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PubMed1989

Reproducibility of systolic and diastolic time intervals in normal humans: an important issue in clinical cardiovascular pharmacology.

The purpose of this study was to evaluate the long-term variability and reproducibility of systolic and diastolic time intervals in human subjects. Ten healthy volunteers underwent serial determinations of systolic and diastolic time intervals and, as internal physiologic standards, heart rate (HR), systemic blood pressures, and resting oxygen consumption (VO2). The protocol lasted 1 month and measurements were made on days 1, 2, and 30. No statistically significant differences were found in the various systolic time interval parameters, percentage of diastolic time, heart rate, systolic blood pressure (SBP) and resting oxygen consumption for the 3 study days. Diastolic blood pressure tended to rise slightly (p = 0.07) from day 1 to day 30. The average coefficients of variation for systolic and diastolic time interval parameters in individual study subjects ranged from 1.2 to 7.0%, whereas those for resting physiologic data ranged from 5.3 to 8.5%. In normal human subjects, systolic and diastolic time intervals are highly reproducible, with acceptable variation over time; these measurements should be thought of as possessing reproducibility equal to or greater than the resting physiologic parameters of HR, systemic blood pressure and oxygen consumption.

Adult↗

PubMed1989

[Reproducibility of urine strip reactions in medical patients].

Before a method of investigation is introduced in the daily clinical routine, its reproducibility and correctness must be proved. In the present investigation, the reproducibility of urine stix reactions for glucose, haemoglobin and protein were assessed. The urine stix tests were carried out on freshly voided urine from 30 patients selected at random by three junior nurses with seniorities of one, five and nine years. Complete inter- and intraobserver agreement was found for glukose and haemoglobin whereas the reproducibility for protein was unsatisfactory.

Evaluation Studies as Topic↗

PubMed1989

Representativity and reproducibility of DNA malignancy grading in different carcinomas.

The reproducibility of the determination of the "DNA malignancy grade" (DNA-MG) was tested in 56 carcinomas of the colon, breast and lung while its representativity was tested on 195 slides from 65 tumors of the colon, breast and lung. DNA measurements were performed on Feulgen-stained smears with the TAS Plus TV-based image analysis system combined with an automated microscope. The variance of the DNA values of tumor cells around the 2c peak, the "2c deviation index" (2cDI), was taken as a basis for the computation of the DNA-MG, which ranges on a continuous scale from 0.01 to 3.00. The representativity, analyzed by comparison of the DNA-MGs measured in three different areas of the same tumor greater than or equal to 1.5 cm apart from each other, yielded an 81% agreement. No significant differences between DNA-MGs of these areas were found. The intraobserver and interobserver reproducibilities of the DNA grading system, investigated by repeated DNA measurements, were 83.9% and 82.2%, respectively. In comparison, histopathologic grading of the 27 breast cancers studied yielded 65% intraobserver and 57% interobserver reproducibilities and 66% representativity.

Breast Neoplasms↗

PubMed1988

[Reproducibility of ergometric parameters at the ischemic threshold: study of 160 patients with effort coronary insufficiency].

To assess the reproducibility of ergometric parameters at the ischemic threshold, 160 patients, with coronary artery disease and exercise-induced S-T segment depression (102 with previous AMI), were evaluated by means of two control exercise tests performed, in pharmacological wash-out, on different days within 48 hours. The mean values of work load (WL), heart rate (HR) and double product (DP) did not show any statistical difference between the two exercise tests at 0.1 mV S-T depression (ischemic threshold), recorded by a computer assisted electrocardiograph system (Marquette CASE); on the contrary blood pressure (BP) slightly, but significantly (p less than 0.05) decreased at the second test (173.9 +/- 27.2 vs 179.8 +/- 25.8). The variability of the DP values in each subject at 0.1 mV S-T depression, expressed as numerical (delta) and percentage (delta %) differences, exhibited normal distributions. The delta DP showed a mean +/- 1 SD of -157.5 +/- 3271.5 beats x mmHg/min and the delta % DP a mean of +/- 1 SD of 1.46 +/- 16.4%. The values within a standard deviation from the mean (from +3114 to -3429 when numerical differences and from +17.8 to -14.9 when percentage differences) were used for defining the reproducibility of the ischemic threshold. No correlation was found between the delta % DP and the percentage differences in work load at the ischemic threshold. So, DP being more strictly related to MVO2, appears more apt in defining the ischemic threshold reproducibility. A good correlation (r = 0.821) was found between delta DP and delta % DP.(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Disease↗

PubMed1986

[Ambulatory recording of blood pressure. Study of the reproducibility of findings in 25 subjects].

