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At least 19 recordsLinked to original sources
PubMed2002

The associated reaction rating scale: a clinical tool to measure associated reactions in the hemiplegic upper limb.

OBJECTIVE: To determine what items should be included in a clinical assessment tool developed to measure associated reactions in the hemiplegic upper limb and to assess the reliability of the resultant measure. DESIGN: Development through a structured consultative process using focus group methodology. Evaluation of inter- and intra-rater reliability between two independent observers. SUBJECTS: Nineteen consecutive hemiplegic patients admitted to Northwick Park Hospital for rehabilitation following stroke. METHODS: Focus groups were conducted in two centres, comprising physiotherapists experienced in the clinical management of brain injury. The groups identified four key characteristics related to severity of associated reactions, which became the items of the rating scale. Evaluation of inter- and intra-rater reliability was undertaken by comparison of agreement between ratings of associated reactions occurring during a single standardized task (sit-to-stand), by two senior physiotherapists in 19 subjects. RESULTS: There were good correlations between the two raters in total (rho 0.89 p < 0.005) and modal scores (rho 0.88 p < 0.005). Reliability testing of each item revealed moderate to very good inter-rater agreement (weighted kappa values 0.43-0.85) and good to very good intra-rater agreement (weighted kappa values 0.61-0.87). A slight tendency for one rater to score more severely than the other only reached significance for one item (excursion). Overall (modal) severity scores showed a good level of agreement (kappa 0.76-0.81) both between and within raters. CONCLUSION: Items to be included in a clinical assessment tool to measure associated reactions in the hemiplegic upper limb were determined. Reliability of the resultant measure was found to be encouraging. These results however apply only to observations made during a specific standardized task (sit-to-stand) and further study of sensitivity to change and reproducibility in different tasks is required before the findings can be extrapolated into routine practice.

Adult↗
PubMed2005

Evaluation of statistical association measures for the automatic signal generation in pharmacovigilance.

Pharmacovigilance aims at detecting the adverse effects of marketed drugs. It is generally based on the spontaneous reporting of events thought to be the adverse effects of drugs. Spontaneous Reporting Systems (SRSs) supply huge databases that pharmacovigilance experts cannot exhaustively exploit without data mining tools. Data mining methods; i.e., statistical association measures in conjunction with signal generation criteria, have been proposed in the literature but there is no consensus regarding their applicability and efficiency, especially since such methods are difficult to evaluate on the basis of actual data. The objective of this paper is to evaluate association measures on simulated datasets obtained with SRS modeling. We compared association measures using the percentage of false positive signals among a given number of the most highly ranked drug-event combinations according to the values of the association measures. By considering 150 drugs and 100 adverse events, these percentages of false positives, among the 500 most highly ranked drug-event couples, vary from 1.1% to 53.4% (averages over 1000 simulated datasets). As the measures led to very different results, we could identify which measures appeared to be the most relevant for pharmacovigilance.

Adverse Drug Reaction Reporting Systems↗
PubMed1988

[Visual behavior in conversational dyads: comparison between total eye contact measure and localized gaze pattern measure associated with turn of talk].

The present paper investigated visual interaction in conversational dyads by using a larger range of gaze pattern measures associated with conversation than the total eye contact measure. Specifically, it aimed to demonstrate the effectiveness of the localized gaze pattern measure, which was scored for each subject by summing up gaze patterns for 3 s immediately prior to and following the end of the interviewer's utterance over three occasions. Twenty female students were interviewed by one male student for about 10 min. The interview topics were "fashion" for the first 5 min and "sex" for the remaining 5 min. (1) The frequency of a subject's gaze and eye contact was significantly greater in the "fashion" topic than in the "sex" topic, but the total amount and average length of both measures were not significantly different between the topics. (2) Immediately after the end of the interviewer's utterance subjects' gaze decreased, with significantly lesser localized gaze in the "sex" topic than in the "fashion" topic. It could thus be said that the localized gaze measure was more sensitive than the total eye contact measure.

Adult↗
PubMed2000

Periodontal-type measurements associated with hydroxyapatite-coated and non-HA-coated implants: uncovering to 36 months.

