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Results for “Reproducibility”

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PubMed1996

Reproducibility of 24-h energy expenditure and macronutrient oxidation rates in an indirect calorimeter.

The maintenance of weight and adipose tissue mass in humans appears to be related to a balance between the rates of oxidation and consumption of macronutrients; yet, little evidence is available on the reproducibility of 24-h macronutrient oxidation rates and how this relates to diet in the days preceding a chamber session. This study examined the reproducibility of 24-h macronutrient oxidation rates, 24-h energy expenditure (EE), and respiratory quotient (RQ) in 30 adults who ate their habitual diets before two 24-h whole body indirect calorimeter sessions. Results showed that the within-subject coefficients of variation (CVws) for 24-h EE and RQ were 2.8 and 2.6%, respectively. CVws for macronutrient oxidations ranged from approximately 15 to 25%. Means comparisons of 24-h EE, RQ, and macronutrient oxidation rates between sessions showed no significant differences, and all variables had significant positive intraclass correlation coefficients (P < 0.05). In conclusion, macronutrient oxidations all showed significant reproducibility for the group and a significant but lower reproducibility for individuals when habitual diet and activity preceded the experimental sessions.

Adipose Tissue↗

PubMed1998

Surface-specific electrical occlusal caries diagnosis: reproducibility, correlation with histological lesion depth, and tooth type dependence.

Electrical conductance measurements are being used experimentally for occlusal caries detection. Recently, it was suggested to cover the fissure system with a conducting medium, resulting in a surface-specific measurement. It was the aim of this study to determine in vitro the reproducibility of this modified technique for occlusal caries in posterior teeth, to determine for a large study sample the correlation between the electrical measurements and histological lesion depth, and to evaluate the difference between results for premolars and molars. For the reproducibility determination, surface-specific electrical resistance measurements were made using a sample of 68 posterior teeth. Eight operators performed measurements on all teeth, and repeated measurements on 24 teeth. The validity study included the previous sample and the collected samples from two more studies, resulting in a total sample of 325 posterior teeth. One operator had performed electrical resistance measurements on all teeth in the sample. Reproducibility was good: mean Pearson's correlation coefficient 0.89 (+/-0.05) for interexaminer correlation, and 0.86 (+/-0.12) for intra-examiner correlation, using log (resistance) as the result parameter. The correlation coefficient between log(resistance) and histological lesion depth for the large sample was -0.78 for all teeth, -0.64 for premolars, and -0.73 for molars. The regression line for molars was located below the regression line for premolars: at a hypothetical histology score of 2.5 (a dentine caries threshold) the estimated resistance threshold would be 507 kOmega for premolars, and 233 kOmega for molars. Converted to Electronic Caries Monitor (ECM) readings, the difference is about 1.4 on the ECM scale. It was concluded that the in vitro reproducibility of the described surface-specific method for electrical resistance measurement is very good, even for inexperienced operators. The correlation between measurements and histological lesion depth is moderate to good. The method is sensitive to electrode area differences, which will result in different clinical cut-offs for caries diagnosis in premolar and molar teeth.

Bicuspid↗

PubMedDate not supplied

Performance and reproducibility of a laser fluorescence system for detection of occlusal caries in vitro.

