The architectural and structural analysis of Delaire was developed to evaluate complex craniofacial structures without relating the individual to a so-called normal or average group. This analysis is especially valuable in two regards: first, this analysis is based upon mutual balance of the cranial and facial structures; second, statistical averages are avoided. But , the problem that causes fault in using this analysis is difficult identification of location of its landmarks and its influence on acquired results. The main goal of this study was evaluation of the repeatability of Delaire cephalometric analysis. Forty lateral cephalograms of patients aged 17-30 that who had no experience of previous surgical or orthodontic treatment with no history of injury to craniofacial structures were selected. The cephalograms were traced ( 5 landmarks: M, FM, Pts, CT, Clp) twice by two observers separately with an interval approximately 40 days between replicate tracings. Both observers registered the X and Y co-ordinate values of each landmark for subsequent statistical analysis. The results of this study showed that statistically significant differences existed for landmarks FM and Clp in first observer and for Pts in second observer for X co-ordinate values and there were no statistically significant intra-observer error for Y co-ordinate values. There was no statistically inter- observer error too. In summary, we concluded that there is desirable level of inter-observer repeatability in landmark identification in Delaire analysis but there is statistically significant intra-observer error in landmark identification in this analysis that maybe due to low experience of observer in this regard.

Purpose: To determine the accuracy of photorefraction and autorefraction as compared to cycloautorefraction and to detect the repeatability of photorefraction.Methods: This diagnostic study included the right eyes of 86 children aged 7-12 years. Refractive status was measured using photorefraction (PlusoptiX SO4, GmbH, Nurnberg, Germany) and autorefraction (Topcon RM800, USA) with and without cycloplegia. Photorefraction for each eye was performed three times to assess repeatability.Results: The overall agreement between photorefraction and cycloautorefraction was over 81% for all refractive errors. Photorefractometry had acceptable sensitivity and specificity for myopia and astigmatism. There was no statistically significant difference considering myopia and astigmatism in all comparisons, while the difference was significant for hyperopia using both amblyogenic (P=0.006) and nonamblyogenic criteria (P=0.001). A myopic shift of 1.21 diopter (D) and 1.58 D occurred with photorefraction in nonamblyogenic and amblyogenic hyperopia, respectively. Using revised cut-off points of+1.12 D and+2.6 D instead of+2.00 D and+3.50 D improved the sensitivity of photorefractometry to 84.62% and 69.23%, respectively. The repeatability of photorefraction for measurement of myopia, astigmatism and hyperopia was acceptable (intra-cluster correlation [ICC]: 0.98, 0.94 and 0.77, respectively). Autorefraction results were significantly different from cycloautorefraction in hyperopia (P<0.0001), but comparable in myopia and astigmatism. Also, noncycloglegic autorefraction results were similar to photorefraction in this study.Conclusion: Although photorefraction was accurate for measurement of myopia and astigmatism, its sensitivity for hyperopia was low which could be improved by considering revised cut-off points.Considering cut-off points, photorefraction can be used as a screening method.

Background and Aim: Because of high incidence of hand injuries and the need for a quantitative method that provides measures of patient improvement in treatment period, a precise and easy-to-apply quantitative procedure is necessary. As a first step in validating of such a method, the intersession repeatability of quantified measures was assessed in this study.Materials and Methods: Measurement of hand drawing skills by drawing circle shape in two speeds (preferred and maximum) and spiral shape just in a preferred voluntary speed with two repetitions for each subject was assessed in 15 subjects. Digital data was recorded by a Tablet PC using special software with average sampling rate of 120 Hz.Results: The quantified variables computed for circle and spiral drawing tests with preferred speed were reliable (0.55<ICC<0.85), so they can be used for drawing quantifications. Results of drawing circles with maximum speed were not reliable (ICC<0.5).Conclusion: repeatability analysis revealed that measures based on drawing circles with maximum speed are not repeatable and cannot be used for progress monitoring. This may be due to large variation in providing maximum drawing speed during test time. On the other hand, spiral and circle drawing parameters with preferred speed had a better repeatability and can be used for quantification of hand drawings in researches.

