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At least 253 records · Page 14Linked to original sources

The Self-Appraisal Questionnaire: a self-report measure for predicting recidivism versus clinician-administered measures: a 5-year follow-up study.

In this study, the effectiveness of the Self-Appraisal Questionnaire (SAQ), a self-report measure for predicting release outcome, is examined as compared to clinician-administered and widely used risk prediction measures, over a 5-year period. The SAQ was administered along with four similar, but clinician-administered, measures to 91 federally sentenced Canadian male offenders prior to their release to the community. Follow-up data were collected for a 60-month period. Outcome criteria measures were violent and general recidivism. Results indicated that the SAQ is at least as effective as the four other measures in predicting postrelease outcome. The advantages of using the SAQ as a self-report measure as opposed to clinician-administered measures are discussed.

Adult↗

The problem with measuring patient perceptions of outcome with existing outcome measures in foot and ankle surgery.

Quality outcome measures are the cornerstone of clinical research. A review of outcome measures used in foot and ankle surgery research reveals that the issues of validity, reliability and responsiveness of outcome measures have not been addressed. Most reports in the literature have attempted to evaluate patient perceptions of outcome following foot surgery. Underlying the many difficulties with these outcome measures is a lack of understanding of what patients perceive to be important in terms of outcome. Consequently none of the existing outcome measures can claim to be valid measures of patient perceptions of outcome, as there has been no research uncovering these perceptions. In addition, measures of general health status and quality of life in relation to outcome of foot and ankle surgery have been largely ignored to date.

Ankle↗

How to measure sickness absence? Literature review and suggestion of five basic measures.

OBJECTIVE: To examine different sick-leave measures used in sickness absence research, and to suggest a systematic way of assessing sickness absence. METHODS: A review and analysis of five major studies on sick-leave performed 1983-1988 with an epidemiological approach. RESULTS: Terminology and measures used varied in the different studies reviewed. The choice of a certain measure was seldom discussed in relation to the aim of the study. Based on the review five measures are suggested: frequency, length, incidence rate, cumulative incidence and duration. The definition of incidence rate is new and is a measure useful in studies of recurrent events within epidemiology. CONCLUSIONS: We have reviewed sick-leave measures previously used in the literature and suggested five basic measures for assessing sick-leave.

Absenteeism↗

Comparison of methodologies for calculating quality measures based on administrative data versus clinical data from an electronic health record system: implications for performance measures.

New reimbursement policies and pay-for-performance programs to reward providers for producing better outcomes are proliferating. Although electronic health record (EHR) systems could provide essential clinical data upon which to base quality measures, most metrics in use were derived from administrative claims data. We compared commonly used quality measures calculated from administrative data to those derived from clinical data in an EHR based on a random sample of 125 charts of Medicare patients with diabetes. Using standard definitions based on administrative data (which require two visits with an encounter diagnosis of diabetes during the measurement period), only 75% of diabetics determined by manually reviewing the EHR (the gold standard) were identified. In contrast, 97% of diabetics were identified using coded information in the EHR. The discrepancies in identified patients resulted in statistically significant differences in the quality measures for frequency of HbA1c testing, control of blood pressure, frequency of testing for urine protein, and frequency of eye exams for diabetic patients. New development of standardized quality measures should shift from claims-based measures to clinically based measures that can be derived from coded information in an EHR. Using data from EHRs will also leverage their clinical content without adding burden to the care process.

Blood Pressure↗

Body composition in neonates: relationship between measured and derived anthropometry with dual-energy X-ray absorptiometry measurements.