The diagnosis of occlusal caries at non-cavitated sites remains problematic, especially since clinical visual detection has limited sensitivity. Electrical methods of detection show considerable promise, but specificity is reduced. The aims of this in vitro study were: (1) to assess the validity of a new laser fluorescence device--the DIAGNOdent--(and compare the values with those of a fixed-frequency electrical device); (2) to determine the optimum cut-off points of the new device for different stages of the caries process, and (3) to assess the reproducibility of the new laser device. For validity and determination of optimum cut-off points, 105 extracted teeth with macroscopically intact occlusal surfaces were measured by a single examiner, using both the laser fluorescence device (on both moist and dried teeth) and an Electronic Caries Monitor. The teeth were subsequently examined histologically to determine the specificity, sensitivity and likelihood ratio at the D2 (caries extending through more than half of the enamel thickness) and D3 (caries involving dentin) levels. The values obtained for the laser device ranged from 0.72 to 0.87 (specificity), 0.76 to 0.87 (sensitivity) and 3.0 to 5.6 (likelihood ratio). Those for the ECM ranged from 0.64 to 0.78 (specificity), 0. 87 to 0.92 (sensitivity) and 2.4 to 4.1 (likelihood ratio). To determine intra- and interexaminer reproducibility of the DIAGNOdent, 11 dentists recorded two different measurements at the same site on a separate set of 83 extracted molar teeth, and these were compared using Cohen's kappa (at D2 and D3 levels) and Spearman's correlation coefficient. The average intra-examiner kappa scores were 0.88 (D2) and 0.90 (D3), with a Spearman correlation of 0.97. For interexaminer reproducibility, the average kappa values were 0.65 (D2) and 0.73 (D3), with a Spearman correlation of 0.84. It is concluded that for occlusal caries (1) the new laser device has a higher diagnostic validity than the ECM, and (2) in vitro, measurements using the device are highly reproducible. Thus, the laser device could be a valuable tool for the longitudinal monitoring of caries and for assessing the outcome of preventive interventions.

Dental Caries↗

PubMed1998

Epiluminescence microscopy versus clinical evaluation of pigmented skin lesions: effects of Operator's training on reproducibility and accuracy. Dermatology and Venereology Society of the Canton of Ticino.

BACKGROUND: An acceptable level of reliability is a prerequisite for the introduction of epiluminescence microscopy (ELM) into the diagnosis of pigmented skin lesions. OBJECTIVE: To assess the effects of a training program on the reproducibility and accuracy of ELM as compared to clinical evaluation. METHODS: Before and after the program, 48 clinical images and their ELM counterparts were independently evaluated by seven participants. Reproducibility was measured by the kappa index, accuracy by the rate of exact diagnoses (RED) assuming histology as a reference. RESULTS: We observed (i) no effect of training on clinical reproducibility, (II) an improved reproducibility of ELM diagnoses of non-melanocytic lesions (NML) and melanomas but not of melanocytic nevi (MN), (iii) a greater increase in the clinical RED of NML and melanomas compared with MN and (iv) a similar though more pronounced increase in the RED on ELM. CONCLUSIONS: The effects of training were greater for ELM as compared to clinical diagnosis, and for NML and melanomas as compared to MN.

Dermatology↗

PubMed1998

Reproducibility of optic disk topographic measurements with the Topcon ImageNet and the Heidelberg Retina Tomograph.

OBJECTIVE: To compare the reproducibility of optic disk measurements provided by an image analyzer and a scanning laser tomograph. METHODS: Ten images of the same eye of 10 normal volunteers were taken with the Heidelberg Retina Tomograph and with the Topcon ImageNet. Intraclass correlation coefficient (ICC) and coefficient of variation (CV) were used to evaluate the reproducibility of the measurements. RESULTS: Eleven parameters were analyzed with the Topcon ImageNet. Six parameters (55%) had ICC greater than 90%. Four parameters (36%) had CV less than 10%. Twelve parameters were evaluated with the Heidelberg Retina Tomograph. Nine parameters (75%) had ICC over 90%. Nine parameters (75%) had CV less than 10%. CONCLUSION: Both systems provided reproducible data. The optic disk parameters provided by the Heidelberg Retina Tomograph had a better reproducibility than those obtained from the Topcon ImageNet.

Adult↗

PubMed1999

Maximum static respiratory pressures in healthy elderly men and women: issues of reproducibility and interpretation.