BACKGROUND: While the use of hydroxyapatite (HA)-coated endosseous dental implants has gained in popularity over the past 10 years, the short-term and long-term predictability and indications for their use remain highly controversial. Some reports suggest that the HA coating may separate from the substructure, undergo dissolution in tissue fluids, and/or contribute to rapid osseous breakdown around the implant. Other reports, however, relate favorable responses to HA-coated implants, which include rapid bone adaptation to the HA, greater stability at uncovering, and increased coronal bone growth. These contradictions may be related to differences in chemical composition of the HA on the implant surface. Most clinicians and researchers may agree that long-term, independent, scientific clinical studies are needed to compare HA-coated and non-HA-coated (titanium-alloy and CP-titanium) implants under the same conditions. Concerns appear in the literature that HA-coated implants experience greater breakdown because they are more susceptible to bacterial colonization due to their roughness and hydrophilicity. Some studies suggest that specific putative periodontal pathogens may adhere to the HA, thereby predisposing the implant to greater peri-implantitis than that experienced by non-HA implants. METHODS: A total of 32 clinical research centers, located in various geographic regions of the United States, were selected to participate in a comprehensive clinical study. More than 2,900 HA-coated and non-HA implants were randomized as to location within one of three jaw regions--maxillary anterior, mandibular anterior, and mandibular posterior--and followed for 36 months. It can be assumed that in each of these jaw regions, the conditions associated with both implant surface types would be similar enough to permit meaningful comparisons of periodontal-type measurements that have not previously been reported. Periodontal-type measurements (gingiva, plaque, suppuration, and calculus indices; probing depth; attachment levels; recession; and keratinized tissue width) for each aspect of each implant (mesial, facial, distal, and lingual) were recorded at 3, 6, 9, 12, 18, 24, and 36 months following implant uncovering. The implant was considered the experimental unit for analysis using generalized estimating equation and repeated measure methods. Data for the four aspects of each implant, as well as measurements over time, were all clustered in the unit of analysis. RESULTS: The percentages of implants with zeros recorded for the indices was remarkably similar for both HA-coated and non-HA implants. While statistically significant differences were found for some of the measurements associated with HA-coated and non-HA implants under certain conditions, these differences were too small to be considered clinically significant. CONCLUSIONS: Overall, there was no clinically significant difference between the periodontal-type measurements for HA-coated and non-HA-coated implants followed for a period from 3 through 36 months. The concerns about HA-coated implants being associated with adverse periodontal responses for the HA chemical composition included in this study appear to be unfounded for a period of clinical performance up to 36 months.

Adult↗
PubMed1983

A comparison of various strength of association measures commonly used in gerontological research.

An increased usage of measures of strength of association or effect size (ES) has been noted in the gerontological literature. Potential confusion could be generated by the fact that different researchers have reported different measures of ES from study to study. This paper involves a comparison of six ES measures commonly used by gerontological researchers as these measures relate to one another in both the analysis of variance and multiple regression models. Three other issues involving ES measures are discussed: (1) the ES of a contrast; (2) orthogonal and nonorthogonal designs; (3) partial Ess.

Age Factors↗
PubMed2006

A prospective study of anthropometric and clinical measurements associated with insulin resistance syndrome and colorectal cancer in male smokers.

Type 2 diabetes mellitus shares risk factors for and has shown a positive association with colorectal cancer. Anthropometric measures (height, weight, and body mass index (weight (kg)/height (m)(2)) and metabolic abnormalities associated with insulin resistance syndrome (IRS) (abnormalities in measured blood pressure, high density lipoprotein (HDL) cholesterol, and total cholesterol) were prospectively evaluated for associations with incident colon (n = 227), rectal (n = 183), and colorectal (n = 410) cancers diagnosed between 1985 and 2002 in 28,983 Finnish male smokers from the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. Cox proportional hazards models were used to calculate hazard ratios and 95% confidence intervals. In comparison with the lowest quintile, the highest quintile of body mass index was significantly associated with colorectal cancer (hazard ratio (HR) = 1.70, 95% confidence interval (CI): 1.01, 2.85; p-trend = 0.01), particularly colon cancer. Subjects with a cluster of three IRS-related conditions (hypertension, body mass index >/=25 kg/m(2), and HDL cholesterol level <40 mg/dl (<1.55 mmol/liter)), compared with those with fewer conditions, had a significantly increased risk of colorectal cancer (HR = 1.40, 95% CI: 1.12, 1.74), particularly colon cancer (HR = 1.58, 95% CI: 1.18, 2.10), but not rectal cancer. These results support the hypothesis that the significant association observed between IRS-defining metabolic abnormalities and colorectal cancer is determined primarily by adiposity.

Adiposity↗
PubMed2006

Is the use of ergonomic measures associated with behavioural change phases?

