OBJECTIVES: The Korean Genome and Epidemiology Study (KoGES), a multicenter-based multi-cohort study, has collected information on body composition using two different bioelectrical impedence analysis (BIA) machines. The aim of the study was to evaluate the possibility of whether the test values measured from different BIA machines can be integrated through statistical adjustment algorithm under excellent inter-rater reliability. METHODS: We selected two centers to measure inter-rater reliability of the two BIA machines. We set up the two machines side by side and measured subjects' body compositions between October 2007 and December 2007. Duplicated test values of 848 subjects were collected. Pearson and intra-class correlation coefficients for inter-rater reliability were estimated using results from the two machines. To detect the feasibility for data integration, we constructed statistical compensation models using linear regression models with residual analysis and R-square values. RESULTS: All correlation coefficients indicated excellent reliability except mineral mass. However, models using only duplicated body composition values for data integration were not feasible due to relatively low R2 values of 0.8 for mineral mass and target weight. To integrate body composition data, models adjusted for four empirical variables that were age, sex, weight and height were most ideal (all R2>0.9). CONCLUSIONS: The test values measured with the two BIA machines in the KoGES have excellent reliability for the nine body composition values. Based on reliability, values can be integrated through algorithmic statistical adjustment using regression equations that includes age, sex, weight, and height.
Aged ; Biometry/*instrumentation/methods ; *Body Composition ; Cohort Studies ; Electric Impedance ; Female ; *Genome, Human ; Humans ; Male ; Middle Aged ; Observer Variation ; Reproducibility of Results ; Republic of Korea

PURPOSE: To compare the refractive results of cataract surgery measured by applanation ultrasound and the new partial coherence interferometer, AL-scan. METHODS: Medical records of 76 patients and 104 eyes who underwent cataract surgery from January 2013 to June 2013 were retrospectively reviewed. Biometries were measured using ultrasound and AL-scan and intraocular lens power was calculated using the SRK-T formula. Automatic refraction examination was done 1 month after the operation, and differences between the ultrasound group and AL-scan group were compared and analyzed by mean absolute error. RESULTS: Mean axial length measured preoperatively by the ultrasound method was 23.53 +/- 1.17 mm while the lengths measured using the AL-scan were 0.03 mm longer than that of the ultrasound group (23.56 +/- 1.15 mm). However, there was not a significant difference in this finding (p = 0.638). Mean absolute error was 0.34 +/- 0.27 diopters in the ultrasound group and 0.36 +/- 0.31 diopters in AL-scan group, which showed no significant difference (p = 0.946) in precision of predicting postoperative refraction. CONCLUSIONS: Although the difference was not statistically significant, intraocular lens calculations done by the AL-scan were nearly similar in predicting postoperative refraction compared to those of applanation ultrasound, however more precise measurements may be obtained if the axial length is longer than 24.4 mm. Except in the case of opacity in the media, which makes obtaining measurements with the AL-scan difficult, AL-scan could be a useful biometry in cataract surgery.
Aged ; Anterior Chamber/pathology ; Axial Length, Eye/*pathology ; Biometry/methods ; Female ; Humans ; Interferometry/*instrumentation ; *Lens Implantation, Intraocular ; Lenses, Intraocular ; Light ; Male ; Middle Aged ; *Phacoemulsification ; Refraction, Ocular/physiology ; Reproducibility of Results ; Retrospective Studies ; Visual Acuity/physiology