) and Digit Vigilance Test (DVT), both well-recommended attention tests for schizophrenia, are measures of switching and sustained attention, respectively. The purpose of this study was to investigate the test-retest reliability of the two attention tests in schizophrenia. A rater administered both tests on 147 participants with schizophrenia twice at a 1-w...

Results: All measurements were pooled and submitted to statistical analysis. In order to verify the inter-examiner systematic error a paired t-test was performed. Dahlberg ’s formula was used to estimate the casual error. For comparison purposes between Before and After stages, a paired t-test was done. For the comparison between mini-implant and Nance button groups, a Student t-test was applie...

Purpose To compare the lesion sizes of choroidal neovascularization (CNV) imaged with spectral-domain (SD) and swept-source (SS) optical coherence tomography angiography (OCTA) and measured using an automated detection algorithm. Methods Patients diagnosed with CNV were imaged by SD-OCTA and SS-OCTA systems using 3 × 3-mm and 6 × 6-mm scans. The complex optical microangiography (OMAGC) algori...

BACKGROUND Cocoa polyphenols have been shown to reduce stress in highly stressed, as well as normal healthy individuals, we wondered whether commercially available chocolate could reduce perceived stress in medical students or not, so we decided to conduct this study. METHODS Sixty students were divided into 3 groups (10 males + 10 females/group): i) Dark chocolate (DC) ii) Milk chocolate (MC...

Eight patients with ventricular extrasystoles are reported in whom coupling intervals of the extrasystoles to the proceding sinus beats were variable and in whom paired ventricular extrasystoles were occasionally seen. In all patients, paired ventricular extrasystoles were initiated only by comparatively late coupled ventricular extrasystoles. However, the interval between the first and the sec...

Objective:To study the effects of oral and intravenous maternal hydration in third trimester idiopathic or isolated oligohydramnios, and to determine the duration of actions. Design: Prospective clinical study. Setting:OB/GYN department, Benha Teaching Hospital, Benha, Egypt.; Patient(s):34 pregnant patients, about 35 weeks gestation, with idiopathic oligohydramnios. Intervention(s):acute oral ...

The one-sample paired t-test may be used to test whether the mean difference of two populations is greater than, less than, or not equal to a specific value. Because the t distribution is used to calculate critical values for the test, this test is often called the paired t-test. If the standard deviation of the differences is known, the normal distribution is used instead of the t distribution...

The role of vacuum mixing on the reduction of porosity and on the clinical performance of cemented total hip replacements remains uncertain. We have used paired femoral constructs prepared with either hand-mixed or vacuum-mixed cement in a cadaver model which simulated intra-operative conditions during cementing of the femoral component. After the cement had cured, the distribution of its poros...