Background: Autonomic function assessment provides valuable information regarding the status of the autonomic nervous system. The time lag between the onset of orthostasis and the peak/nadir of heart rate response is a surrogate of the integrity of underlying autonomic neural pathways. Autonomic response latency (ARL) is a relatively novel yet underreported parameter in this context. Test-retest repeatability of this parameter has not been evaluated previously. Materials and Methods: We recruited 31 healthy adults (17 males and 14 females,29. 00 ± 5. 44 years) and subjected them to postural challenge tests on five instances – forenoon and afternoon of day 1, the next day, 1 week later, and 1 month later. Tachycardia and bradycardia latencies (TL and BL) were computed using heart rate derived from digital ECG data. repeatability was assessed using the intraclass correlation coefficient (ICC) and coefficient of variation (CoV). Results: ICCs for TL and BL were 0. 69 (0. 56, 0. 82) and 0. 77 (0. 66, 0. 87), respectively. The CoVs for TL and BL were 14. 8% and 12. 4%, respectively. Sex-based subgroup analysis revealed ICCs for TL and BL in males to be 0. 71 (0. 53, 0. 86) and 0. 74 (0. 57, 0. 88) and in females to be 0. 68 (0. 64, 0. 86) and 0. 82 (0. 66, 0. 93), respectively. CoVs for TL and BL were 14. 4% and 13. 8% in male subjects and 15. 4% and 10. 7% in female subjects, respectively. Conclusion: ARL to orthostatic challenge demonstrated moderate to good test-retest repeatability. Based on our observations, we propose that ARL has potential as a consistent and repeatable index for the assessment of the integrity of autonomic neural pathways and therefore can help in the diagnosis of autonomic neuropathy.

Introduction As functional magnetic resonance imaging (fMRI) is too expensive and time consuming, its frequent implementation is difficult. The aim of this study is to evaluate repeatability of detecting visual cortex activity in fMRI.Materials and Methods In this study, 15 normal volunteers (10 female, 5 male; Mean age±SD: 24.7±3.8 years) attended. Functional magnetic resonance images were obtained during a visual task of sine-wave with spatial frequency of 1.84 cpd and temporal frequency of 8 Hz in three scan runs. Two runs of functional images were provided consecutively in a session, and the third run was provided 1-6 weeks later. The activation map was created using the data obtained from the block-designed fMRI study. Voxels whose Z value was above a threshold of 2.3, at a significance level p=0.05, were considered activated. After image processing, the blood oxygen level dependent (BOLD) signal changes and the number of activated voxels in response to visual stimuli were compared in different runs.Results The results of this study demonstrate no significant difference between the number of activated voxels and BOLD signal in first and second runs in one session (Paired t-test, p>0.05). Moreover, there is a considerable correlation between first and second scan runs (rsignal=0.74, p=0.006 and rvoxel=0.62, p=0.03), while the correlation between the runs in separate sessions is weak (rsignal=0.28, p=0.38 and rvoxel=0.32, p=0.31).Conclusion Since the repeatability of BOLD signal and number of activated voxels in one session is considerably better than that in the separate sessions, it is suggested that in fMRI visual studies that need repeated scanning, scans should be acquired during a single session.

Purpose: To assess the repeatability of Pentacam AXL as a Scheimpflug-based system or measuring axial length according to the age, sex, lens type, axial length value, and type of cataract. Methods: The present study was conducted using multistage cluster sampling in Tehran, Iran. Ocular biometry was performed, using the Pentacam AXL, by an experienced optometrist on all the participants. The axial length (AL) measurements were taken thrice, with a gap of 10 minutes. To evaluate the repeatability, the intraclass correlation coefficient (ICC) and the repeatability coefficient (RC) were calculated. To determine the significant difference in the repeatability index among study variables, the tolerance index (TI) was calculated. Results: In this report, 897 eyes of 677 individuals aged between 20 and 91 years (mean ± SD: 64. 90 ± 13. 62 years) were reported. The ICC of the axial length measurements was 0. 981 for all cases. Based on the within-subject standard deviation, the RC was 0. 401. The ICC was 0. 976 and 0. 985 in men and women, respectively. The TI showed better RC of measurements among females. The ICC decreased from 0. 999 in participants under 40 years to 0. 973 in individuals over 60 years of age. The TI showed a decrease in RC with advancing age. The RC was worse in eyes with nuclear cataracts,the RC was also worse in the first quartile of the signal-to-noise ratio (SNR) compared to the other SNR quartiles. Conclusion: The Scheimpflug-based system Pentacam AXL had high repeatability in measuring axial length. Some variables such as male gender, older age, and nuclear cataract were associated with reduced repeatability of the measurements. A higher SNR was associated with better repeatability of the axial length measurements.