The aim of this study was to test the hypothesis that the absolute number of completed behavioural change phases (ABP) and the sequentially ordered number of completed behavioural change phases (SBP) are positively associated with the use of ergonomic measures by two groups of stakeholders in bricklaying companies (employers/planners, foremen/bricklayers). The measures, consisting of trestles, bricklaying scaffolds, mast-climbing work platforms and cranes, reduce the physical work demands made upon bricklayers and bricklayers' assistants. Structured interviews were conducted with stakeholders of 27 companies. Ordinal regression of behavioural change phases on the use of ergonomic measures showed a significant increase in both ABP and SBP in relation to increased use of three of the four ergonomic measures (i.e. trestles, bricklaying scaffolds, mast-climbing work platforms) by employers/planners and increased use of one ergonomic measure (i.e. trestles) by foremen/bricklayers. In conclusion, the positive and significant associations between the completed behavioural change phases (ABP and SBP) and use of ergonomic measures differ for the stakeholder groups and between the ergonomic measures. The data suggest that there is a higher chance of increasing the use of ergonomic measures by means of a higher ABP than a higher SBP. It is recommended for activities to be carried out-primarily by employers/planners-to facilitate as many behavioural change phases as possible in order to stimulate actual use of ergonomic measures at worksites.

Adult↗
PubMed1995

Autonomic measures associated with chemotherapy-related nausea: techniques and issues.

Advances in antiemetic therapy for cancer patients have been hindered by a lack of understanding of the physiological mechanisms associated with nausea and their corresponding measurement techniques. Here we review conceptual and methodological issues involved in developing an autonomic frame of reference for nausea and outline two strategies for assessing autonomic function. A primarily research-oriented strategy uses heart rate, blood volume pulse, pallor, and skin temperature to assess autonomic activity and reactivity over 24 hr. Peak values of these measures relative to time of emesis, heart rate spectral analyses of autonomic activity, and analyses of the standard deviation of successive differences of beat-to-beat intervals were all associated with subsequent nausea. A primarily clinically oriented strategy assesses normal and abnormal results on eight common bedside clinical tests of autonomic function. The total number of abnormal tests was associated with subsequent nausea. A better understanding of chemotherapy side effect mechanisms is likely to result in less polypharmacy and more effective individualized treatment for cancer patients.

Arrhythmia, Sinus↗
PubMed1991

Auditory nerve spatial encoding of high-frequency pure tones: population response profiles derived from d' measure associated with nearby places along the cochlea.

We examined a measure of discriminability in auditory nerve (AN) population responses that may underlie behavioral frequency discrimination of high-frequency pure tones in the cat. Population responses of high- (greater than = 15 spikes/s) and low- (less than 15 spikes/s) spontaneous rate (SR) AN fibers in unanesthetized decerebrate cats to 5 kHz pure tones were measured in the form of mean, mu, and standard deviation, sigma, of spike counts for 0.2 s tone bursts. The AN responses were analyzed in terms of a d'e(x, delta x) associated with adjoining cochlear places as defined in the manner of signal detection theory. We also examined sigma d'e(x, delta x), a spatial summation of the discriminability measure. The major findings are: (1) the d'e(x, delta x) function conveys information about 5 kHz pure tone frequency over a region of +/- 0.5 to 1.0 octave, or +/- 1.67 to 3.33 mm, around the characteristic place (CP), with the region being narrower at lower stimulus levels; (2) at 30 dB SPL, the integrated d'e(x, delta x) discriminability scores are similar for the apical and basal regions surrounding the CP whereas, at 70 dB SPL, the scores are higher for the apical region than for the basal region; and (3) at 50 and 70 dB SPL, the integrated d'e(x, delta x) discriminability scores of low-SR fibers were higher than those of high-SR fibers although, at 30 dB SPL, the latter were higher than the former. By using the cat cochlear frequency-place relationship and the inner hair cell (IHC) spacing, we interpret that the cat's frequency difference limen, delta f/f = 0.0088 at 4 kHz [Elliott et al., 1960, J. Acoust. Soc. Am. 32, 380-384], corresponds to a shift of cochlear excitation profile by 4.5 IHCs. From the present analysis of AN responses, we conclude that, for high-frequency pure tones, the d'e(x, delta x) code, an example of rate-place code, of frequency provides sufficient information to support the cat's behavioral frequency discrimination.

Acoustic Stimulation↗
PubMed2003

Alterations in random event measures associated with a healing practice.

