- MeSH
- Blood Pressure physiology MeSH
- Humans MeSH
- Blood Pressure Determination methods MeSH
- Reference Values MeSH
- Reproducibility of Results MeSH
- Check Tag
- Humans MeSH
- Publication type
- Comment MeSH
Cíl: Cílem studie je vyhodnotit opakovatelnost měření neinvazivního break-up time (NIBUT) keratografem při jeho stanovení z jednoho, dvou či třech dílčích měření a doporučit pro praxi vhodnou metodiku. Dalším cílem je ověřit, zda opakovaná měření neovlivňují měřenou hodnotu. Materiál a metodika: Do studie bylo zařazeno 38 zdravých dobrovolníků (30 žen a 8 mužů) ve věku od 19 do 50 let, u každého bylo měřeno vždy jen jedno oko. Studie byla koncipována jako prospektivní. Po 15minutové adaptaci na podmínky vyšetřovny podstoupil každý účastník dvě série měření NIBUT (test, retest) na keratografu OCULUS 3. Minimální časový odstup obou sérií byl 10 minut, každá série obsahovala tři dílčí měření v odstupu přibližně 3 minuty. Výsledný NIBUT byl v každé sérii stanoven (A) jako první hodnota v dané sérii, (B) jako průměr prvních dvou nebo (C) všech tří měření v dané sérii. Opakovatelnost byla hodnocena Bland-Altmanovou analýzou a vyjádřena koeficientem opakovatelnosti. Sledován byl vždy pouze čas prvního roztržení slzného filmu. Výsledky: Statistická analýza neprokázala statisticky signifikantní rozdíly jak mezi dílčími měřeními NIBUT v jednotlivých sérií (p = 0,92, p = 0,81), tak při porovnání všech šesti měření (p = 0,95). Průměrné hodnoty dílčích měření se pohybovaly od 13,6 s do 14,4 s. Pro postupy A, B a C byly zjištěny koeficienty opakovatelnosti (po řadě) 15,0 s, 12,1 s a 10,0 s. Doplňující analýza pro 12 očí s nízkým NIBUT (< 10 s) prokázala statisticky signifikantně lepší opakovatelnost v této skupině, a to s koeficienty 7,0 s (metodika A), 6,0 s (B) a 4,6 s (C) . Závěr: Stanovení NIBUT ze tří po sobě jdoucích měření (s dostatečným, ideálně několikaminutovým odstupem) významně zlepšuje opakovatelnost. Přitom takto opakovaná měření NIBUT nemají významný vliv na měřenou hodnotu. Uvedenou metodiku měření NIBUT na keratografu lze doporučit pro použití v praxi.
Aim: The primary aim of this study is to evaluate the repeatability of noninvasive break-up time (NIBUT) measurement by keratograph when it is determined from one, two or three partial measurements, and to recommend a suitable methodology for practice. Another goal is to verify that repeated measurements do not affect the measured value. Material and Methods: Thirty-eight healthy volunteers (30 women and 8 men) aged between 19 and 50 years old were included in the study, in which only one eye of each volunteer was measured. The study was designed as a prospective one. Each subject adapted to the local conditions of the laboratory for 15 minutes and subsequently underwent two series of NIBUT measurements (test, retest) on an OCULUS 3 Keratograph. The minimum time interval between the two series was 10 minutes, in which each series contained three partial measurements approximately 3 three measurements in the given series. Repeatability was assessed by a Bland-Altman analysis and expressed as a repeatability coefficient. In every case, only the time of the first break-up of the tear film was monitored. Results: The statistical analysis did not show statistically significant differences both between partial measurements of NIBUT in the individual series (p = 0.92, p = 0.81) and when comparing all six measurements (p = 0.95). The mean values of the partial measurements ranged from 13.6 s to 14.4 s. The repeatability coefficients were found to be 15.0 s, 12.1 s and 10.0 s for methodologies A, B and C, respectively. A supplementary analysis for 12 eyes with low NIBUT (< 10 s) showed statistically significantly better repeatability in this group, with coefficients of 7.0 s (methodology A), 6.0 s (B) and 4.6 s (C). Conclusion: Determination of NIBUT from three consecutive measurements (with a sufficient interval of ideally a few minutes) significantly improves repeatability. Such repeated NIBUT measurements do not have a significant effect on the measured value. The mentioned methodology for measuring NIBUT on a keratograph can be recommended for use in practice.
