Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “reproducibility”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMed1997

How reproducible is the topographical distribution of EEG amplitude?

If topographical EEG is to be a useful tool for localising cerebral processes, then the results of the same, or closely similar experiments, using different samples should yield similar results. Although the reliability of EEG is well established in other ways, there is little available data on the reproducibility of EEG topography across experiments. The aim of this study was to determine the reproducibility of topographical EEG by comparing the results of two independently conducted experiments. EEG was recorded during an Eyes Open baseline and a motor task condition (the Luria finger opposition task) in two independent samples of healthy subjects. EEG was recorded in 2.56-s epochs and analysed by FFT into conventional theta, alpha and beta 1 frequency bands. The EEG amplitude for each subject in each frequency range was averaged over a minimum of 60 s. Separate group averages for each sample were calculated and the resulting topographical distributions of electrical potential and current density were compared. The results indicated that the reproducibility of electrical potential in the theta and beta 1 frequency ranges was extremely poor and only approached acceptable levels in alpha. Reproducibility of current source density was poor in all frequency ranges. Although some improvement in reproducibility was obtained following spatial smoothing for alpha potential, the highest reproducibility achieved was only 0.65. Reasons for the poor reproducibility of topographical EEG and the implications of these findings are discussed.

Adolescent↗
PubMed2001

Reproducibility of contrast-enhanced transrectal ultrasound of the prostate.

Transrectal three-dimensional (3-D) contrast-enhanced power Doppler ultrasound (US) is a novel technique for studying possible prostate malignancy. Before studies can be performed to investigate the clinical validity of the technique, reproducibility of the contrast US studies must be proven. Reproducibility of contrast US was studied in 10 patients with biopsy-proven prostate cancer. The studies performed included static investigations and dynamic investigations of the prostate vasculature. All studies were double performed. The assessment of reproducibility was done objectively using a computer program and, subjectively, by visual assessment. The results indicate high reproducibility of static contrast investigations, for both the objective and subjective assessment. The subjective assessment of the dynamic studies was also highly reproducible. The objective assessment of the dynamic contrast studies, however, was less reproducible, mainly due to motion artefact. We concluded that, especially static 3-D contrast-enhanced, power Doppler investigations of the prostate are highly reproducible.

Aged↗
PubMed1999

Setup reproducibility in radiation therapy for lung cancer: a comparison between T-bar and expanded foam immobilization devices.

PURPOSE: Physiologic and non-physiologic tumor motion complicates the use of tight margins in three-dimensional (3D) conformal radiotherapy. Setup reproducibility is an important non-physiologic cause of tumor motion. The objective of this study is to evaluate and compare patient setup reproducibility using the reusable T-bar and the disposable expanded foam immobilization device (EFID) in radiation therapy for lung cancer. METHODS AND MATERIALS: Two hundred forty-four portal films were taken from 16 prospectively accrued patients treated for lung cancer. Patients were treated with either a pair of anterior and posterior parallel opposing fields (POF), or a combination of POF and a three-field isocentric technique. Each patient was treated in a supine position using either the T-bar setup or EFID. Six patients were treated in both devices over their treatment courses. Field placement analysis was used to evaluate 3D setup reproducibility, by comparing positions of bony landmarks relative to the radiation field edges in digitized simulator and portal images. Anterior-posterior, lateral, and longitudinal displacements, as well as field rotations along coronal and sagittal planes were measured. Statistical analyses of variance were applied to the deviations among portal films of all patients and the subgroup treated with both immobilization methods. RESULTS: For the T-bar immobilization device, standard deviations of the setup reproducibility were 5.1, 3.7, and 5.1 mm in the anterior-posterior, lateral, and longitudinal dimensions, respectively. Rotations in the coronal plane and the sagittal plane were 0.9 degrees and 1.0 degrees, respectively. For the EFID, corresponding standard deviations of set up reproducibility were 3.6 mm, 5.3 mm, 5.4 mm, 0.7 degrees and 1.4 degrees, respectively. There was no statistically significant difference (p = 0.22) in the 3D setup reproducibility between T-bar and EFID. Subgroup analysis for the patients who were treated with both immobilization devices did not reveal a difference either. There was no consistent systematic error from simulator to treatment unit identified for either immobilization device. CONCLUSION: Although the optimal immobilization technique and patient positioning for thoracic radiotherapy have yet to be determined, this study indicates that T-bar is comparable with EFID in its setup reproducibility. In view of the inherent advantages of T-bar, it has become a standard immobilization device at our institution. The observed range of displacements in field positioning with either immobilization device implies that one cm (two standard deviations [SD] of setup error) will be a more appropriate margin to allow for setup variability in radiation therapy for lung cancer.