BACKGROUND: Respiratory muscle strength is assessed using the static pressure generated at the mouth during a maximal inspiratory or expiratory effort [PImax and PEmax, respectively (MSRPs)]. Interpretation of MSRPs relies upon comparison with 'normal' values, but MSRPs show very weak associations with predictors such as physical characteristics. The influence of habitual physical activity upon MSRPs remains undefined. OBJECTIVES: We examined measurement reproducibility, as well as the influence of physical characteristics and habitual physical activity upon MSRPs in healthy elderly people. METHODS: MSRPs were assessed in 41 healthy subjects using a portable mouth pressure meter on two occasions, 1 week apart. Physical activity was assessed in 10 subjects by diary record. Pearson product-moment correlation coefficients were used to assess the association of MSRPs with other measured variables. RESULTS: There was good measurement reproducibility of MSRPs, with coefficients of reproducibility of 10.2 and 12.8% for PImax and PEmax, respectively. MSRPs showed statistically significant negative correlations with age, but correlations with physical characteristics were poor. In contrast, MSRPs were highly correlated with physical activity. CONCLUSIONS: We conclude that MSRPs can be measured reproducibly and that they decline with advancing age. Physical characteristics are not good predictors of MSRPs; this may be due to a strong confounding influence of physical activity making interpretation of measurements problematic. We suggest that the poor predictive power of physical characteristics indicate that reference to 'normal' values be made with caution and that it may be more appropriate to consider functional interpretations of MSRPs based upon factors such as lung and chest wall elastance.

Aged↗

PubMedDate not supplied

Improving the reproducibility of acoustic rhinometry in the assessment of nasal function.

Acoustic rhinometry readings are very position dependent, and it was hypothesized that this accounts for its relative lack of reproducibility on a day-to-day basis. Multiple readings on each visit were taken to investigate their impact, if any, on improving the day-to-day reproducibility of the method. Measurements of the minimal cross-sectional area of the nose as measured by acoustic rhinometry were studied in 10 subjects following nasal decongestion. For each individual, acoustic rhinometry was performed ten times. The ten recordings were repeated again, in an identical manner on a separate day. The subjects were repositioned and the nasal probes reinserted between each measurement. The mean coefficient of variation for minimal cross-sectional area readings in all 10 subjects was calculated as 9.92%. This is comparable to the day-to-day variability of acoustic rhinometry as measured by other workers and thus supports the hypothesis that the high measurement error of the device (rhinometer) is a function of positional variation during data acquisition. We were able to demonstrate a minimal gain in intervisit reproducibility by doing multiple recordings per person, with a plateau effect of reproducibility after 7 repeat readings.

Humans↗

PubMed2002

Accuracy and reproducibility of ultrasound measurements in obstetric management.

OBJECTIVE: The aim of this study was to assess the potential of ultrasonography as a routine diagnostic tool in obstetric management. SUBJECTS AND METHODS: For the investigation on interobserver reproducibility, 2 sonologists independently measured the biparietal diameter (BPD), femur length (FL), amniotic fluid index (AFI), and resistance index (RI) of the umbilical and middle cerebral arteries in 20 healthy pregnant women between 28 and 36 weeks of gestation using color and pulsed Doppler ultrasound. A second group of 10 healthy pregnant women between 30 and 35 weeks of gestation were examined to assess the level of intraobserver reproducibility of the Doppler and ultrasound measurements by 2 sonologists. For each patient in this group, the flow waveform was measured three times in succession. Calculations of the intraclass correlation coefficient (Ri) were used to determine the levels of reproducibility. The agreement was considered acceptable only when the Ri value was > or = 6. RESULTS: The interobserver Ris for BPD, FL, AFI, and RI of the umbilical and middle cerebral arteries were 0.93, 0.8, 0.58, 0.49 and 0.56, respectively. The intraobserver Ris of the 2 sonologists in BPD, FL, and RI of umbilical artery were >0.6, whereas those in AFI and RI of middle cerebral artery were <0.6. CONCLUSIONS Both the interobserver and intraobserver reproducibilities of BPD and FL were clinically acceptable, but not in the AFI and RI of umbilical and middle cerebral arteries.