OBJECTIVE: To determine whether alterations in random events, as measured by a Random event generator (REG), occur in association with a bioenergy healing practice. DESIGN AND SETTING: Two REGs were set up and run in parallel: one in a bioenergy healer's office and another at a local library as a control. Two multiday sets of data were collected in each setting. A third set was collected in which a reduced amount of attention was placed on the REG by the healer. REG excursions were calculated and compared for (1) overall days in the library and bioenergy healer's office, (2) healing and nonhealing phases in the healing office, and (3) overall excursions during high(sets 1 and 2) and low attention (set 3) by the healer. RESULTS: The library REG produced excursions outside the 95% confidence interval (CI) on 35 of 61 days (58%), and the REG in the healing practice 47 of 51 days (92%) (mean difference, 34%; 95% CI, 18% to 49%; chi(2) = 16.3, 1 df, p < 0.0005). In the healer's office, 0.6496 excursions per segment for healing phases and 0.6548 excursions per segment for nonhealing phases were shown (t = -1.3, 6794 df, p = 0.182). A comparison with chance expectation derived from Monte Carlo runs showed significantly less mean excursions per segment (t = -7.8, 36625 df, p < 0.0005) for healing phases and no difference in nonhealing phases (t = -0.16, 6309 df, p = 0.872). There was no significant difference in excursions between the high- and low-attention situations in the healing practice. CONCLUSIONS: In the presence of a healer, an REG produced greater than chance excursions more often than a control REG in a library setting. The healing and nonhealing phases demonstrated inconsistent results. REG deviations were not influenced by the amount of attention directed toward the machine.

Attitude to Health↗
PubMed1975

Bacterial bioluminescence: equilibrium association measurements, quantum yields, reaction kinetics, and overall reaction scheme.

The characteristics of the bioluminescence reactions with bacterial luciferase from two different cell types, Photobacterium fischeri and Beneckea harveyi, are reported. The reduced flavine mononucleotide (FMNH2)-luciferase association constant, directly measured by equilibrium dialysis and gel filtration is the same for both luciferases, 3 times 10(-4) Mminus1 at romm temperature, and is significantly different from the kinetic reciprocal Michaelis-Menten constant. The luciferase bioluminescence quantum yield for the highest activity preparations is the same as for the aldehyde. Rapid stopped-flow observations show that the oxidation of FMNH2 in the presence of sufficient luciferase to outcompete autoxidation, is bimodal. A long-lived intermediate, formed before reaction with aldehyde, has an activation energy for decay of 35 kcal mol-1, much greater than for the light reaction, 14 kcal mol-1. The ratio of bioluminescence quantum yields with respect to aldehyde and FMNH2 is independent of temperature, however, and also of aldehyde chain lenght longer than octanal, pH (6.5-8), and type of luciferase and its specific activity. Even when the aldehyde concentration limits the rate of the light reaction, the quantum yield of the long-lived intermediate is unchanged, and together these data mean that, under the optimal conditions chosen for quantum yield measurements, no dark side reactions effectively compete with the main reaction leading to light emission. A series of reactions involving one-electron steps and the sequential oxidation of two FMNH2 molecules is postulated for the formation of the long-lived intermediate.

Aldehydes↗
PubMed1998

Strength and pain measures associated with lateral epicondylitis bracing.

OBJECTIVE: To determine the effect of bracing on measures of pain-free grip strength and pain scores in individuals with unilateral lateral epicondylitis through a comparison of two elbow braces, a placebo brace, and a no-brace situation. DESIGN: Repeated-measures design in which the subjects acted as their own controls. SETTING: A clinical research laboratory at a hand and upper limb clinic. PATIENTS: Fifty individuals diagnosed by a physician with unilateral lateral epicondylitis, having symptoms for at least 3 weeks, were recruited from the community. INTERVENTIONS: The braces studied were the Count'R-Force Tennis Elbow Brace, the Body Glove Airprene Elbow Support, and a placebo brace that consisted of a modified DePuy Levy Clinic Patella Strap. MAIN OUTCOME MEASURES: Pain-free grip strength measured using an NK Biotechnical Corporation Hand Assessment System DIGIT-grip Device and pain scores measured on a visual numeric rating scale. RESULTS: No significant differences in pain-free grip strength or pain were observed between any of the test situations (p > .05). Pain during the test, however, was greater than pain before or after the test (p < .05). CONCLUSIONS: When tests were completed on one occasion with the brace on, no advantages of elbow bracing were detected. Whether bracing is effective when used as a treatment technique for an extended period of time should be addressed in future research.

Adult↗
PubMed1984

Mammary blood flow measurements associated with the development of bovine udder edema.

Mammary blood flow (MBF) and mammary plasma flow (MPF) were measured by an antipyrine absorption method in 8 cows affected with udder edema and 3 healthy (control) cows at least 2 weeks before parturition, at parturition, and 2 weeks after parturition. Cows with udder edema had a significant decrease in MBF at calving compared with the control cows (P less than or equal to 0.05), whereas there was no significant difference (P greater than 0.05) in MBF between affected and control groups 2 weeks before or 2 weeks after parturition. Cows with udder edema also had a decrease in MPF at parturition that was not statistically significant (P greater than 0.05) when compared with that in the control cows.