Equipment Design↗
PubMed1998

Ultrasound biomicroscopy. II. Intraobserver and interobserver reproducibility of measurements.

PURPOSE: To evaluate intraobserver and interobserver reproducibility of measurements in images obtained by the 50 MHz Humphrey Ultrasound Biomicroscope. METHODS: The first stored image of central cornea, central anterior chamber, and angle structures obtained at 50 examinations were measured twice by three observers. Nine different parameters were measured in angle images and two in images of central cornea and anterior chamber. Intraobserver reproducibility was assessed by calculating the coefficient of variation and interobserver reproducibility by a two-ways ANOVA. RESULTS: Intraobserver reproducibility was high for all measurements of central cornea thickness and anterior chamber depth with a coefficient of variation (%) < or = 3.8%. In angle images the intraobserver reproducibility of measurements was often lower (coefficient of variation (%) 1.3-52.6%). The lower reproducibility was most noticeable in measurements involving the less defined structures. Interobserver reproducibility was poor. CONCLUSIONS: Comparison of measurements are best done of well defined structures and by only one observer.

Anterior Chamber↗
PubMed2000

Reliability of computerized perimetric threshold tests as assessed by reliability indices and threshold reproducibility in patients with suspect and manifest glaucoma.

BACKGROUND: High reproducibility of test measurements is often considered an indication of high reliability of test results. The aim of the current study was to analyse the role of the traditional perimetric reliability indices, False Negative and False Positive responses, and Fixation Losses, as indicators of test reliability in comparison with threshold reproducibility in patients with suspect or manifest glaucoma. METHODS: Perimetry was performed in one eye in each of 76 patients. Each eye was tested twice within approximately one week using the Humphrey II 30-2 SITA STANDARD program. Frequencies of False Positive and False Negative answers, and rates of Fixation Losses were related to threshold reproducibility and to general field status as expressed by Mean Deviation from age-normal threshold values using stepwise multiple linear regression analysis. RESULTS: Substantial field loss was associated both with low threshold reproducibility (p<0.0001) and with increased frequency of False Negative answers (p=0.047). The traditional reliability indices contributed marginally compared to amount of field loss when predicting threshold reproducibility; the coefficient of determination decreased non-significantly from 0.37 to 0.33 when excluding the three reliability indices as explanatory variables from the regression model. Frequencies of False Positive answers and Fixation Losses showed no association to field status or to threshold reproducibility. CONCLUSION: Reliability of visual field test results in patients with glaucoma expressed as threshold reproducibility, can be predicted by amount of field loss alone, and traditional patient reliability indices contribute surprisingly little in this regard.

Aged↗
PubMed1997

Reproducibility of a food frequency questionnaire used in the New York University Women's Health Study: effect of self-selection by study subjects.

OBJECTIVE: The aim of the study was to investigate the reproducibility of a food frequency questionnaire (FFQ) used in a cohort of 14,290 women enrolled in the NYU Women's Health Study. DESIGN: A subset of 474 cohort subjects who completed the dietary questionnaire at baseline (FFQ-1) were approached again on the occasion of a second visit to the mammography study centre and asked to complete the questionnaire a second time (FFQ-2) two to four years after FFQ-1. Two to three months later the questionnaire was mailed to the subjects, and they were asked to complete it a third time (FFQ-3). SETTING: A breast cancer screening clinic. SUBJECTS: Of the 474 subjects selected, 100% completed the second questionnaire while only 56% completed and mailed back FFQ-3. This made it possible to compare the long-term reproducibility of dietary intake measurements and baseline dietary habits between the two groups of subjects 'respondents', who agreed to complete the questionnaire a third time, and 'non-respondents', who did not. RESULTS: Among respondents (56% of study subjects), energy-adjusted correlation coefficients for short-term reproducibility between FFQ-2 and FFQ-3 ranged from 0.50-0.64 for nutrients, and from 0.44-0.67 for foods. The long-term reproducibility was lower, ranging from 0.36-0.53 for nutrients, and from 0.31-0.48 for specific food groups. Among those who did not respond to FFQ-3, crude correlations for long-term reproducibility, unadjusted for energy intake, were generally lower than among respondents. Nevertheless, after adjustment for energy intake, correlations for long-term reproducibility (FFQ-2 to FFQ-1) were of similar magnitude in both groups. In addition, 'non-respondents' reported lower intake of fruit and vegetables and higher intake of meat. CONCLUSIONS: The results of this study suggest that subjects who volunteer to participate in substudies on the validity or reproducibility of dietary questionnaire measurements may tend to provide more accurate responses to the questionnaire. The phenomenon seems related more to accuracy of reporting of absolute intake levels than of the relative composition of diet, self-selection may be associated with differences in dietary habits.