Adult↗

PubMedDate not supplied

Intraindividual reproducibility of postprandial hypotension.

BACKGROUND: Postprandial hypotension (PPH) is increasingly recognized as a common cause of falls and syncopes in the elderly. The diagnosis of PPH is based on the measurement of meal-induced blood pressure (BP) changes. Although the problem of intraindividual reproducibility of PPH is of clinical importance, it has not been extensively studied. OBJECTIVE: To assess the intraindividual reproducibility of PPH. METHODS: 50 patients (42 women and 8 males, 83 +/- 8 years) were included in the study. To evaluate PPH, we measured the BP before and every 15 min for 2 h after the start of a standardized mixed meal. The PPH was defined as a decrease in systolic BP of 20 mm Hg or more. Three sets of BP were obtained for each subject on 2 successive days: (1) between 08.00 and 10.00 h and (2) between 16.00 and 18.00 h on the 1st day and (3) between 08.00 and 10.00 h on the 2nd day. RESULTS: 32 participants (64%) experienced PPH on at least one test. Among them, 19 (38%) had PPH on the first test, 16 (32%) had PPH on the second test, and 21 (42%) had PPH on the third test. The intraindividual reproducibility of PPH was good when the results of the two morning tests were compared together (kappa coefficient = 0.6), but was low when the morning test results were compared with the afternoon test results of the 1st day (kappa coefficient = 0.1). CONCLUSIONS: Because of the good reproducibility of postprandial BP changes, we conclude that the diagnosis of PPH may be based on a single standardized test. However, the test must be performed under circumstances (time of the meal, medications) similar to those in which the symptoms occurred.

Accidental Falls↗

PubMed2003

Reproducibility of cerebral near infrared spectroscopy in neonates.

Near infrared spectroscopy (NIRS) allows to study cerebral hemodynamics and oxygenation in neonates, which may be useful for early detection of cerebral hypoxemia. So far this method is not reliable enough to be used clinically. Reproducibility is one of the prerequisites for reliable quantitative monitoring. The aim of this study was to assess the reproducibility of the NIRS parameters HbO(2) and HbD (oxygenated and deoxygenated hemoglobin concentration) and the derived NIRS parameters HbT (tissue hemoglobin concentration, HbT = HbO(2) + HbD) and rSO(2) (regional cerebral oxygen saturation, rSO(2) = HbO(2)/HbT). Two observers repeated a total number of 500 measurements in 25 neonates. Additionally, a baseline measurement was done to assess the physiological variation in every neonate. For all NIRS parameters, the inter-patient variance contributed most to the total variance, while the interobserver variance was the smallest variance component. The cerebral oxygen saturation parameter rSO(2) showed a good reproducibility, with an inter-measurement variance slightly but not significantly higher than the physiological baseline variation. The NIRS concentration parameters HbO(2), HbD, and HbT were less reproducible, with significant variation due to repeated sensor replacement. However, for cerebral oximetry rSO(2) is likely to be more important than the other NIRS parameters, so that NIRS has the potential to become a quantitative cerebral monitoring method.

Brain↗

PubMed2006

Intersession reproducibility of retinal nerve fiber layer thickness measurements by GDx-VCC in healthy and glaucomatous eyes.

