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PURPOSE: This study aimed to evaluate the consistency of preoperative keratometric values, anterior segment, and intraocular lens (IOL) power measurements in patients with cataract and no comorbidities using the Sirius topography device (CSO, Italy) and Lenstar LS 900 (Haag-Streit AG, Köeniz, Switzerland). METHODS: Patients with grade 2 and 3 cataracts who applied to Ophthalmology Clinic of Diskapi Yildirim Beyazit Education and Research Hospital, University of Health Sciences and planned for cataract surgery were included the study. Forty eyes with cataract from 40 patients were taken in the study. All patients underwent preoperative assessment using a combined Scheimpflug-Placido disc-based tomography device (Sirius) and Lenstar before cataract surgery. Keratometric measurements, such as flat keratometry (K1), steep keratometry (K2), and maximum keratometry (Kmax), and anterior segment parameters, white-to-white (WTW) distance, IOL power, astigmatism (AST), anterior chamber depth (ACD), aqueous depth (AD), and central cornea thickness (CCT), were recorded. RESULTS: There were significant differences between K1Lenstar and K1Sirius, K2Lenstar and K2Sirius, KmaxLenstar and KmaxSirius, WTWLenstar and WTWSirius, and IOL powerLenstar versus IOL powerSirius. However, there were insignificant differences between ASTLenstar and ASTSirius, ACDLenstar versus ACDSirius, ADLenstar and ADSirius, and CCTLenstar and CCTSirius variables. Furthermore, it was found that Sirius measured significantly higher than Lenstar, especially in terms of IOL power. CONCLUSION: Significant differences were observed between Lenstar and Sirius in terms of keratometric values, WTW distance, and IOL power. The IOL power value measured with Sirius was found to be higher than the IOL power value measured with Lenstar.

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Some adjustments are made to design weights to reduce the negative effects of non-response and out-of-scope problems. The calibration approach is a weighting process that agrees with the known population values by using auxiliary information. In this study, alternative calibration approaches and weight trimming process that can be used in large data sets with extreme weights and different correlation structures were analysed. In addition, the effect of the correlation structure of auxiliary variables on the efficiency of the calibration estimators was investigated by a simulation study. The 2017 Annual Industry and Service Statistics data were used in the simulation study and it was seen that restricted calibration estimators were more efficient than the generalized regression estimator in estimating the variables with a high variance such as turnover. Especially in small sample fractions, we recommend the application of restricted calibration estimators, as they are more efficient than the weight trimming in solving the negative and less than one weights problem encountered after the calibration process.

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In this study, some shrinkage estimators using a median ranked set sample in the presence of multicollinearity were studied. Initially, we constructed the multiple regression model using median ranked set sampling. We also adapted the Ridge and Liu-type estimators to these multiple regression model. To investigate the efficiency of these estimators, a simulation study was performed for a different number of explanatory variables, sample sizes, correlation coefficients, and error variances in perfect and imperfect ranking cases. In addition, these estimators were compared with other estimators that are based on ranked set sample using simulation study. It is shown that when the collinearity is moderate, Ridge estimator using median ranked set sample performs better than other estimators and when the collinearity increases, Liu-type estimator using median ranked set sample gets better than all other estimators do. When the collinearity is smaller than 0.95, ridge estimator based on median ranked set sample is more efficient than Liu-type estimator based on same sample. However, this threshold increases as the sample size increases and the number of explanatory variables decreases. In addition, real data example is presented to illustrate how collinearity affects the estimators under median ranked set sampling and ranked set sampling.

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BACKGROUND: Hallux valgus (HV) is one of the most common deformities of the foot, and it causes great difficulties for the patients. OBJECTIVE: We aimed to investigate the effects of different rigid taping techniques on HV angle, foot motor performance, balance and walking parameters. METHODS: Twenty-two voluntary individuals (12 males, 10 females) with flexible HV deformities between 18 and 35 years of age were included in the study. All measurements were done before and after placebo, athletic and Mulligan tapings were applied. After a three-day interval, new taping was applied on the same subject. HV angle was measured by goniometer. Foot motor performance (single leg heel rise test), balance (unilateral stance, limits of stability, sensory integration of balance) and temporospatial parameters of gait (step length, stride length, step width, foot angle and cadence) were evaluated. RESULTS: HV angles were reduced in all taping groups (p< 0.05). The Mulligan taping method was the most effective method in reducing HV angle. Foot motor performance was not affected by any type of taping (p> 0.05). Athletic taping increased step length and step width but reduced foot angle and cadence. The Mulligan taping increased cadence and reduced foot angle (p< 0.01). Both taping methods did not affect the postural stability and fall risk (p> 0.05). Stability limits were increased in Mulligan taping group (p< 0.05). CONCLUSION: It can be concluded that Mulligan taping method may be an alternative treatment method for HV rehabilitation especially as it increased the limits of stability and maintaining the balance. Mulligan method is more effective than athletic taping in terms of reducing instant HV angle.

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PURPOSE: To compare the retinal toxicity due to hydroxychloroquine (HCQ) use in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) using multifocal electroretinography (mfERG), fundus autofluorescence (FAF) and optical coherence tomography (OCT). METHODS: Patients who were using HCQ due to SLE and RA, and healthy subjects evaluated in this study. Central foveal thickness (CFT), inner-outer segment (IS-OS) junction irregularity, retinal nerve fiber layer thickness, mfERG and FAF measurements were performed to evaluate retinal toxicity. RESULTS: Study included 35 eyes of 35 SLE patients, 40 eyes of 40 RA patients and 20 eyes of 20 healthy subjects. In SLE group, retinal abnormality was found in three eyes with mfERG, in one eye with FAF and in four eyes with OCT. In RA group, retinal abnormality was found in 10 eyes with mfERG, in five eyes with FAF and in nine eyes with OCT. A statistically significant difference was found with respect to mfERG between "eyes with abnormal responses and without abnormal responses" and "eyes with abnormal responses and controls" (p < 0.05). A statistically significant difference was found with respect to CFT between "eyes with IS-OS junction irregularities and without IS-OS junction irregularities" and "eyes with/without IS-OS junction irregularities and controls" (p < 0.05). CONCLUSIONS: The use of HCQ seems to cause retinal toxicity more often in RA patients compared to SLE patients. For the early detection of retinal changes, OCT and mfERG can be used as screening tools due to their higher sensitivity rates compared to other tests.

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