scholarly journals Methacholine Challenges: comparison of different tidal breathing challenge methods

2021 ◽  
pp. 00282-2021
Author(s):  
James Dean ◽  
Natalie Jackson ◽  
Brett Keidel-Morgan ◽  
Daniel Hamer ◽  
Dave Singh
Keyword(s):  
Correlation Coefficient ◽  
Intraclass Correlation ◽  
Methacholine Challenge ◽  
Tidal Breathing ◽  
Continuous Output ◽  
Asthma Patients ◽  
Output Time ◽  
Good Repeatability ◽  
The Mean ◽  
Dose Step

Tidal breathing methacholine challenges are now recommended by guidelines, to avoid the bronchoprotective effects of deep inhalation. This study compared different tidal breathing methacholine challenge methods, assessed the agreement between tidal dosimetric and continuous output challenges, and challenge repeatability with different methods. 15 asthma patients performed dosimetric challenges and a continuous output breath actuated challenge, all at least 3 days apart. All subjects had a pre-bronchodilator forced expired volume in 1 s (FEV1) ≥65% predicted, and PD20 <1.2 mg. Of the dosimetric challenges, one method increased methacholine concentration (standard dosimetric challenge), and one adjusted nebuliser output time to increase dose (adjusted dosimetric challenge). The adjusted dosimetric and continuous output challenges were performed twice on separate days to assess for repeatability. All challenges were matched for dose at each dose step. The mean PD20 ratio of the standard dosimetric challenge to the adjusted dosimetric challenge was 0.90 (CI: 0.66–1.23; p=0.49), and intraclass correlation coefficient (ICC)=0.82. Repeated adjusted dosimetric challenges had an ICC=0.62 for PD20. Repeated continuous output challenges had an ICC =0.74 for PD20. The adjusted dosimetric and continuous output challenges correlated (r=0.69, p=0.0043; ICC: 0.65), but PD20 was higher for the adjusted dosimetric challenge (mean PD20 ratio=2.31; CI: 1.57–3.40; p=0.0004). Tidal dosimetric methacholine challenge using adjustment of nebuliser output produces results with good repeatability. The results of this adjusted dosimetric method differed from the continuous output method, underscoring that the results of different methacholine challenge methodologies may not be directly comparable.

scholarly journals A Quantitative Comparison of Multispectral Refraction Topography and Autorefractometer in Young Adults

2021 ◽  
Vol 8 ◽  
Author(s):  
Yunru Liao ◽  
Zhenlan Yang ◽  
Zijing Li ◽  
Rui Zeng ◽  
Jing Wang ◽  
...  
Keyword(s):  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
High Agreement ◽  
Intraclass Correlation Coefficients ◽  
Repeatability And Reproducibility ◽  
The Mean

Purpose: Purpose of this study is to evaluate the measuring consistency of central refraction between multispectral refraction topography (MRT) and autorefractometry.Methods: This was a descriptive cross-sectional study including subjects in Sun Yat-sen Memorial Hospital from September 1, 2020, to December 31, 2020, ages 20 to 35 years with a best corrected visual acuity of 20/20 or better. All patients underwent cycloplegia, and the refractive status was estimated with autorefractometer, experienced optometrist and MRT. We analyzed the central refraction of the autorefractometer and MRT. The repeatability and reproducibility of values measured using both devices were evaluated using intraclass correlation coefficients (ICCs).Results: A total of 145 subjects ages 20 to 35 (290 eyes) were enrolled. The mean central refraction of the autorefractometer was −4.69 ± 2.64 diopters (D) (range −9.50 to +4.75 D), while the mean central refraction of MRT was −4.49 ± 2.61 diopters (D) (range −8.79 to +5.02 D). Pearson correlation analysis revealed a high correlation between the two devices. The intraclass correlation coefficient (ICC) also showed high agreement. The intrarater and interrater ICC values of central refraction were more than 0.90 in both devices and conditions. At the same time, the mean central refraction of experienced optometrist was −4.74 ± 2.66 diopters (D) (range −9.50 to +4.75D). The intra-class correlation coefficient of central refraction measured by MRT and subjective refraction was 0.939.Conclusions: Results revealed that autorefractometry, experienced optometrist and MRT show high agreement in measuring central refraction. MRT could provide a potential objective method to assess peripheral refraction.