BACKGROUND: To assess intersession reproducibility of retinal nerve fiber layer (RNFL) thickness measurements on scanning laser polarimetry with variable corneal compensation (GDx-VCC) in a sample of healthy subjects and glaucoma patients. METHODS: One eye each from 29 healthy and 29 glaucomatous subjects was selected and underwent RNFL scanning by the same operator at baseline and 1 week later. Glaucoma diagnosis relied on the presence of a reproducible defect on automated perimetry. GDx-VCC parameters considered were those available on page 1 of the printout [TSNIT average and standard deviation (SD), superior and inferior average (SA, IA), Nerve Fiber Indicator]. Reproducibility was assessed by calculating coefficient of variation and intraclass correlation coefficient separately for the two groups and for each parameter. The percentage of eyes with an intersession difference in thickness parameters of more than 5% was also calculated. RESULTS: Coefficient of variation was <6% for TSNIT average, SA and IA in both groups. Corresponding values for TSNIT SD in healthy subjects and in glaucoma patients were 13.7 and 11.4%, respectively, whereas for Nerve Fiber Indicator they were 82.9 and 13.3%. Intraclass correlation coefficient ranged from 0.794 to 0.907 in healthy subjects and from 0.924 to 0.972 in glaucoma patients. In healthy subjects, TSNIT average, SA and IA intersession difference was 5% or less in 55-69% of eyes, whereas the value for TSNIT SD was 34.5%. Corresponding values in glaucomatous eyes ranged from 69 to 79.3% for TSNIT average, SA and IA and was 37.9% for TSNIT SD. CONCLUSIONS: Intersession reproducibility of RNFL thickness measurements on GDx-VCC is high, both in healthy and in glaucomatous eyes. In a few cases, however, intersession variation may be larger than 10%. Caution is necessary while interpreting these changes during follow-up, in order to separate physiological variability from real RNFL thickness variations.

Aged↗

PubMedDate not supplied

Improved reproducibility of the 'large-window' method of assessing transcapillary and interstitial fluorescein diffusion in the skin in healthy subjects and in subjects with insulin-dependent diabetes mellitus.

The transcapillary and interstitial diffusion of intravenously administered sodium fluorescein is used as a marker for capillary permeability. Fluorescein diffusion has been expressed by different parameters with reported coefficients of variation of 14-20%. Aim of the present study is to select a parameter which combines excellent reproducibility with the potential for discriminating insulin-dependent diabetic patients from healthy subjects. We performed three experiments to assess day-to-day reproducibility: 5 healthy subjects were measured twice, 1 healthy subject was measured 6 times and 1 subject with insulin-dependent diabetes mellitus was measured 5 times. We averaged the relative fluorescence light intensity (IREL(t)] from dye arrival until a certain time point [IAV(t)], instead of using the relative intensity at one time point. IAV (7 min) showed markedly improved reproducibility, expressed as geometric mean of the coefficients of variation of the three separate experiments: 10%. In addition, a group of 12 insulin-dependent diabetic subjects was compared with 12 healthy control subjects. Median IAV (7 min) was 69.5% (95% CI: 65.3-78.1%) in the diabetic subjects and 54.9% (95% CI: 52.1-60.0%) in the control subjects (p < 0.001). Since IAV (7 min) combines excellent reproducibility with a good discriminating power, we advise its use in further studies.

Adult↗

PubMed1994

Factors affecting ambulatory blood pressure reproducibility. Results of the HARVEST Trial. Hypertension and Ambulatory Recording Venetia Study.

To assess the reproducibility of ambulatory blood pressure, we recorded 24-hour blood pressure twice 3 months apart in 508 hypertensive subjects participating in the HARVEST trial using a noninvasive technique. Blood pressure was measured every 10 minutes during the daytime and 30 minutes during the nighttime. Reproducibility was better for ambulatory than for office blood pressure. It was greater for 24-hour than for daytime blood pressure and lowest for nighttime blood pressure. The reproducibility of blood pressure variability (standard deviation) was poorer than that of the average values. A small but significant decrease in average daytime blood pressure (-0.8/-1.0 mm Hg) and virtually no change in nighttime blood pressure (+0.5/+0.1 mm Hg) were observed at repeat recording. Reducing the sampling rate by 50% caused only a small impairment of the reproducibility indexes of both the average values and variability. Blood pressure reduction was greater during the first and last hours of the recordings, indicating an effect of the hospital environment on the between-monitoring difference. Changes in body weight (-0.7 kg, P = .006, at repeat recording) were related to those of 24-hour diastolic blood pressure (P < .05). In conclusion, patient reaction to medical environment and changes of body weight seem to account for most of the change in 24-hour blood pressure that occurs over a 3-month period.