Adult↗
PubMed2000

Factors affecting reproducibility of dietary reports using food frequency questionnaires.

OBJECTIVE: To study the reproducibility of a food frequency questionnaire used to assess past dietary habits. DESIGN: Repeated retrospective assessment of dietary habits of a population sample. SETTING: Uppsala-Orebro Health Care Region of Sweden. SUBJECTS: One-hundred and four subjects participating as control subjects in a case-control study on thyroid cancer. INTERVENTIONS: Between spring 1993 and spring 1994 a case-control study was conducted in the study area, in order to investigate risk factors for thyroid cancer-diet among others. The study subjects reported their consumption of selected foods with reference 1-5 y before, as well as dietary changes that occurred from adolescence to adult age. One year later 197 control persons were invited to provide a second report of the same food items. Of the invited subjects 104 agreed to participate. RESULTS: The median Spearman rank correlation coefficient between the first and second assessment was 0.58 for food consumption and 0. 56 for nutrients intake. Correlation between the two assessments varied greatly between food items, ranging from -0.03 to 0.83. The correlation was positively related to the frequency and negatively related to the skewness of consumption. The recall of dietary changes from adolescence had a median correlation coefficient of 0. 38 (range 0.19-0.69). There were hints of a higher reproducibility of dietary reports among men and among highly educated subjects (more than 11 y of education), but these differences were statistically significant only for recall of adolescent diet. Reproducibility of nutrients intake was also significantly higher among men than among women, as well as among subjects older than 45 y. CONCLUSIONS: The reproducibility of dietary reports was satisfactory. Among factors affecting reproducibility, frequency and homogeneity of consumption in the source population are presumably the most important. Age, sex and education modify the inter-subject reproducibility of past diet. Based on reproducibility of a semi-quantitative index, the recall of adolescent diet probably has a low validity. European Journal of Clinical Nutrition (2000) 54, 658-664.

Adult↗
PubMed2004

Short- and long-term reproducibility of autonomic measures in supine and standing positions.

Autonomic nervous tests and heart rate variability (HRV) have been used to assess cardiac autonomic function and to evaluate long-term prognosis. The aim of this study was to evaluate the short- and long-term reproducibility of HRV parameters and autonomic nervous tests according to body position (supine or standing). The study group consisted of 26 healthy subjects. Autonomic nervous tests and HRV were performed twice during the day and the results were averaged. The protocol was then repeated 3 days after each examination and also after 6 and 24 months. Autonomic nervous tests included deep breathing, Valsalva manoeuvre and isometric muscle exercise (handgrip), as well as blood pressure and heart rate in response to standing. ECG recordings were taken for 10 min during spontaneous breathing for HRV analysis. We found that the reproducibility of some parameters of the autonomic nervous test were independent of body position [E/I ratio (heart rate response to deep breathing)], whereas other parameters were dependent on body position (Valsalva manoeuvre and blood pressure response to sustained handgrip). In addition, within-day measurements of those parameters varied from non-reproducible (Valsalva ratio, handgrip and blood pressure response to standing) to moderately reproducible [E/I ratio and 30/15 ratio (heart rate response to standing)]. Among the HRV parameters, we found that total power (TP), low (LF)- and high (HF)-frequency were reproducible not only for measurements made within the same day, but also during short- and long-term observations, and only the LF/HF ratio was dependent on body position. We conclude that only a few autonomic nervous tests are reproducible in the short- and long-term. Because HRV parameters obtained during spontaneous respiration showed high reproducibility for measurements made within the same day as well as in the short- and long-term, they should be used instead of autonomic nervous tests when long-term observations are carried out in a healthy population.