This study examined the relationship between measured and derived anthropometric measurements with dual-energy X-ray absorptiometry measured lean and fat mass at 3.0 +/- 2.8 (SD) days in 120 neonates with birth weights appropriate (AGA; n=74), large (LGA; n=30); or small (SGA, n=16) for gestational age. Anthropometric measurements, including total body weight and length, and regional measurements, including circumferences of head, chest, abdomen, midarm, and midthigh and dynamic skinfold thickness (15 and 60 s) at tricep, subscapular, suprailiac, and midthigh, were performed. Derived anthropometry included muscle and fat areas, and ratios were calculated from direct measurements. The skinfold thickness measurements between 15 and 60 s were highly correlated (r=0.973-0.996, p <0.001 for all comparisons). Strong correlations existed within the four circumferences of trunk and extremities, the four skinfolds, and the ratios of weight to length and its higher powers. Weight and length accounted for >97% of the variance of lean mass in AGA and SGA infants and 46% of the variance in LGA infants and for 80, 82, and 84% of the variance of fat mass in SGA, AGA, and LGA infants, respectively, whereas midarm:head circumference ratio and arm muscle and fat areas are the most important derived anthropometry in the prediction for body composition. They independently accounted for up to 16.5 and 10.2%, respectively, of the variance in body composition depending on the state of in utero growth. Thus, total body weight and length and some selected regional and derived anthropometry accounted for the vast majority of the variance of body composition.

Absorptiometry, Photon↗

Correlation of environmental carbaryl measurements with serum and urinary 1-naphthol measurements in a farmer applicator and his family.

In exposure or risk assessments, both environmental and biological measurements are often used. Environmental measurements are an excellent means for evaluating regulatory compliance, but the models used to estimate body burden from these measurements are complex. Unless all possible routes of exposure (i.e., inhalation, dermal absorption, ingestion) are evaluated, exposure to a toxicant can be underestimated. To circumvent this problem, measurements of the internal dose of a toxicant in blood, serum, urine, or tissues can be used singularly or in combination with environmental data for exposure assessment. In three separate laboratories, carbaryl or its primary metabolite, 1-naphthol, was measured in personal air, dermal samples, blood serum, and urine from farmer applicators and their families. The usefulness of both environmental and biological data has been demonstrated. For the farmer applicator, the environmental levels of carbaryl would have been sufficient to determine that an exposure had occurred. However, biological measurements were necessary to determine the absorbed dose of each member of the applicator's family. In addition, a correlation between serum and urinary 1-naphthol measurements has been shown; therefore, either matrix can be used to accurately evaluate occupational carbaryl exposure.

Agriculture↗

Holographic common-path interferometer for angular displacement measurements with spatial phase stepping and extended measurement range.

A novel technique for extending the unambiguous measurement range for differential measurements of angular deflections is presented. The technique utilizes a common-path interferometer that simultaneously probes the out-of-plane displacement of three points on the object surface. The system is based on a single laser diode, and all the optical functions of the system are implemented in a dedicated holographic optical element (HOE). The HOE automatically provides spatially phase-stepped interference signals for real-time phase measurement. It is therefore not necessary to employ any polarizing optics or active elements to introduce the phase stepping. The common-path scheme combined with the HOE provides a system that is inherently stable, since the HOE operates as both transmitter and receiver in the system. The system is compact, is robust, and has the potential for being mass-produced at a low cost and is thus well suited for industrial use, such as in commercial vibrometers. The technique is demonstrated in a system for measuring angular deflections of a plane mirror. The technique, however, is not restricted to this use alone and can easily be configured to probe other types of surface displacements, e.g., the deflection of a diaphragm. In the present configuration, the system can measure angular deflections with a sensitivity of 2.5 x 10(-7) rad over a measurement range that is approximately 3.5 x 10(-3) rad, i.e., a dynamic range of approximately 1:14,000. Furthermore, the system can easily be reconfigured for a desired angular sensitivity and measurement range.

Journal Article↗

Inherent variability of CT lung nodule measurements in vivo using semiautomated volumetric measurements.