Adolescent↗

PubMed2005

Reproducibility of retinal nerve fiber thickness measurements using the stratus OCT in normal and glaucomatous eyes.

PURPOSE: To determine the reproducibility of Stratus Optical Coherence Tomography (OCT) retinal nerve fiber layer (RNFL) measurements around the optic nerve in normal and glaucomatous eyes. METHODS: One eye was chosen at random from 88 normal subjects and 59 glaucomatous subjects distributed among mild, moderate, and severe glaucoma, determined by visual field testing. Subjects underwent six RNFL thickness measurements performed by a single operator over a 30-minute period with a brief rest between sessions. Three scans were taken with the high-density Standard RNFL protocol, and three were taken with the Fast RNFL protocol, alternating between scan protocols. RESULTS: Reliability, as measured by intraclass correlation coefficient (ICC), was calculated for the overall mean RNFL thickness and for each quadrant. The ICC for the mean Standard RNFL thickness (and lower 95% confidence interval [CI]) in normal and glaucomatous eyes was 0.97 (0.96 CI) and 0.98 (0.97 CI), respectively. The ICC for the mean Fast RNFL thickness in normal and glaucomatous eyes was 0.95 (0.93 CI) and 0.97 (0.95 CI), respectively. Quadrant ICCs ranged between 0.79 and 0.97, with the nasal quadrant being the least reproducible of all four quadrants, using either the Standard or Fast RNFL program. The test-retest variability ranged from 3.5 microm for the average RNFL thickness measurements in normal eyes to 13.8 microm for the nasal quadrant measurements in glaucomatous eyes, which appeared to be the most variable. CONCLUSIONS: Reproducibility of RNFL measurements using the Stratus OCT is excellent in normal and glaucomatous eyes. The nasal quadrant appears to be the most variable measurement. Standard RNFL and Fast RNFL scans are equally reproducible and yield comparable measurements. These findings have implications for the diagnosis of glaucoma and glaucomatous progression.

Adult↗

PubMed1996

Reproducibility of Doppler ultrasound measurements.

PURPOSES: The reproducibility of Doppler ultrasound measurements was studied in a group of radiologists with different experience of such measurements. MATERIAL AND METHODS: The 12 participating radiologists measured peak systolic velocity (PSV), resistance index (RI), and pulsatility index (PI) from 3 arteries and PSV alone in one artery of a healthy person under standardized circumstances. Each participant repeated the measurements 10 times. RESULTS: Significant (p < 0.005) interobserver variation was seen in all of the variables, with an up to 14-fold difference in the PSV values measured and most variation resulting from differences between observers. The reproducibility of RI was better, most variation being within observers. Experience improved the reproducibility of the Doppler US measurements. Significant difference (p < 0.05) in Doppler US measurements was seen between the 3 experience groups. The difference was marked between the highly experienced and the medium experienced group when the variances of the measured values of PSV, RI, and PI from all 4 arteries were combined. CONCLUSION: The reproducibility of Doppler ultrasound measurements is poor. The value of the method is questionable.

Adult↗

PubMedDate not supplied

Reproducibility of anatomic tibial landmarks for anterior cruciate ligament reconstructions.

We evaluated the reproducibility of landmarks used for accurate anatomic placement of the tibial tunnel in anterior cruciate ligament reconstruction. Landmarks evaluated were the medial tibial eminence, the posterior cruciate ligament, the "over-the-back" position, the true posterior border of the tibia, and the posterior border of the lateral meniscus. Forty-two pairs of cadaveric knees were dissected, and anatomic measurements were made regarding the anterior cruciate ligament insertion and these various landmarks. Statistical analysis was used to confirm reproducibility and significance. Measurements based on the medial tibial eminence and posterior border of the meniscus were particularly erratic. The most reproducible anatomic landmark was the posterior cruciate ligament. The anterior border of the posterior cruciate ligament was consistently 6.7 mm posterior to the posterior border of the anterior cruciate ligament and 10.9 mm posterior to the central sagittal insertion point of the anterior cruciate ligament. The over-the-back position was consistently in contact with the anterior border of the posterior cruciate ligament if the knee was flexed with a posterior-directed force applied. In this position, the over-the-back position was equally reproducible as compared with the posterior cruciate ligament. Measurements gauged from the true posterior border of the tibia gave a second rigid bony landmark but with a wider standard deviation than the posterior cruciate ligament-based landmarks. The relative anterior-posterior dimension of the tibia did not correlate with the relationship between the anterior cruciate ligament and other anatomic landmarks.