Adult↗
PubMed1998

The reproducibility of symptoms during a submaximal exercise test in chronic heart failure.

AIMS: The aim of this study was to evaluate the use of a submaximal test with a symptom limited endpoint and to measure the reproducibility of symptoms in patients with CHF. METHODS: Ten patients with chronic heart failure were studied. Based on two maximal treadmill tests an individual protocol using a constant work rate at a submaximal intensity was derived. The projected maximum treadmill time for the constant workrate was between 8 and 17 min. Tests were carried out 1, 2, 4 and 6 weeks after the maximum tests. Every 2.5 min during the submaximal test patients recorded their symptoms of breathlessness and fatigue using computer automated visual analogue (VAS) and Borg CR10 scales. The measure of reproducibility used was the proportion of total variability explained by the between subject variability. RESULTS: Using the VAS scale, general fatigue was reasonably reproducible ranging from 77-86%. For VAS breathlessness reproducibility ranged from 66% to 83%. Reproducibility for breathlessness and fatigue for the Borg CR10 scale was much lower than the VAS scale. Reproducibility for the treadmill times was 51% but increased to 76% if one test of one subject was excluded. CONCLUSIONS: The use of the VAS during submaximal exercise offers a useful means of evaluating symptoms in CHF and potentially their response to treatment. These findings show that individual submaximal protocols can be easily prescribed for CHF patients. Using such an approach, clinically desirable tests lasting around 12 min can be developed. These tests are reasonably reproducible and may provide a useful means of assessing patient disability and the impact of treatment.

Aged↗
PubMed1999

Reproducibility of abnormal heart rate variability indices: the case of hypertensive sleep apnoea syndrome.

Before heart rate variability can be used as an investigational tool in the clinical setting, its reproducibility must be known. We studied heart rate variability four times during 44 weeks in 15 hypertensive patients with sleep apnoea syndrome. Time and frequency domain analytical approaches were used during the spontaneous and controlled breathing tests, orthostatic manoeuvre and the cold pressor test. Alterations in resting heart rate were taken into account using the coefficient of component variance. In general, the response of heart rate variability was abnormal and variability was reduced in the hypertensive patients with sleep apnoea syndrome compared with reference data. Time domain measures of heart rate variability demonstrated generally better reproducibility over four recordings than frequency domain measures in these hypertensive patients with sleep apnoea syndrome. On the other hand, the reproducibility of frequency domain measures depended on the specific conditions: during orthostatic manoeuvre and cold pressor test the best reproducibility was found using normalized units. In the reference data set, there were no significant differences between the two heart rate variability recordings during any of the autonomic nervous function tests. In this follow-up study we found that simple procedures such as the controlled breathing test show good reproducibility. More complex tests such as the orthostatic manoeuvre require special attention in order to obtain acceptable reproducibility of heart rate variability measurements. Quantitatively minor changes in the variability indices when the overall variability is reduced exert major effects on the results. Therefore we suggest that reproducibility data obtained in healthy volunteers are not valid for the interpretation of data in patients with damaged cardiovascular autonomic control.

Adult↗
PubMed2005

Long-term reproducibility analysis of fMRI using hand motor task.

This article reports test-retest reproducibility of functional MRI (fMRI) measurement on brain activation elicited by auditory-cued sequential finger tapping. Eight right-handed volunteers participated in nine fMRI sessions, approximately eight weeks apart, for the duration of more than a year. The first scan session was repeated within a day to examine the intra-session reproducibility. The frequency of activation for neural substrates relevant to the task was constructed across the subjects and sessions. The spatial reproducibility was measured as the ratio of the size of the volume as well as its overlaps with respect to the first scan session from regions-of-interest in the selected motor circuitry. Consistent activation patterns between sessions and across subjects were observed in the sensorimotor areas such as the left primary, supplementary, and premotor areas, as well as in the right cerebellar areas without evidence of session-dependent trends. Quantitative analysis showed that the reproducibility measures varied within the range obtained from studies on fMRI reproducibility covering much shorter terms. Intra-session fMRI scans yielded slightly better reproducibility measures compared to the results obtained from other scan sessions. The findings suggest that the reproducible fMRI measurement can be obtained for long-term monitoring of brain function.