scholarly journals Establishing the reference value for tibial tubercle-trochlear groove distance on MRI in Southern Chinese population and its correlation with age, sex, height, weight and size: A multi-centre study

2020 ◽  
pp. 221049172096970
Author(s):  
Kwun Man Cyrus Mo ◽  
Kwan Yin Francis Cho ◽  
Ka Yan Alice Au ◽  
Ka Yin Gregory Lee ◽  
Hei Man Joyce Cheng
Keyword(s):  
Correlation Coefficient ◽  
Chinese Population ◽  
Intraclass Correlation ◽  
Tibial Tubercle ◽  
P Value ◽  
Trochlear Groove ◽  
Measurement Reliability ◽  
Multi Centre Study ◽  
Southern Chinese ◽  
The Mean

Objective: The first objective of this study is to determine the reference Tibial Tubercle-Trochlear Groove (TT-TG) distance on MRI in Southern Chinese population. The second objective is to investigate the correlation between TT-TG distance and (i) age, (ii) sex, (iii) height, (iv) weight and (v) Body Mass Index (BMI) respectively. Method: Three hundred MRI knees performed in two different centres between August 2017 and October 2018 were included. All patients were prospectively recruited after MRI referral from Orthopaedics department. The TT-TG distances were measured by two radiologists independently. Measurement reliability was assessed using intraclass correlation coefficient (ICC). One sample t-test was used to compare the results between this study and other published studies. Spearman’s rank correlation coefficient was used to determine correlations between the TT-TG distance and age, sex, height, weight and BMI respectively. Result: There was no statistical significance between the mean of TT-TG distances from the two radiologists ( P-value = 0.32). The measurement reliability was excellent (ICC = 0.922 ± 0.02). The mean of averaged TT-TG distance was 8.32 ± 0.33 mm (range 2.01 to 17.48 mm). There were no statistical significant differences in means of TT-TG distance between laterality and gender. There were statistically significant correlations between (i) TT-TG distance and age ( p-value = 0.009), and (ii) TT-TG distance and height ( p-value = 0.014). Conclusion: The reference TT-TG distance on MRI in Southern Chinese population was 8.32 ± 0.33 mm. Statistically significant correlations were established between (i) TT-TG distance and age; and (ii) TT-TG distance and height.

scholarly journals Reliability Measurement of Corneal Wavefront Aberrations using Corneal Videokeratograph Atlas 9000

2020 ◽  
Vol 18 (2) ◽  
Author(s):  
Noorshazana Mat Rejab @ Md Rejab ◽  
Mohd Radzi Hilmi ◽  
Khairidzan Mohd Kamal ◽  
Md Muziman Syah Md Mustafa
Keyword(s):  
Correlation Coefficient ◽  
Intraclass Correlation Coefficient ◽  
Spherical Aberration ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Time Interval ◽  
Wavefront Aberration ◽  
Wavefront Aberrations ◽  
The Mean ◽  
Reliability Measurement