OBJECTIVE: The objective of our study was to evaluate repeatability and reproducibility of lung nodule volume measurements using volumetric nodule-sizing software. MATERIALS AND METHODS: Fifty nodules, less than 20 mm in diameter, in 29 patients were scanned with 1.25-mm collimation using MDCT (time 1 = T1). During the same session, two additional scans, using identical technique, were obtained through each nodule (T2, T3). Three observers working independently then obtained volumetric measurements using a semiautomated volumetric nodule-sizing software package. Qualitative nodule characterization was also performed. The Bland-Altman method for assessing measurement agreement was used to calculate the 95% limits for agreement for nodule volumes at T1, T2, and T3. RESULTS: Automated nodule segmentation was successful in 438 (97%) of 450 measurements. Forty-three nodules were available for final evaluation. Twenty-six nodules had well-defined edges, and 17 had irregular or spiculated margins. Seventeen were freestanding, 16 were juxtapleural, and 10 were juxtavascular in location. Average nodule volume was 345.5 mm(3) (range, 49.3-1,434 mm(3)). The mean interobserver variability (repeatability) was 0.018% (SD = 0.73%), and the SD of the mean for the three contemporaneous scans (reproducibility) was 13.1% (confidence limits, +/- 25.6%). SD and confidence limits narrowed as volumes increased. CONCLUSION: Volumetric measurements show minimal interobserver variability (0.018%) but an interscan SEM of 13.1% (confidence limits, +/- 25.6%). Repeatability and reproducibility of volumetric measurements are better than those of linear measurements reported in the literature.

Adult↗

Do measures of body fat distribution provide information on the risk of type 2 diabetes in addition to measures of general obesity? Comparison of anthropometric predictors of type 2 diabetes in Pima Indians.

OBJECTIVE: To investigate which anthropometric measurements of obesity best predict type 2 diabetes in a population of Pima Indians and whether additional information on diabetes risk could be obtained by combining measures of general obesity with measures of body fat distribution. RESEARCH DESIGN AND METHODS: We conducted a prospective study of 624 men and 990 nonpregnant women >18 years of age without diabetes. Subjects were followed a mean of 5.25 years for the development of type 2 diabetes (using 1997 American Diabetes Association criteria). RESULTS: A total of 322 new cases of type 2 diabetes (107 men and 215 women) were diagnosed during follow-up. Baseline obesity measurements were highly correlated and predicted diabetes in proportional hazards models adjusted for age. BMI had the highest hazard ratio in men and women, with age-adjusted hazard ratios per SD of 1.73 (95% CI 1.44-2.07) and 1.67 (1.45-1.91), respectively. According to receiver-operating characteristic analysis, BMI and waist-to-height ratio were the best predictors of diabetes in men, while in women BMI, waist-to-height ratio, waist circumference, and waist-to-thigh ratio were the best predictors. The predictive abilities of models containing BMI were not significantly improved by including other measures of general obesity or measures of the body fat distribution. CONCLUSIONS: Throughout its range, BMI was an excellent predictor of type 2 diabetes risk in Pima Indians and was not significantly improved by combining it with other measures of general adiposity or body fat distribution.

Adipose Tissue↗

Developing a tool to measure holistic practice: a missing dimension in outcomes measurement within complementary therapies.

Despite the wide and continuing debate over the relevance of particular research methods to evaluate complementary therapies, less attention has been given to what outcome criteria and measures to use and/or whether these have a sufficient breadth in perspective. While complementary and alternative medicine researchers have paid heed to the importance of measuring the subjective experience of therapy users, they have left unmeasured the notion of holism, in particular, the measurement of the effect of the interaction between therapist and therapy user, and its underlying philosophy of health and healing. This paper reports on an exploratory, qualitative study aimed at developing a measure of holism and holistic practice. It draws out some key features requiring measurement and provides insight into the emerging measure. Further development work is needed before the measure can be used within research or routine practice.

Complementary Therapies↗

Development of diagnostic thresholds for automated self-measurement of blood pressure in adults. First International Consensus Conference on Blood Pressure Self-Measurement.