Animals↗
PubMed1985

Safety measures associated with the use of organophosphate insecticides in the Haitian malaria control programme.

A programme emphasizing intensive training, use of protective equipment and uniforms, daily supervision of safety measures at work, and weekly monitoring of blood cholinesterase levels by the tintometric method was instituted to prevent toxicity in Haitian malaria workers during spraying with the organophosphate insecticides fenitrothion and malathion. The programme functioned well, depressed cholinesterase activity (</= 50% of normal) being detected rapidly prior to the development of serious symptoms. Evidence of fenitrothion overexposure appeared in spraymen early in the first spray cycle, and was associated with faulty protective clothing and a failure to observe strictly the recommended safety measures at work. After these deficiencies were corrected, insecticide application continued without serious incidents or interruption of the programme. No serious reduction of cholinesterase activity was seen in a more limited study of spraymen using malathion. It is strongly recommended that similar training and monitoring programmes should be instituted whenever organophosphate pesticides are used as residual sprays for malaria control. This is particularly important in areas where the more toxic compound, fenitrothion, is to be used.

Cholinesterases↗
PubMed2006

Physiological measures associated with marathon running performance in high-level male and female homogeneous groups.

The study tested the hypothesis that physiological measurements can predict marathon running performance in a top-level homogeneous group of males and females. Ten male, performance: 2:12:04, coefficient of variation (CV)=2.33%, and 8 female marathon runners, performance: 2:34:53, CV=4.54%, performed an increment test on the treadmill (starting speed, 8 km.h-1; increments, 2 km.h-1; increment duration, 3 min to exhaustion). The heart rate (HR), VO2 and the lactate concentrations were measured at the end of each exercise level. During the recovery time, HR and lactate were measured. Furthermore, echocardiographic, anthropometric and haematologic measurements were made. The results of a stepwise multiple regression analysis using marathon time as the dependent variable yielded R2=0.983 for the male group and R2=0.984 for the female group. The model for the male group used the independent variables lactate value at 10 km.h-1, left ventricular telediastolic diameter (LVD) and lactate value at 22 km.h-1. The model for the female group used the independent variables subscapular skinfold, serum ferritin and sum of six skinfolds. Our study demonstrates that in males and females, physiological parameters can explain the variance in marathon time among elite homogeneous groups.

Adult↗
PubMed1997

Left, right, near or far wall common carotid intima-media thickness measurements: associations with cardiovascular disease and lower extremity arterial atherosclerosis.

We evaluated the differences in strength of the associations of prevalent cardiovascular disease and lower extremity arterial atherosclerosis to common carotid intima-media thickness, assessed by near wall measurements only, by far wall measurements only, and by the average of near and far wall measurements. The study was based on data from 1500 participants of the Rotterdam Study, a single-center-population-based prospective follow-up study among 7983 subjects, aged 55 years or over. Comparison of the strength of the associations of near wall intima-media thickness and of combined near and far wall intima-media thickness to cardiovascular disease and lower extremity arterial atherosclerosis revealed significantly stronger associations compared to associations observed for far wall intima-media thickness, in particular for stroke and lower extremity arterial disease. We conclude that near wall common carotid intima-media thickness measurement provides at least as good an indicator of atherosclerosis elsewhere and of cardiovascular risk as the far wall intima-media thickness measurement.

Arteriosclerosis↗
PubMed1999

Decay Index: a new carotid Doppler waveform measure associated with the Windkessel function of elastic arteries.

The Windkessel function of elastic arteries determines the postpeak contour of the internal carotid artery (ICA) Doppler waveform. To introduce an indicator for the function, the postpeak contour was reproduced by an exponential function, and the exponential coefficient was termed "Decay Index" (DI). DI obtained from 108 stenosis-free ICAs (55.2 +/- 15.8 y) was compared with surrogate measures for the Windkessel function (aortic pulse wave velocity, pulse pressure) and ICA peripheral resistance (resistive index, pulsatility index, systolic-to-diastolic ratio). DI was moderately correlated with the Windkessel and the resistance measures (r ranged 0.44-0.57). To clarify these intercorrelations, principal component analysis revealed two components. The first was loaded by the resistance measures (component load > or = 0.93) although the second was loaded by the Windkessel measures and DI (> or = 0.70), supporting an association between DI and the Windkessel function. Thus, DI is likely to represent an indicator for the Windkessel function.

Aorta↗