Introduction: Accurate corneal wavefront aberration measurements are essential in determining patient’s suitability, vision outcomes and patient satisfaction in laser refractive surgeries. This study aimed to evaluate the reliability measurement of higher-order aberration (HOA) using corneal videokeratograph Atlas 9000. Materials and method:  38 eyes of 19 participants were recruited in this study. Comprehensive eye examination was done to ensure all participants eligibility, and any conditions in which obstruct the central cornea were excluded. Corneal wavefront aberrations were measured based on Zernike polynomials. In assessing repeatability, three repetitive measurements in five minutes in a single session were taken by 2 experience examiners. For reproducibility measurement, similar approach was done with the time-interval between measurements was set at one week. Bland-Altman, limits of agreement (LoA) and intraclass correlation coefficients (ICCs) were used to evaluate the reliability measurement. Results: Bland-Altman and LoA findings revealed no significant differences for both repeatability and reproducibility measurement. For repeatability testing, the mean differences for vertical trefoil, oblique trefoil and spherical aberration were -0.096 ± 0.493, 0.001 ± 0.048, 0.008 ± 0.035, 0.004 ± 0.029, 0.010 ± 0.053 with LoA of 1.930, 0.188, 0.138, 0.114, and 0.208 respectively. Intraclass correlation coefficient (ICC) excellent reliability of 0.841 for all parameters. Likewise, reproducibility  testing showed similar findings  with the mean difference were -0.018 ± 0.091, 0.016 ± 0.061, -0.0004 ± 0.036, -0.002 ± 0.042, 0.003 ± 0.026, with LoA of 0.356, 0.24, 0.141,0.164, and 0.102 respectively. Intraclass correlation coefficient (ICC) shows excellent reliability of more than 0.9 for all parameters. LoA of less than 1.0 were observed in all measurements (except for repeatability of vertical trefoil) indicates high consistency of the measurements. Conclusions: Corneal videokeratograph Atlas 9000 provides excellent HOA measurement reliability.

Validity and reliability of Korean version of simplified nutritional appetite questionnaire in patients with advanced cancer: A multicenter, longitudinal study.

2017 ◽  
Vol 35 (31_suppl) ◽  
pp. 211-211
Author(s):  
Su-Jin Koh ◽  
So Yeon Oh ◽  
Ji Yeon Baek ◽  
Kyung A. Kwon ◽  
Hei-Cheul Jeung ◽  
...  
Keyword(s):  
Weight Loss ◽  
Cancer Patients ◽  
Correlation Coefficient ◽  
Advanced Cancer ◽  
Screening Tool ◽  
Intraclass Correlation ◽  
Validity And Reliability ◽  
Advanced Cancer Patients ◽  
Korean Version ◽  
The Mean

211 Background: Malnutrition and a loss of muscle mass are frequent in cancer patients and have a negative effect on clinical outcome. Nutrition risk screening aims to increase awareness and allow early recognition and treatment of cancer cachexia. Therefore, screenings should be brief, inexpensive, highly sensitive, and have good specificity. SNAQ is a simple screening tool including 4 questions, and validated to predict weight loss within 6 months in community-dwelling adults and nursing home residents. Our study aimed to translate the SNAQ into Korean, and to assess the validity and reliability of the translated screening tool in advanced cancer patients. Methods: The SNAQ was translated into Korean according to linguistic validation. The internal consistency of the SNAQ was evaluated by Cronbach’s alpha coefficient. Test–retest reliability was evaluated using the intraclass correlation coefficient. Concurrent validity was evaluated by measuring the Pearson’s correlation coefficient between the SNAQ and Mini-Nutritional Assessment (MNA) and Patient-Generated Subjective Global Assessment (PG-SGA). Results: In the 194 patients included in full analysis set, cancer stage was predominantly (98.5%) metastatic, the mean age was 60 years, and the mean BMI was 24 kg/m2. According to MNA score ≤11, 57 patients (29.3%) were malnourished. The mean score of the Korean version of the SNAQ was 13.8 (SD = 2.5) with a range of 6–19. Cronbach’s alpha coefficient was 0.74, and intraclass correlation coefficient was 0.87. The SNAQ was moderately correlated with MNA(r = 0.4043, p < 0.0001) and PG-SGA(r = -0.5297, p < 0.0001). A significant weight loss of 5% of the original body weight within 6 months occurred in 46 (24.7%) of the 186 patients. SNAQ score ≤14 predicted 5% weight loss with a sensitivity of 56.5% and a specificity of 44.3%. Conclusions: The Korean version of the SNAQ had high validity and reliability. SNAQ is useful for the screening tool for advanced cancer patients. The SNAQ had a limitation to predict impending weight loss in advanced cancer patients.