Blood pressure is usually measured by conventional sphygmomanometry, a procedure fraught with many potential sources of error. Automated techniques of measurement, such as ambulatory monitoring and self-measurement, reduce the limitations of conventional sphygmomanometry. However, the diagnostic thresholds applicable for conventional sphygmomanometry cannot be extrapolated to automated measurements. During the past 10 years criteria for normality have gradually been developed for ambulatory blood pressure monitoring. First, the distributions of the ambulatory blood pressure in normotensive subjects and in untreated hypertensive patients who had initially been classified on the basis of their conventional blood pressure were studied. Second, epidemiological studies were performed to investigate the distribution of the conventional and ambulatory blood pressures in the population at large. Third, authors of several studies have now validated the preliminary thresholds for ambulatory monitoring against left ventricular hypertrophy, other signs of target-organ damage and the incidence of cardiovascular complications. Finally, authors of clinical trials investigated whether it is beneficial to patients and cost-effective to diagnose and treat hypertension on the basis of ambulatory monitoring rather than under the sole guidance of conventional sphygmomanometry. For systolic/diastolic measurements, the upper limits of normotension include 130/80, 135/85 and 120/70 mmHg for the 24 h, daytime and night-time blood pressures, respectively. Whereas for ambulatory monitoring a large body of evidence currently supports the proposed diagnostic thresholds, for the self-recorded blood pressure, to a large extent, this evidence must still be collected. In pursuing this goal, the methods applied for ambulatory monitoring may serve as a template. On the basis of a meta-analysis of summary statistics of published articles and a meta-analysis of data from individual subjects, 135/85 mmHg is likely to be the upper limit of normality for the self-measured blood pressure. Obviously, this threshold is preliminary and must be further validated in prognostic studies. However, the present proposal could guide clinicians who wish to use self-measurement to refine the diagnosis and the management of hypertension based on conventional sphygmomanometry.

Adult↗

The Rasch model, additive conjoint measurement, and new models of probabilistic measurement theory.

This research describes some of the similarities and differences between additive conjoint measurement (a type of fundamental measurement) and the Rasch model. It seems that there are many similarities between the two frameworks, however, their differences are nontrivial. For instance, while conjoint measurement specifies measurement scales using a data-free, non-numerical axiomatic frame of reference, the Rasch model specifies measurement scales using a numerical frame of reference that is, by definition, data dependent. In order to circumvent difficulties that can be realistically imposed by this data dependence, this research formalizes new non-parametric item response models. These models are probabilistic measurement theory models in the sense that they explicitly integrate the axiomatic ideas of measurement theory with the statistical ideas of order-restricted inference and Markov Chain Monte Carlo. The specifications of these models are rather flexible, as they can represent any one of several models used in psychometrics, such as Mokken's (1971) monotone homogeneity model, Scheiblechner's (1995) isotonic ordinal probabilistic model, or the Rasch (1960) model. The proposed non-parametric item response models are applied to analyze both real and simulated data sets.

Humans↗

Urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine values measured by an ELISA correlated well with measurements by high-performance liquid chromatography with electrochemical detection.

Measurement of urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) has recently become more popular as a means of assessing oxidative stress in the human body. Although using high-performance liquid chromatography with electrochemical detection (HPLC-ECD) is a reliable method of measuring 8-oxo-dG, easier and simpler alternative methods may be preferred, if they are quantitatively accurate. The ELISA method is the likeliest candidate for a useful alternative. Anti-8-oxo-dG monoclonal antibody N45.1 has been shown to have better specificity for 8-oxo-dG than other anti-8-oxo-dG antibodies, but the urinary 8-oxo-dG values measured by ELISA using N45.1 have been claimed to only weakly correlate with the values obtained by HPLC-ECD. Because the commercial ELISA kit has been improved, we compared the urinary 8-oxo-dG values measured by the ELISA with the values obtained by HPLC-ECD. We sampled the urine of 72 healthy Japanese individuals and measured their urinary 8-oxo-dG levels by the ELISA with appropriate controls and by HPLC-ECD. When X was defined as the values of 8-oxo-dG measured by HPLC-ECD, and Y was defined as the values of 8-oxo-dG measured by the ELISA, simple regression analysis showed the most likely relationship to be Y = 1.83X + 0.8. The correlation coefficient was 0.88, which indicated a good correlation between X and Y. These results show that the ELISA can be applied to studies comparing relative urinary 8-oxo-dG values among several groups, if the studies do not require determination of the exact concentration of 8-oxo-dG in urine.

8-Hydroxy-2'-Deoxyguanosine↗

Comparison of the accuracy of Canon KU-1 IOL measurer and VPLUS A/B scanner in axial length measurement.