- Keywords
- slzný film, break-up time test, opakovatelnost měření, keratograf OCULUS 3,
- MeSH
- Diagnostic Techniques, Ophthalmological * classification instrumentation MeSH
- Prospective Studies MeSH
- Cornea diagnostic imaging physiology pathology MeSH
- Dry Eye Syndromes * diagnostic imaging diagnosis MeSH
- Publication type
- Research Support, Non-U.S. Gov't MeSH
Cíl: Cílem naší studie bylo prokázat statisticky významnou korelaci hodnot při opakovaném měření a statisticky významné rozdíly v opakovatelnosti, resp. spolehlivosti (test-retest variability, TRV) vyjádřenou tzv. intervalem shody (CI) podle metody Bland-Altmana na statisticky významné 95% hladině u různých metod testování zrakové ostrosti. Jedná se o metodu prahovou interpolační na optotypové tabuli ETDRS, celořádkovou metodu a modifikovanou prahovou interpolační metodu na optotypové tabuli Snellen v provedení se Sloanovými optotypovými znaky. Metodika: K dispozici jsme měli celkem 468 platných hodnot zrakové ostrosti naměřených prahovou interpolační metodou na ETDRS, celořádkovou metodou a prahovou interpolační metodou na optotypové tabuli Snellen. U celořádkové metody na optotypové tabuli Snellen byla průměrná hodnota zrakové ostrosti při prvním měření -0,043 logMAR (min. 1, max. -0,30, SD 0,25), při druhém měření -0,045 logMAR (min. 1, max. -0,30, SD 0,23). U metody prahové interpolační na optotypové tabuli Snellen byla zraková ostrost při prvním měření -0,018 logMAR (min. 0,98, max. -0,30, SD 0,29), při druhém měření -0,024 logMAR (min. 1, max. -0,80, SD 0,29). U metody prahové interpolační na optotypové tabuli ETDRS byla zraková ostrost při prvním měření -0,0612 logMAR (min. 0,72, max. -0,30, SD 0,21), při druhém měření -0,0610 log MAR (min. 0,8, max. -0,28, SD 0,21). Výsledky: Bylo prokázáno, že hodnoty zrakové ostrosti získané všemi třemi metodami se při opakovaném měření od sebe významně statisticky neliší (Wilcoxonův párový test, celořádková metodika Snellen p = 0,74, interpolační metodika Snellen p = 0,33 a interpolační metodika ETDRS p = 0,95) a na statisticky významné hladině spolu korelují (Spearmanův korelační koeficient, celořádková metodika Snellen r = 0,91, p < 0,0001, interpolační metodika Snellen r = 0,89, p < 0,0001 a interpolační metodika ETDRS r = 0,89, p < 0,0001). TRV vyjádřená dle metody Bland-Altmana tzv. limitem shody (confidence interval CI) na hladině 95% u opakovaných párových měření byla u metody celořádkové na optotypu Snellen ± 0,11 (tj. 5 znaků), u metody prahové interpolační na optotypu Snellen ± 0,20 (tj. 10 znaků) a u metody prahové interpolační na optotypu ETDRS ± 0,08 (tj. 4 znaky). Závěr: V naší studii jsme prokázali, že na statisticky významné hladině se od sebe neliší opakovaná měření u všech třech metod. Dále byla prokázána statisticky významná korelace mezi opakovaným měřením zrakové ostrosti u jednotlivých osob u všech třech metod. Klinicky nejvýznamnější je stanovení a potvrzení nejlepší opakovatelnosti u metody prahové interpolační na optotypu ETDRS (CI ± 0,08, tj. ± 4 znaky) v porovnání s metodou celořádkovou na optotypu Snellen (CI ± 0,11, tj. ± 5 znaků) a metodou interpolační na optotypu Snellen (CI ± 0,20, tj.± 10 znaků). Z našich měření vyplývá, že není klinicky přínosné převádět hodnoty zrakové ostrosti naměření na optotypu Snellen do logMAR a zohledňovat, dopočítávat (interpolovat) jednotlivé znaky u této metody.