Acoustic Stimulation↗
PubMed2005

Interstudy reproducibility of quantitative perfusion cardiovascular magnetic resonance.

PURPOSE: To determine the interstudy reproducibility of quantitative first-pass perfusion cardiovascular magnetic resonance with comparison of 2 previously described analysis techniques. There is no published data on the interstudy reproducibility of perfusion cardiovascular magnetic resonance which can be used to determine the significance of longitudinal changes in myocardial perfusion after pharmacologic or therapeutic interventions with defined sample sizes. METHODS: Sixteen subjects (7 normal volunteers, 9 patients with coronary artery disease) had rest and adenosine stress perfusion cardiovascular magnetic resonance studies on two separate visits. A short axis slice was studied on each visit using a fast low-angle shot sequence. The global and regional myocardial perfusion reserve indices were calculated using 2 methods: model based constrained deconvolution with the Fermi function, and normalized upslopes. Reproducibility was defined as the standard deviation of the measurement differences, divided by the mean (coefficient of variation). RESULTS: The reproducibility of global myocardial perfusion reserve indices was 21% in normal volunteers, which was similar to that in patients with coronary artery disease (CAD) (23%, p = .88). The reproducibility of regional myocardial perfusion reserve indices was 28% (p = .45 vs. global analysis). The reproducibility of global MPRi was superior with Fermi deconvolution compared with normalized upslopes (21% vs. 41%, p = .02). CONCLUSION: At this stage of clinical development, the reproducibility of quantitative perfusion cardiovascular magnetic resonance is good, and superior using Fermi deconvolution in preference to upslope analysis.

Adenosine↗
PubMed1998

On the influence of sample size on the prognostic accuracy and reproducibility of renal transplant biopsy.

INTRODUCTION: The minimal specimen size necessary for accurate interpretation of a renal biopsy has not been identified. We attempted such a determination by three different analyses of a collection of biopsies performed in renal transplants. METHODS: First, we studied the influence of three lesions (glomerulosclerosis, arteriolar hyalinosis, interstitial fibrosis/tubular atrophy) in 199 baseline biopsies, obtained at time of transplantation, on transplant outcome. Secondly, we compared the results from the three lesions in baseline biopsy with those from 114 subsequent core biopsies in the same patients. Thirdly, we compared the two baseline biopsies obtained in 118 paired kidneys in cadaver transplantation where both kidneys were used. RESULTS: For statistically significant prediction of outcome from glomerulosclerosis, we found that a specimen containing at least 25 glomeruli was needed in the baseline biopsy. Arteriolar hyalinosis predicted outcome independent of sample size, but became less important than percentage glomerulosclerosis in predicting outcome if only samples containing more than 25 glomeruli were considered. Interstitial fibrosis/tubular atrophy did not predict the outcome of a kidney, independent of sample size. When comparing baseline with subsequent core biopsies, or with paired baseline biopsies, at least 14 glomeruli were necessary to allow even moderate reproducibility of glomerulosclerosis (Cohen's kappa > 0.25) and to allow statistical significance (P < 0.05). The reproducibility of arteriolar hyalinosis was not dependent on sample size but was reproducible in 80% of paired baseline biopsies, and in 67% of the comparison of the baseline with core biopsy. Both precision and significance was lost if sample numbers were reduced by including only larger samples. There was no reproducibility in any study of interstitial fibrosis/tubular atrophy when comparing either baseline with subsequent biopsy, or paired baseline biopsies. SUMMARY: Much larger biopsy samples are necessary than has generally been assumed in order for glomerulosclerosis rates to be reproducible or predictive of outcome. Arteriolar hyalinosis is prognostically important and shows good reproducibility independent of sample size. Interstitial fibrosis/tubular atrophy appear useless as predictors, being of no prognostic importance and lacking reproducibility. Our finding clarifies some of the discrepancies found by different investigators regarding the importance of renal biopsy in predicting prognosis. Preliminary, our data indicate that samples containing fewer than 25 glomeruli are unreliable in determining outcome based on glomerulosclerosis. The importance of our findings which are based only on chronic lesions, with respect to acute changes, is unknown.

Adolescent↗
PubMed1992

Thermodilution right ventricular ejection fraction measurement reproducibility--a study in patients undergoing coronary artery bypass graft surgery.