scholarly journals Individuality of the plasma sodium concentration

2014 ◽  
Vol 306 (12) ◽  
pp. F1534-F1543 ◽  
Author(s):  
Zheng Zhang ◽  
Jonathan Duckart ◽  
Christopher G. Slatore ◽  
Yi Fu ◽  
Amanda F. Petrik ◽  
...  
Keyword(s):  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Intraclass Correlation ◽  
Sodium Concentration ◽  
Patient Specific ◽  
Plasma Sodium ◽  
Set Point ◽  
Plasma Sodium Concentration ◽  
Specific Factors ◽  
The Mean

Older literature has suggested that the plasma sodium concentration is not individual, that it is neither intrinsic to an individual nor reproducible, longitudinally. We recently observed that the plasma sodium concentration is heritable. Because demonstrable heritability requires individuality of the relevant phenotype, we hypothesized that the plasma sodium concentration was substantially individual. In two large health plan-based cohorts, we demonstrated individuality of the plasma sodium concentration over a 10-yr interval; the intraclass correlation coefficient (ICC) averaged 0.4–0.5. The individuality of plasma sodium increased significantly with age. Plasma sodium individuality was equal to or only slightly less than that for plasma glucose but was less than the individuality for creatinine. The individuality of plasma sodium was further confirmed by comparing the Pearson correlation coefficient for within-individual versus between-individual pairs of sodium determinations and via application of the agreement index. Furthermore, the distribution of all sodium determinations for all participants within a population was similar to the distribution for the mean sodium concentration for individuals within that population. Therefore, the near-normal distribution of plasma sodium measurements within a population is likely not attributable to assay-specific factors but rather to genuine and durable biological variability in the osmotic set point. In aggregate, these data strongly support the individuality of the plasma sodium concentration. They further indicate that serial plasma sodium values for any given individual tend to cluster around a patient-specific set point and that these set points vary among individuals.

Repeatability and reproducibility of corneal biomechanical parameters derived from Corvis ST

2019 ◽  
Vol 30 (6) ◽  
pp. 1287-1294
Author(s):  
Nermin Serbecic ◽  
Sven Beutelspacher ◽  
Lovro Markovic ◽  
Abhijit Sina Roy ◽  
Rohit Shetty
Keyword(s):  
Correlation Coefficient ◽  
Intraclass Correlation Coefficient ◽  
Coefficient Of Variation ◽  
Intraclass Correlation ◽  
Diurnal Changes ◽  
Good Reliability ◽  
Good Repeatability ◽  
Repeatability And Reproducibility ◽  
Biomechanical Parameters ◽  
High Intraclass Correlation Coefficient

Introduction: The aim of this study was to evaluate repeatability and reproducibility of newly calculated biomechanical parameters of the cornea, developed by our research group. Methods: One eye from each of the 23 healthy subjects was measured three times consecutively, three times at different daytimes and on three different days. The within-subject standard deviation and coefficient of variation, as well as the intraclass correlation coefficient, were calculated for every parameter in each group. Results: Excellent repeatability and reproducibility (coefficient of variation < 5%, intraclass correlation coefficient > 0.75) was found for corrected values measured at A1, HC, and A2 time points (2nd A2 Time, 2nd A1 Time, 2nd HC Time, 2nd HC Def Amp and 2nd A1 Def Amp). Corneal-specific stiffness parameters, which showed good repeatability and reliability, were DA_cor (coefficient of variation = 4.02%, intraclass correlation coefficient = 0.919), KcLinear (coefficient of variation = 4.03%, intraclass correlation coefficient = 0.895), areaForceCornea (coefficient of variation = 3.34%, intraclass correlation coefficient = 0.853) and E2 (coefficient of variation = 4.1%, intraclass correlation coefficient = 0.78). Overall, most parameters fell into the category of good reliability (high intraclass correlation coefficient) and poor reproducibility (low coefficient of variation), including all the parameters describing extraocular deformation (DA_ext, AEPvED, AUC EDef, areaForceExtra, Kg and μg). Comparing the coefficient of variation values for intrasession, intersession and daytime measurements, there were no indices for diurnal changes. Conclusion: Most parameters showed good repeatability and reliability. The extraocular stiffness parameters showed poor reproducibility. KcLinear can serve as a very reliable and repeatable indicator of corneal stiffness.