Purpose: The main goal of our study was to prove the statistical significant correlation between repeated measurements and test-retest variability TRV expressed with confidence interval CI according to Bland-Altman's method on 95% level of statistical confidence. The methods are threshold interpolation log MAR method on ETDRS chart, whole-line method on Snellen chart and modified threshold interpolation method on Snellen chart with Sloan letters. Methods: We had 468 measurements measured with threshold interpolation log MAR method on ETDRS chart, whole-line method on Snellen chart and modified threshold interpolation method on Snellen chart with Sloan letters. The average value of the first sequence of measurements measured with whole-line method on Snellen chart was -0.043 logMAR (min. 1, max. -0.30. SD 0.25) and of the second sequence of measurements was - 0.045 logMAR (min. 1, max. -0.30. SD 0.23). The average value of the first sequence of measurements measured with interpolation method on Snellen chart was -0.018 logMAR (min. 0.98, max. -0.30. SD 0.29) and of the second sequence of measurements was -0.024 logMAR (min. 1, max. -0.80. SD 0.29). The average value of the first sequence of measurements measured with interpolation method on ETDRS chart was -0.0612 logMAR (min. 0.72, max. -0.30. SD 0.21) and of the second sequence of measurements was -0.0610 log MAR (min. 0.8, max. -0.28, SD 0.21). Results: We have proved that all methods do not have statistical significant difference between repeated measurements (Wilcoxon paired test, whole-line method on Snellen chart p = 0.74, interpolation method on Snellen chart p = 0.33 and interpolation method on ETDRS p = 0.95) and they also have statistical significant correlations (Spearman correlation coefficient, whole-line method on Snellen chart r = 0.91, p < 0.0001, interpolation method on Snellen chart r = 0.89, p < 0.0001 and interpolation method on ETDRS chart r = 0.89, p < 0.0001). TRV expressed with CI on 95% statistical significance level according to method of Bland-Altman was with whole-line method on Snellen chart ± 0.11 (i.e. 5 letters), with interpolation method on Snellen chart ± 0.20 (i.e. 10 letters) and with interpolation method on ETDRS ± 0.08 (i.e. 4 letters). Conclusion: In our study we proved that there is no statistical significant difference between repeated measurements with all three methods. After that we proved statistical significant correlations between repeated measurements with all three methods. The biggest clinical importance has determination and confirmation of the CI value of TRV. With interpolation method on ETDRS it was CI ± 0.08 (i.e. ± 4 letters), with whole-line method on Snellen it was CI ± 0.11 (i.e. ± 5 letters) and with interpolation method on Snellen it was CI ± 0.20 (i.e. ± 10 letters). Our recommendation based on results of our study is that is not clinically appropriate to convert measured values from Snellen optotype to logMAR and perform interpolation method on Snellen chart.
- Keywords
- prahová interpolační metoda, celořádková metoda, Sloanovy optotypové znaky, test-retest variabilita,
- MeSH
- Adult MeSH
- Humans MeSH
- Young Adult MeSH
- Reproducibility of Results MeSH
- Statistics as Topic MeSH
- Visual Acuity MeSH
- Vision Tests methods instrumentation statistics & numerical data MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Young Adult MeSH
- Male MeSH
- Female MeSH
- Publication type
- Evaluation Study MeSH
- Comparative Study MeSH
- MeSH
- Brachial Artery pathology MeSH
- Endothelium, Vascular pathology ultrasonography MeSH
- Adult MeSH
- Humans MeSH
- Reproducibility of Results MeSH
- Blood Flow Velocity physiology MeSH
- Ultrasonography methods MeSH
- Vasodilation physiology MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Publication type
- Comparative Study MeSH
OBJECTIVES: To describe the short- and medium-term repeatability of lung clearance index at 2.5% (LCI2.5 ) in infants and calculate the number of patients needed to enroll in a study (N) using LCI2.5 as a primary outcome. METHODS: An 8-month follow-up observational study was employed for assessing short-term [coefficient of repeatability (CR) and intraclass correlation (ICC)] and medium-term repeatability (Bland-Altman method) of LCI2.5 in infants with cystic fibrosis (CF) or recurrent wheeze (RW) measured by the nitrogen multiple-breath washout test (N2 -MBW). Using these variability data, the N to reach 90% test power at the level of statistical significance (0.05) was calculated. RESULTS: Forty infants with CF and 21 with RW were enrolled. Initial N2 -MBW testing was successful in 33 and 17 patients, respectively. Follow-up data were available for 23 and 11 infants, respectively. Short-term repeatability of LCI2.5 was high (CR = 1.10 and 1.04 in CF and RW patients, respectively; ICC = 0.88 and 0.83 in CF and RW patients, respectively). The between-subject standard deviation was <13% of the actual LCI2.5 value. In clinically stable patients, LCI2.5 did not significantly change during the 8-month follow-up. Mean LCI2.5 change was -0.08 (1% of baseline) in CF and -0.05 (0.6%) in RW, with 95% limits of agreement being (-1.70; 1.53) in CF and (-1.51; 1.40) in RW patients. N = 23 infants if both intragroup differences of LCI2.5 and minimal difference to be detected would be 2.0. CONCLUSION: N2 -MBW may be a reproducible tool with reasonable test power to detect differences in infant studies.