The reproducibility of a novel ambulatory blood pressure (B.P.) monitoring was tested, for clinical trial in hypertension. The spacelabs apparatus is based on standard auscultatory and oscillometric blood pressure measurements. Ten normotensive patients and 15 hypertensive patients were investigated as follows: their blood pressure was monitored twice over a 24 hr period at an interval of 30 and 15 days respectively. The monitoring data were expressed as the mean of the average blood pressure over day-time (7 hr-22 hr) and 24 hr as well as 24 hr. B.P. profiles (means of 4 measurements per hour). The statistical analysis of the two subpopulations of patients showed a satisfaction reproducibility of both the 24 hr B.P. curves (normotensive patients: PAS: r = 0.94; PAD: r = 0.92; Hypertensive patients PAS: r = 0.82; PAD: r = 0.64 p less than 0.001). and blood pressure levels (normotensive patients: J1: 113 +/- 10/70 +/- 6 mmHg; J30: 110 +/- 10/68 +/- 6 mmHg. Hypertensive patients: J1: 150 +/- 10/98 +/- 9 mmHg; J15: 155 +/- 15/96 +/- 8 mmHg). In contrast, analyzing each patient individually exhibited a correct reproducibility of the B.P. levels but the 24 hr--profiles of either the diastolic or systolic blood pressure could not be correlated with sufficient reliability (normotensive patients: 7 times out of 10 for PAS, and 4 times out of 10 for PAD; hypertensive patients: 5 times out of 15 for PAS, and 3 times out of 15 for PAD). In addition, the patient activity, should be carefully controlled during ambulatory blood pressure measurements.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1987

Intranasal and intravenous administration of desmopressin: effect on F VIII/vWF, pharmacokinetics and reproducibility.

A comparison was made of intranasal administration of 300 micrograms desmopressin (DDAVP) by spray, with intravenous administration of 0.2, 0.3 and 0.4 microgram DDAVP/kg in 10 healthy volunteers. The effect of DDAVP was measured on F VIII/vWF complex and on plasminogen activator release. In addition, plasma levels of DDAVP were determined using a specific and sensitive radioimmunoassay. Moreover, the reproducibility of the spray effect in 10 healthy volunteers was tested after administration of 300 micrograms DDAVP intranasally by spray on 5 different occasions. Plasma levels of DDAVP showed a clear dose-response with the maximum levels at 0.4 microgram/kg i.v. The effect of the spray approximated the 0.2 microgram/kg response. However, the maximum response in both F VIII/vWF complex and plasminogen activator release was obtained after 0.3 microgram/kg i.v. The response to 0.4 microgram/kg i.v. was not significantly different from the response to 0.3 microgram/kg indicating that maximum stimulation was reached with 0.3 micrograms/kg. There was no correlation between plasma levels of F VIII/vWF and DDAVP indicating that the biological response to DDAVP is subjected to saturation kinetics. The reproducibility of the effect of the spray dose on VIII:C was 21% (c.v.) and 27% for the intra-individual and inter-individual variation, respectively, and compared favorably with intravenous administration. Intranasal DDAVP (300 micrograms) is as effective as 0.2 micrograms/kg intravenously and provides an accurate, reproducible and convenient alternative to parenteral administration.

Administration, Intranasal↗

PubMed1988

Reproducibility of the Early Cataract Detector (Kowa ECD 2000).

We conducted a reproducibility study on the Kowa Early Cataract Detector, a laser light scattering spectroscope that determines the diameter of particles within the lens and designed to quantify changes in particle size in early cataracts. We found good reproducibility in the nuclear region (where changes are homogeneous), but found poor reproducibility in the cortical region (where changes are heterogeneous). We advise careful evaluation of other similar devices before extensive use.