scholarly journals The Reproducibility of the Jaw Index in the Measurement of Healthy Newborns

2019 ◽  
Vol 57 (5) ◽  
pp. 574-580
Author(s):  
J.F. Mermans ◽  
S.M. Ghasemi ◽  
B.I. Lissenberg-Witte ◽  
J.P.W. Don Griot
Keyword(s):  
Correlation Coefficient ◽  
Average Length ◽  
Intraclass Correlation ◽  
Feeding Problems ◽  
Interclass Correlation Coefficient ◽  
Interclass Correlation ◽  
The Mean ◽  
Maxilla And Mandible ◽  
Measuring Tool ◽  
The Relationship

Objective: Establish the reliability of the jaw index to objectify the relationship between the maxilla and mandible in healthy newborns. Design: Cohort study. Setting: Tertiary setting. Patients: A total of 52 healthy newborns were included to detect an inter and intraclass correlation coefficient (ICC) of 0.8 with a 95% confidence interval (95% CI) of width 0.3. Inclusion criteria were children born full term without respiratory or feeding problems, and without congenital malformations or facial deformities due to birth trauma. Uncooperative patients were excluded. Interventions: The jaw index, a measuring tool for objectifying micrognathia in children suspected of having Robin sequence, was used. An ICC of greater than 0.8 was considered clinically relevant. Main Outcome Measure(s): Primary outcomes are the reliability of the jaw index expressed as interclass correlation coefficient and ICC. Secondary outcomes are the mean jaw index and mean length of the mandible, maxilla, and the alveolar overjet. Results: An interclass correlation coefficient of 0.74 (95% CI: 0.49-0.86) and an ICC of 0.81 (95% CI: 0.66-0.89) were found. The mandible had an average length of 162.6 mm (standard deviation [SD] 11.1), the maxilla 168.7 mm (SD 9.4), the alveolar overjet 2.0 mm (SD 0.60), and the mean jaw index was 2.1 (SD 0.64). Conclusion: The jaw index is a consistent instrument between different observers as well as for one observer measuring consecutively in the same child, to objectify the size of the lower jaw compared to that of the upper jaw in healthy newborns.

scholarly journals The Axis-patella Index: A New Method for Measuring Patellar Height

2020 ◽  
Author(s):  
Hua Han ◽  
Xiaohui Zhang
Keyword(s):  
Correlation Coefficient ◽  
Reference Range ◽  
Articular Surface ◽  
Intraclass Correlation ◽  
Patellar Height ◽  
New Method ◽  
Strongly Correlated ◽  
Accurate Identification ◽  
Adjacent Structures ◽  
The Mean

Abstract Background: The widely used methods for measuring patellar height are based on the anatomic landmarks of the patella and the proximal tibia. When the knee undergoes alterations in the articular surface or adjacent structures due to various diseases or operations, the accurate identification of tibial landmarks is challenging. The results of these conventional methods may be biased or even unavailable. The purpose of this study was to introduce and validate a new method, axis-patella index (API), for assessing patellar height. Methods: Patellar heights were respectively measured using the Insall–Salvati, modified Insall–Salvati, Blackburne–Peel, Caton–Deschamps, plateau-patellar angle, and axis-patella methods on the lateral radiographs of 649 knees without anatomic abnormalities. The inter- and intra-observer reliability of all methods were evaluated by calculating intraclass correlation coefficient and Bland-Altman plots. The associations between the API and the established methods were assessed using Pearson’s correlation coefficient. Results: The API was strongly correlated with the five aforementioned methods. Reliability analyses indicated high inter-observer reproducibility and intra-observer repeatability. The mean of API was approximately 1.5, hence the reference range was defined 1.2 - 1.9 according to the 95% confidence interval. Conclusions: The API, a new index of referencing the tibial shaft axis and the fibular head, providing a valid and accurate alternative for the assessment of patellar height. The reference range was 1.2 - 1.9 in radiographically normal knee.