- MeSH
- Cystic Fibrosis * diagnosis MeSH
- Breath Tests methods MeSH
- Nitrogen MeSH
- Infant MeSH
- Humans MeSH
- Follow-Up Studies MeSH
- Lung MeSH
- Respiratory Function Tests methods MeSH
- Check Tag
- Infant MeSH
- Humans MeSH
- Publication type
- Journal Article MeSH
- Observational Study MeSH
- Research Support, Non-U.S. Gov't MeSH
Rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) is essential for proper initial antibiotic therapy and timely set up of hygienic measures. Recently, detection of MRSA using MALDI-TOF mass spectrometer mediated by the peptide-phenol-soluble modulin (PSM-mec)-linked to the class A mec gene complex present in SCCmec cassettes types II, III, and VIII of MRSA strains, has been commercially available. We present here a multicentre study on MALDI-TOF MS detection of MRSA evincing a poor repeatability and reproducibility of the assay. The sensitivity of the assay varies between 50 and 90% in strains carrying psmMEC and psmδ genes encoding for PSM-mec and δ-toxin (a member of the PSM peptide family), respectively. No false positive results were found. The very major error calculation was 30% and the major error achieved 0%. Interlaboratory repeatability varies between 0 and 100%. No significant difference was observed with the use of different cultivation media. Our data showed a poor sensitivity of the method excluding it from the use in routine laboratory testing.
- MeSH
- Bacterial Toxins genetics MeSH
- Diagnostic Errors MeSH
- Molecular Diagnostic Techniques * MeSH
- Diagnostic Tests, Routine MeSH
- Humans MeSH
- Methicillin-Resistant Staphylococcus aureus genetics isolation & purification MeSH
- Reproducibility of Results MeSH
- Sensitivity and Specificity MeSH
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization * MeSH
- Staphylococcal Infections diagnosis microbiology MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Multicenter Study MeSH
Locomotor activity is a major attribute of animals. Although this trait determines important ecological processes, such as dispersal and species interactions, the sources of its variation are not fully understood. We examined the influence of body temperature (13, 18, 23, and 28 °C) and individual identity on spontaneous locomotor activity in juvenile alpine newts, Ichthyosaura alpestris, over three consecutive weeks. Locomotor activity was characterized by four parameters: distance covered, mean velocity, frequency of movements, and total activity rate (all directional and non-directional movements). Apart from total activity rate, thermal reaction norms for locomotor parameters had convex or concave curvilinear shapes. During the first trial series, i.e. across the four body temperatures that were tested, individual identity explained less variation in thermal reaction norms than during the second series. Individual means, i.e. the vertical positions of individual thermal reaction norms, were repeatable between trial series in all locomotor activity parameters but the frequency of movements. We conclude that spontaneous locomotor activity is a complex trait, which can be characterized by several parameters with varying individual repeatability and thermal dependency. This information should be considered for planning further locomotor activity experiments, conservation strategies, and modeling ectotherm responses to climate change.