Cataract↗

PubMedDate not supplied

Reproducibility of diagnostic results by a multivariate computer ECG analysis program (AVA 3.5).

Reproducibility of the AVA program (version 3.5) was tested (1) by analyzing the same analog tracing 10 times in 150 patients, and (2) by studying the influence of 12 different sets of prior probabilities (PRP), using the digital data from a total of 2718 patients. The same QRS-T diagnosis plus or minus 8 percentage points was found in patients with high posterior probabilities. Variability for the P wave diagnosis was twice as high as for QRS-T results. Failure to select the appropriate set of PrP markedly influenced reproducibility. This was especially true for right ventricular hypertrophy and pulmonary emphysema. 'Mispriorizing' in a subgroup of 199 patients with well-documented myocardial infarction lowered the total number of correct ECG diagnoses on the average between 4.8 and 35%. These results are inherent to Bayes' theorem where PrP are used to achieve minimum assignment error in populations, but where Prp errors may result in wide classification discrepancies. Without errors in PrP reproducibility by the VA program was found to be very high.

Analysis of Variance↗

PubMed1986

Reproducibility of early asthmatic response to Cladosporium herbarum.

The reproducibility of the early asthmatic response after bronchial challenge with cladosporium herbarum was studied in 5 adult asthmatics. Four bronchial challenges were done in randomized order with an interval of one week. The four challenges were: cladosporium herbarum, cladosporium herbarum, histamine and saline. The bronchial challenges were done double-blind. Cladosporium herbarum was inhaled in the following concentrations (w/v): 1:100000, 1:10000, 1:1000 and up to 1:100. Histamine was inhaled in the following concentrations: 0.3, 0.6, 1.2 and up to 2.4 mg/ml FEV1 was measured before every inhalation and 2, 5, 10 min after. If FEV1 dropped greater than 20% after inhalation, the challenge was assessed as positive and the provocation on that day was stopped. The provocation was assessed as negative if this fall was not seen after the fourth inhalation. Two patients with positive skin test to cladosporium herbarum had reproducible early asthmatic response after inhalation of the antigen, they reacted to inhaled histamine and one of them presented an early asthmatic response after inhalation of saline. Three patients with negative skin test to cladosporium herbarum had an early asthmatic response after inhalation of the antigen on two out of six provocations, a response which was not reproducible. None of the three responded to saline. It is concluded that inhalation challenge with cladosporium herbarum may be more confusing than helpful in the diagnosis of early asthmatic response to this antigen, as patients with negative history and negative skin test sometimes present a positive bronchial challenge.

Adult↗

PubMed1986

Reproducibility of the late asthmatic response.

The reproducibility of the late asthmatic response after bronchial challenge with cladosporium herbarum was studied in five adult asthmatics. Four bronchial challenges were done in randomized order with an interval of one week. The four challenges were: cladosporium herbarum, cladosporium herbarum, histamine and saline. The bronchial challenges were done double-blind. Up to four inhalations of the substance were given on one day. Cladosporium herbarum was inhaled in concentrations of 1:100000, 1:10000, 1:1000 and up to 1:100 w/v. Histamine was inhaled at concentrations of 0.3, 0.6, 1.2 and up to 2.4 mg/ml. The provocation was stopped if FEV1 dropped greater than 20% up to 10 min after the inhalation, or after the four inhalations. Ventilatory capacity was measured with one h intervals up to six h after the last inhalation. One patient with positive skin test to cladosporium herbarum had no late asthmatic reaction after inhaling a dose of antigen which gave an early asthmatic response. One patient with positive skin test and early asthmatic response after inhalation of cladosporium presented late asthmatic response after one provocation, but this response was not reproducible. None of the two patients with negative skin test had late asthmatic response after inhalation of the antigen, nor had they late asthmatic response after inhalation of saline or histamine. One patient with negative skin test and no early asthmatic response to inhaled cladosporium, showed reproducible late asthmatic response after antigen inhalation. This patient also presented late asthmatic response after saline inhalation, but not after histamine inhalation. It is concluded that late asthmatic response should be defined better than of fall from baseline greater than 20%.

Adult↗

PubMed1987

Reproducibility of results in "near-replicate" carcinogenesis bioassays.