scholarly journals Precision of Corneal Thickness Measurements Obtained Using the Scheimpflug-Placido Imaging and Agreement with Ultrasound Pachymetry

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Jinhai Huang ◽  
Giacomo Savini ◽  
Chengfang Wang ◽  
Weicong Lu ◽  
Rongrong Gao ◽  
...  
Keyword(s):  
Healthy Subjects ◽  
Corneal Thickness ◽  
Intraclass Correlation ◽  
Normal Subjects ◽  
Limits Of Agreement ◽  
Ultrasound Pachymetry ◽  
Good Repeatability ◽  
Repeatability And Reproducibility ◽  
The Mean ◽  
Thickness Measurements

Purpose.To assess the reliability and comparability of measuring central corneal thickness (CCT) and thinnest corneal thickness (TCT) using a new Scheimpflug-Placido analyzer (TMS-5, Japan) and ultrasound (US) pachymetry.Methods.Seventy-six healthy subjects were prospectively measured 3 times by 1 operator using the TMS-5, 3 additional consecutive scans were performed by a second operator, and ultrasound (US) pachymetry measurements were taken. The test-retest repeatability (TRT), coefficient of variation (CoV), and intraclass correlation coefficient (ICC) were calculated to evaluate intraoperator repeatability and interoperator reproducibility. Agreement among the devices was assessed using Bland-Altman plots and 95% limits of agreement (LoA).Results.The intraoperators TRT and CoV were <19 μm and 2.0%, respectively. The interoperators TRT and CoV were <12 μm and 1.0%, respectively, and ICC was >0.90. The mean CCT and TCT measurements using the TMS-5 were 15.97 μm (95% LoA from −26.42 to −5.52 μm) and 20.32 μm (95% LoA from −30.67 to −9.97 μm) smaller, respectively, than those using US pachymetry.Conclusions.The TMS-5 shows good repeatability and reproducibility for measuring CCT and TCT in normal subjects but only moderate agreement with US pachymetry results. Caution is warranted before using these techniques interchangeably.

scholarly journals Comparison of Anterior Segment Measurements Obtained by Three Different Devices in Healthy Eyes

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Carmen Lopez de la Fuente ◽  
Ana Sanchez-Cano ◽  
Francisco Segura ◽  
Isabel Pinilla
Keyword(s):  
Healthy Volunteers ◽  
Correlation Coefficient ◽  
Intraclass Correlation Coefficient ◽  
Normal Values ◽  
Intraclass Correlation ◽  
Anterior Segment ◽  
Repeated Measurements ◽  
The Other ◽  
Good Repeatability ◽  
Healthy Eyes

Purpose. To assess the normal values and the repeatability of the Galilei Dual Scheimpflug Analyzer (GDSA), the biometer IOL Master, and the autokerato/refractometer WAM 5500 in anterior segment examinations.Methods. Eighty-eight eyes from 88 healthy volunteers were prospectively and consecutively recruited. The repeatability was assessed, calculating the intraclass correlation coefficient (ICC).Results. The correlations among the repeated measurements showed nearly perfect reliability (ICC > 0.81) for all of the parameters, except corneal astigmatism Galilei (0.79) and WAM (0.68). There were statistically significant differences (P<0.001) between the values of the flat simulated keratometry (SimK) and the steep SimK measured by GDSA and the other methods; however, there were no statistically significant differences for the values obtained with the IOL Master and WAM 5500 (P=0.302andP=0.172, resp.) or between the values of the ACD (P<0.001) and WTW (P=0.007) measured by the IOL Master and GDSA.Conclusions. The anterior segment measurements from the IOL Master and WAM 5500 were highly repeatable, comparable, and well correlated. In healthy young persons, the evaluated parameters had very good repeatability, although significant differences were found between the GDSA and IOL Master and between the GDSA and WAM 5500.

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