Anterior Cruciate Ligament↗

PubMedDate not supplied

Chlamydia pneumoniae in PBMC: reproducibility of the OMPA nested touchdown PCR.

The aim of our study was to evaluate whether the replicate PCR testing may provide more accurate estimates of C. pneumoniae DNA prevalence in PBMC of patients undergoing carotid endarterectomy. Clinical sensitivity and reproducibility of ompA nested touchdown PCR was also performed. Clinical sensitivity and reproducibility was examined by testing C. pneumoniae-negative PBMC spiked with serial dilutions of semipurified C. pneumoniae elementary bodies (from 8 to 0.002 IFU/ml). Detection of C. pneumoniae DNA was performed by ompA nested touchdown PCR. Each clinical and spiked PBMC DNA specimen was analyzed in replicates of 1, 3, 5 and 10. PCR results of serial dilutions of C. pneumoniae DNA performed in replicates of 10 were analysed by probit analysis. C. pneumoniae DNA was detected in 14 of the 30 (46.7 %) PBMC clinical specimens examined when 10 replicates were tested. When we analyzed 1, 3 and 5 replicates, 4 (13.3 %), 7(23.3 %), 12(40 %) of the 30 specimens were positive, respectively. The limit of detection of ompA nested PCR touchdown was 0.008 IFU/ml when 10 replicates were tested. The ompA nested PCR had reproducibility scores of 10 for 10 from 8 to 4 IFU/ml concentration, but scores decreased for smaller numbers of IFU/ml. Our results showed that repeat testing of the same specimen increased clinical sensitivity as well as reproducibility of the ompA nested touchdown PCR. In conclusion the replicate PCR testing improves the performance of ompA nested touchdown PCR and provides a more accurate estimates of the prevalence of C. pneumoniae in PBMC of patients with atherosclerotic cardiovascular disease.

Bacterial Outer Membrane Proteins↗

PubMed2003

Reproducibility of exhaled nitric oxide measurements in healthy and asthmatic adults and children.

Airway inflammation in asthma is not measured routinely in clinical practice. Fractional exhaled nitric oxide (FE(NO)), a marker of airway inflammation, is increasingly used as an outcome measure in asthma intervention studies and yet the reproducibility of FE(NO) measurements is unknown. The reproducibility, day-to-day, diurnal variation and perception of standardised FE(NO) measurements were examined in 59 subjects (40 children aged 7-13 yrs and 19 adults aged 18-60 yrs), both healthy (n=30) and with mild (n = 29) asthma. FE(NO) was measured on five consecutive days (four measurements on the same day) for adults and twice on the same day for children. The coefficient of reproducibility expressed as the mean pooled standard deviation (n = 59, 675 estimations) was 2.11 parts per billion (ppb) and intraclass correlation coefficient was 0.99 in both children and adults. FE(NO) was significantly higher in asthma subjects (32.3 ppb) than in healthy subjects (16.3 ppb). There was no diurnal or day-to-day variation, or a learning effect, as the result of FE(NO) measurements were identical at results of the beginning and at the end of the study. It was concluded that fractional exhaled nitric oxide measurements are simple, reproducible, free from diurnal and day-to-day variation, and acceptable by both healthy and asthmatic adults and children, as a part of their routine visit to a physician.

Adult↗