Reproducibility of results was examined in 70 "near-replicate" comparisons consisting of 2 or more long-term carcinogenesis bioassays of the same chemical administered by the same route and using the same sex and strain of rodent. Overall, there was good reproducibility of positivity, target site, and carcinogenic potency in hamsters, mice, and rats. The published authors' opinions about whether the test was positive disagreed in only 9 of the 70 comparisons. Among the 35 comparisons in which all tests of the chemical were positive, 33 of the near-replicates had at least 1 identical target site. The carcinogenic potency values estimated from near-replicate tests in these 35 comparisons were within a factor of 2 of each other in 40% of the comparisons, within a factor of 5 in 80%, and within a factor of 10 in 90%. For the few cases in which the carcinogenic response was not reproduced, analyses suggest two explanations: In mice the discrepant cases tended to have shorter experiment times than average; in both rats and mice the discrepant results tended to be tests of weakly active compounds.

Animals↗

PubMed1987

[Reproducibility of anatomo-pathological diagnoses: use of the kappa-test in histo-prognostic grading of soft tissue sarcomas in adults].

In pathology, reproducibility of lesional diagnostic and classification is not perfect, particularly when dealing with rare tumors like soft-tissue sarcomas, the classification of which is complex. Reproducibility among many independent observers can be well appreciated by kappa statistics, which take into account the agreement rate expected by chance only. A study of the reproducibility of histological classification and grading of 25 soft-tissue sarcomas by 15 pathologists showed that the agreement was better for the grading. A review of some other applications of kappa statistics in pathology reported in the literature is presented.

Adult↗

PubMed1986

The reproducibility of VO2max, ventilatory, and lactate thresholds in elderly women.

The reproducibility of VO2max, ventilatory, and lactate thresholds in elderly women. Med. Sci. Sports Exerc., Vol. 18, No. 4, pp. 425-430, 1986. This investigation examined the reproducibility of maximal (VO2max) and submaximal measures of fitness for elderly women. Eight subjects [age (yr): mean = 80.6 +/- 3.7; range = 73-86] volunteered to repeat three continuous, incremental maximal effort treadmill tests. Blood lactate determinations were made for each increment from blood samples taken from an indwelling venous catheter located in the back of the hand. Average VO2max values (ml X min-1 X kg X l-1) were 13.21 + 1.95 for test 1, 13.44 +/- 1.83 for test 2, and 13.62 + 2.95 for test 3. In all but one subject, a threshold was not definable by either ventilatory or lactate measurements. Maximal lactate values were low, with the average values for tests 1, 2, and 3 being 1.89, 1.46, and 1.86 mmol X l-1, respectively. The data demonstrates that VO2max is reproducible for older women and can, therefore, be used for fitness assessment and exercise prescription. The use of ventilatory or lactate thresholds as submaximal measures of fitness or as minimal intensities for exercise prescription was determined not to be applicable for women in the eighth and ninth decades of life.

Aged↗

PubMed1986

The contribution of cytochemistry and immunophenotyping to the reproducibility of the FAB classification in acute leukemia.

Intraobserver and interobserver reproducibility of the FAB classification was assessed for two independent observers whose decisions are acted on for treatment of patients with acute leukemia in the Hamilton region. Intraobserver reproducibility was assessed for Wright-stained preparations that were examined independently on two consecutive occasions at least 2 weeks apart. A third reading was performed with Wright stain and cytochemical data, and the fourth reading was done with addition of immunophenotype data. Concordance was calculated using a statistic that corrects for chance-expected agreement (k), and a weighted statistic that takes into account the seriousness of disagreements was used. Samples were available for morphological and cytochemical assessment on 105 patients, and immunophenotype data were available on 93 specimens. Intraobserver concordance was 64.8% and 70.5% for observers A and B, respectively, with kappa values of .56 and .62. There were 37 discordant readings for observer A and 31 for observer B, with each observer discordant between lymphocytic:nonlymphocytic phenotypes in ten cases. Concordance between observers was 63% (k = .54) and 72% (k = .65) for each of two separate readings for Wright-stained preparations only. Reproducibility improved to 89% (k = .86) when cytochemistry was added. When immunophenotype information was provided in addition to Wright-stained and cytochemical preparations, the agreement was 99%. Lymphocytic:nonlymphocytic discordance between observers occurred on nine occasions when Wright-stained preparations only were available and four times when cytochemistry was added; it did not occur with immunophenotyping. The study suggests that immunophenotyping, when added to morphological assessment of acute leukemia, may contribute substantially to agreement between observers.