OBJECTIVE: To assess the effects of heart rate, right ventricular systolic performance (ejection fraction), chamber dimensions, and flow rate (cardiac index) on the reproducibility of algorithm-derived triplicate thermodilution right ventricular ejection fraction measurements. DESIGN: Prospective study; combined hemodynamic and echocardiographic clinical evaluation. SETTING: Operating room in a university hospital. PATIENTS: Twenty-one coronary artery bypass graft patients. MEASUREMENTS AND MAIN RESULTS: The right atrial delivery site was positioned by analysis of transduced pressure waveform and echocardiographic imaging of tracer agitated saline cavitations. Measurement reproducibility was quantified by determining the variation (standard deviation) within 101 triplicate thermodilution measurement sets. There was no significant relationship between measurement reproducibility and estimates of right atrial area (21.6 +/- 6.9 cm2), diameter (5.1 +/- 0.8 cm) and supero-inferior length (5.1 +/- 0.9 cm) and right ventricular maximal minor axis diastolic diameter (4.21 +/- 1.05 cm). Reproducibility was also unrelated to right ventricular end-diastolic volume index (97.9 +/- 32.7 mL/m2) and cardiac index (2.9 +/- 0.9 L/min/m2). Measurement reproducibility was directly related to mean right ventricular ejection fraction (0.39 +/- 0.14) and inversely related to heart rate (80.8 +/- 18.6 beats/min) (p < .01 and < .001, respectively). CONCLUSIONS: Thermodilution-derived right ventricular ejection fraction measurement reproducibility was unrelated to estimates of right atrial and ventricular dimensions and cardiac index. Measurement reproducibility was a direct function of right ventricular systolic performance and an indirect function of heart rate. Measurement should be interpreted with these constraints in mind.

Adult↗
PubMed2000

Ultrasound assessment of atherosclerotic vessel wall changes: reproducibility of intima-media thickness measurements in carotid and femoral arteries.

RATIONALE AND OBJECTIVES: Ultrasonography is widely used in cardiovascular research to quantify early atherosclerotic vessel wall changes. In this article, we examined the short- and long-term reproducibility of this technique in the common carotid artery, carotid bifurcation, common femoral artery, and superficial femoral artery. Furthermore, we assessed the effect of progressed atherosclerosis on reproducibility. METHODS: Repeated ultrasound examinations were performed by one observer on 15 healthy individuals and 18 patients suffering from coronary heart disease. Intima-media thickness was determined by B-mode ultrasonography. The examinations were repeated by the same observer after a short time interval (short-term) and after a few weeks (long-term) and expressed as the mean difference between the measurements and the coefficient of variation (CV). RESULTS: The reproducibility of the intima-media thickness determination turned out to be best in the common carotid artery and the superficial femoral artery when performed in healthy controls (CV 5.6% and 5.5%, respectively). Reproducibility was less in patients with clinical atherosclerosis; this especially affected the reliability of the superficial femoral artery measurement (CV in healthy controls was 5.5%; in coronary heart disease patients, 17.5 %). The reliability of the intima-media thickness measurements in the common carotid artery (CV in healthy controls was 5.6%; in coronary heart disease patients, 9.5%) proved to be least affected by progressed atherosclerosis. A longer time interval between measurements did not affect the reproducibility of intima-media thickness measurements in healthy controls, whereas in the patients it led to some decrease of reproducibility and to a major decrease in reproducibility of the superficial femoral artery measurements (CV changed from 12.7% to 17.5%). CONCLUSIONS: Ultrasonography is a reliable and accurate technique to determine intima-media thickness in superficial arteries. In studies in which the intima-media thickness determination is used as a marker for generalized and coronary atherosclerosis, the common carotid artery should always be included, whereas the benefit of inclusion of other arteries depends on age and the expected extent of atherosclerosis in the individuals studied.

Adult↗
PubMed2005

Reproducibility of home and ambulatory blood pressure in children and adolescents.