- MeSH
- Locomotion * MeSH
- Salamandridae physiology MeSH
- Body Temperature * MeSH
- Temperature MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
Predicting fish acute toxicity of chemicals in vitro is an attractive alternative method to the conventional approach using juvenile and adult fish. The rainbow trout (Oncorhynchus mykiss) cell line assay with RTgill-W1 cells has been designed for this purpose. It quantifies cell viability using fluorescent measurements for metabolic activity, cell- and lysosomal-membrane integrity on the same set of cells. Results from over 70 organic chemicals attest to the high predictive capacity of this test. We here report on the repeatability (intralaboratory variability) and reproducibility (interlaboratory variability) of the RTgill-W1 cell line assay in a round-robin study focusing on 6 test chemicals involving 6 laboratories from the industrial and academic sector. All participating laboratories were able to establish the assay according to preset quality criteria even though, apart from the lead laboratory, none had previously worked with the RTgill-W1 cell line. Concentration-response modeling, based on either nominal or geometric mean-derived measured concentrations, yielded effect concentrations (EC50) that spanned approximately 4 orders of magnitude over the chemical range, covering all fish acute toxicity categories. Coefficients of variation for intralaboratory and interlaboratory variability for the average of the 3 fluorescent cell viability measurements were 15.5% and 30.8%, respectively, which is comparable to other fish-derived, small-scale bioassays. This study therefore underlines the robustness of the RTgill-W1 cell line assay and its accurate performance when carried out by operators in different laboratory settings.
- MeSH
- Aniline Compounds toxicity MeSH
- Cell Line MeSH
- Laboratories MeSH
- Oncorhynchus mykiss MeSH
- Reproducibility of Results MeSH
- Toxicity Tests, Acute methods MeSH
- Cell Survival drug effects MeSH
- Dose-Response Relationship, Drug MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
PURPOSE: To assess the intraday repeatability of macular architecture measurements in glaucomatous and non-glaucomatous patients using spectral-domain optical coherence tomography (SD-OCT) and to evaluate the independence from intraindividual intraocular pressure (IOP) fluctuations. METHODS: In this single-center, time-point comparison study, 88 eyes with glaucoma, 53 eyes with ocular hypertension (OHT), and 253 healthy eyes underwent two standardized SD-OCT and intraocular pressure (IOP) measurements on the same day with a 5-h time gap. Bland-Altman plots, intraclass correlation coefficients (ICC), and random-effects model were used to analyze repeatability of entire retinal thickness, retinal nerve fiber layer, ganglion cell layer, inner plexiform layer, and inner nuclear layer measurements. RESULTS: Intraday measurements were highly reproducible in all 3 groups. ICC were greater than 0.90, respectively. The pairwise comparisons of morphometric parameters showed a statistically significant difference (P < 0.001, respectively) between groups (glaucoma vs. control, glaucoma vs. OHT) and a significant influence of time points. No correlation was found between IOP fluctuations and morphometric parameters (P > 0.05, respectively), except for a weak positive correlation with GCL (rho = 0.109, P = 0.031). CONCLUSIONS: The evaluation of macular morphometric parameters of SD-OCT showed a high intraday repeatability and an excellent degree of agreement in glaucoma, ocular hypertension, and healthy groups. The fixed effects of time points were statistically significant. Except for a weak positive correlation of ganglion cell layer, variability did not appear to be affected by intraday IOP changes. Additional research is required to fully understand the impact of IOP fluctuations on macular morphometric parameters, considering the small observed IOP changes.
- MeSH
- Adult MeSH
- Glaucoma * diagnosis physiopathology MeSH
- Middle Aged MeSH
- Humans MeSH
- Macula Lutea * pathology diagnostic imaging MeSH
- Follow-Up Studies MeSH
- Nerve Fibers * pathology MeSH
- Intraocular Pressure * physiology MeSH
- Ocular Hypertension diagnosis physiopathology MeSH
- Tomography, Optical Coherence * methods MeSH
- Reproducibility of Results MeSH
- Retinal Ganglion Cells * pathology MeSH
- Aged MeSH
- Tonometry, Ocular MeSH
- Visual Fields physiology MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Comparative Study MeSH