Antigens, Neoplasm↗

PubMed1979

Reproducibility of biotypes using enterotubes.

Using both stock and clinical isolates, the Enterotube system was examined for reproducibility of its biotype identification. Fifty stock strains of Enterobacteriaceae were tested on each of 22 separate days (interrun evaluation), and ten Enterotubes per strain were inoculated from one subculture (intrarun evaluation). It was found that 2 of the 50 strains (4 percent) demonstrated reproducibility of biotypes, defined as no variation in the results of the 22 interrun Enterotubes. Twenty-one of the 50 strains (42 percent) demonstrated reproducibility of biotypes, defined as no variation in the results of the ten intrarun Enterotubes. In addition, 20 replicate Enterotube biotype identifications were performed on each of 114 urine cultures which had greater than 10(5) morphologically identical colonies per milliliter of urine. Forty-two of these 114 clinical urine cultures (34 percent) demonstrated no variation in biochemical test results with the 20 replicate Enterotubes. In 47 (44 percent) of the 20 replicate urine cultures, one biochemical test result varied. Two or more biochemical test results were different in the 20 Enterotubes from 25 (22 percent) of the urine cultures.

Bacteriological Techniques↗

PubMed1986

Continuous 24 hour intragastric pH monitoring: focus on reproducibility in duodenal ulcer patients. A preliminary report.

Continuous 24 h intragastric pH monitoring is increasingly recommended for deciding which is the most appropriate regimen and dosage of new gastric antisecretory drugs. In order to assess its reproducibility, we have repeated the test twice on consecutive days in six patients with endoscopically proven duodenal ulcers because this type of patient seems to be the most suitable for studies on the efficacy of the above mentioned therapy. No patient received medication during the two examination days. Our data showed there was no significant difference (t = 0.31, p = 0.76) between the 24 h areas under the curve of pH profiles of the first day compared with those of the second (mean +/- SD : 3.152 +/- 681 vs 3.073 +/- 1,122). The lack of significant difference (p = 0.20) between the mean times elapsed at the various pH levels during the first and second days was further proof of the reproducibility of the method. As wells these results suggest that day-to-day reproducibility of the technique is good in duodenal ulcer patients. Therefore, its repeated use on the same patient to investigate the effects of various drugs and their different dosages on gastric acidity appears to be reliable.

Adult↗

PubMed1985

Reproducibility of nucleolar measurements in human intraocular melanoma cells on standard histologic microslides.

The standard deviation of nucleolar area (SDNA), as determined by semiautomated measurement of routinely prepared histologic sections, has been shown to be an effective predictor of mortality for human intraocular melanoma. One hundred cases of this tumor underwent two independent determinations of SDNA by each of two technicians using the same device. One technician performed the two measurements within two months, the other within three weeks. Analysis of these 400 values revealed the following: the more experienced of the two technicians achieved an acceptable level of reproducibility in determining SDNA; the less-experienced technician achieved a lower level of reproducibility; a systematic bias was found upon comparing SDNA values of the two technicians; and this bias can be partially corrected by applying a linear transform. These findings support the value of SDNA as a practical clinical measure of malignant potential for intraocular melanoma but also suggest that experience can enhance the reproducibility of a technician's measurements.

Cell Nucleolus↗

PubMed1985

[Reproducibility of the flow-volume indices of healthy persons and patients with lung diseases].

Reproducibility of the flow-volume indicators at forced expiration and inspiration was calculated during examination of 210 healthy subjects and 420 patients with different pulmonary diseases. Reproducibility of the flow-volume indicators of the median and end part of the forced expiration which reflect largely the function proper of the patency of the distal parts of the bronchial tree was essentially higher in patients and tended toward increase with a rise in the degree of ventilation abnormalities. Reproducibility of the conventional spirographic parameters in healthy subjects and patients with ERF abnormalities did not differ whatever their character and degree.

Adult↗