OBJECTIVE: To evaluate the reproducibility of blood pressure measured at home (HBP) in comparison with ambulatory (ABP) and clinic blood pressure (CBP) in children and adolescents. PARTICIPANTS AND METHODS: Individuals aged 8-17 years who had been referred for elevated CBP were included. CBP was measured at two visits, HBP on 5 days and ABP for 24 h. A second session including all the above measurements was performed after 8 weeks. The reproducibility of CBP (second visit of each session), HBP (average of days 2-5 of each session) and ABP (average 24-h, awake and asleep) was quantified using test-retest correlations coefficients (r) and the standard deviation of differences (SDD) between repeated measurements. RESULTS: Sixteen individuals were included [mean age 13.3+/-2.9 (SD)] years, range 8-17, nine boys]. According to Task Force CBP criteria, eight were classified as hypertensives, three as high normal and five as normotensives. The reproducibility of HBP (systolic/diastolic r, 0.74/0.82, SDD 7.0/4.3) was superior to that of CBP (r, 0.63/0.80, SDD 10.4/6.3). However, ABP appeared to provide the most reproducible values (r, 0.87/0.84, SDD 5.5/4.3 for 24-h ABP; r, 0.85/0.76, SDD 5.9/5.0 for awake; r, 0.76/0.79, SDD 7.0/5.0 for asleep ABP). Aspects of the diurnal ABP variation were poorly reproducible (r, 0.62/0.14, SDD 6.8/5.5 for awake-asleep ABP difference; r, 0.55/0.26, SDD 0.07/0.11 for awake : asleep ratio). CONCLUSION: These data suggest that in children and adolescents home blood pressure measurements are more reproducible than clinic measurements. However, 24-h ambulatory monitoring appears to provide the most reproducible blood pressure values.

Adolescent↗
PubMed2006

Reproducibility of jaw movements in patients with craniomandibular disorders.

It has never been investigated, if mandibular movements of patients with craniomandibular disorders (CMD) result in a lower reproducibility of dynamic functional parameters which are used for the individual articulator setting. The aim of the present study was to compare the reproducibility of electronically registered functional parameters in patients with CMD and in a control group. Dynamic functional parameters were recorded in 30 patients and 30 volunteers with a computerized ultrasound system (ARCUSdigma). The whole registration was performed three times during one session and three times at a second session 1 week later. The horizontal condylar inclination in the patient group gave a standard deviation of 2.17 degrees +/- 0.95 degrees , indicating poorer reproducibility than in the volunteer group, for which the standard deviation was 1.37 degrees +/- 0.42 degrees . The reproducibility of measurements of the Bennett angle was also poorer in the patient group than in the volunteer group, with standard deviations of 1.70 degrees +/- 0.62 degrees and 1.22 degrees +/- 0.40 degrees , respectively. The standard deviations calculated for determination of incisal inclination during laterotrusion was 3.02 degrees +/- 1.49 degrees for patients and 2.30 degrees +/- 1.17 degrees for volunteers. The standard deviations for incisal inclination during protrusion was 2.02 degrees +/- 0.95 degrees for patients and 2.06 degrees +/- 1.82 degrees for volunteers. The reproducibility of measurement of horizontal condylar inclination, Bennett angle and incisal inclination during laterotrusion therefore showed significantly lower reproducibility in the patient group than in the volunteer group (P < 0.05). The overall reproducibility of the measurements was nevertheless good in both groups, with standard deviations under 3.1 degrees , so that an individual setting of an articulator seems useful even in patients with CMD.

Craniomandibular Disorders↗
PubMed2004

Day-to-day reproducibility of anorectal sensorimotor assessments in healthy subjects.

The reproducibility of tests widely utilized to assess anorectal sensorimotor functions is not well established. Our aims were to assess the intra-individual day-to-day reproducibility of these parameters in healthy subjects. Anal sphincter pressures were assessed by perfusion manometry on two separate days in 19 healthy subjects. Rectal pressure-volume (p-v) curves and sensory thresholds were assessed in 12/19 subjects by inflating a highly compliant polyethylene balloon from 0 to 32 mmHg in 4 mmHg steps. Subjects also rated intensity of perception by visual analogue scale (VAS) during phasic distentions 8, 16 and 24 mmHg above operating pressure, in randomized sequence. Resting and squeeze anal pressures and rectal compliance were highly reproducible (r(s) > or = 0.7) in the same subject on separate days. Pressure thresholds for urgency appeared less reproducible than thresholds for initial perception and the desire to defecate. VAS scores were highly reproducible only during the 24-mmHg distention. Thus, anal pressures and rectal compliance are highly reproducible within healthy subjects on separate days, while sensory thresholds are reproducible to a variable degree, dependent on the intensity of stimulation and the perception being assessed.

Adult↗