PURPOSE: To evaluate the accuracy of Canon KU-1 IOL measurer (Japanese Canon Company) and VPLUS A/B scanner (French Quantel Company) in axial length (AL) measurement. METHODS: Canon KU-1 IOL measurer and VPLUS A/B scanner were used to measure axial length of human cataractous eyes before cataract surgery. Two hundred and twenty-two cases (433 eyes) were involved. The results were compared and the postoperative visual acuity, refractive results were recorded during the follow-ups to evaluate the accuracy of the two instruments. RESULTS: In the 222 cases (433 eyes), the absolute value of the measurement differences was 0.4 mm or above in 35 eyes, 0.8 mm or above in 17 eyes, 1.2 mm or above in 12 eyes, 2.0 mm or above in 5 eyes. The refractive error was less than 2.0 D in all patients. The mean values of ocular axial length by the two methods were 23.82 mm and 23.83 mm respectively and the difference had no statistic significance with compared t test (P = 0.902, two tail, alpha = 0.01). CONCLUSION: The accurate AL measurements can be obtained with the two instruments and the measurement results should be analyzed comprehensively to obtain accurate values in the complicated cases.

Adolescent↗

Partial control of Core Data Set measures and Disease Activity Score (DAS) measures of inflammation does not prevent long-term joint damage: evidence from longitudinal observations over 5-20 years.

Several reports concerning outcomes of rheumatoid arthritis (RA) document that measures of inflammatory activity [such as swollen joint count, tender joint count, and acute phase reactant, which are included in the Core Data Set or Disease Activity Score (DAS)] may be stable or improved over 5-10 years, while measures of damage (such as radiographic progression and joint deformity) may show contemporaneous progression. Therefore, studies which include only improvement in measures of disease activity cannot document overall improvement in patient status over 5-10 years. Studies designed to document favorable long-term effects of therapy in RA must include, at baseline and later follow-up evaluation, measures of damage, such as a radiograph, joint deformity, comorbidities, and extra-articular disease, in addition to measures of disease activity. The one prognostic measure which appears to detect both activity and damage in RA over short, intermediate, and long periods is a disability score on a patient questionnaire, which might be used by all rheumatologists at all patient encounters. The need for inclusion of accurate and relevant measures of damage appears of particular importance in the current era of biological drugs, in which the slowing or prevention of damage now appears a realistic goal in most patients with RA.

Antirheumatic Agents↗

Outcome measurement in HEDIS: can risk adjustment save the low birth weight measure?

OBJECTIVE: To evaluate whether adjusting the Health Plan Employer Data and Information Set (HEDIS) low birth weight (LBW) measure for maternal risk factors is feasible and improves its validity as a quality indicator. DATA SOURCE: The Washington State Birth Event Record Data for calendar years 1989 and 1990, including birth certificate data matched with mothers' and infants' hospital discharge records, with 5,837 records of singlet on infants identified as LBW (< 2,500 g) and a 25 percent sample ( n = 31,570) of the normal-weight births ( </= 2,500 g). STUDY DESIGN: We reviewed literature on factors associated with birth weight and identified factors for risk adjustment that are associated with LBW and th at are not modifiable by the health plan . We used vit al records Data to develop and test possible risk adjustment strategies. Finally, because feasibility is important for a HEDIS measure, we assessed health plan readiness to produce a risk-adjusted measure. PRINCIPAL FINDINGS: An LBW indicator that is adjusted for maternal risks represents health plan performance better than the unadjusted rate. In the most parsimonious risk adjustment model LBW risk was higher for mothers with a history of prior preterm birth , LBW, or fet al death . Risk was also high er for primiparas or mothers with high parity, mothers less than 19 years of age, and primiparas over age 35. In a model adding race to these obstetric factors, black, Asian/Pacific Islander, or other non-white, non-Hispanic race were also significantly associated with higher LBW risk. While adjusting for maternal risk improved the LBW measure's validity, the rate adjustment magnitude was small (0.17 percentage points) for the most plausible model. Th is may not be mean in gf ul clinically or for measuring differences in quality. The costs and data collection requirements of risk adjustment could be substantial for health plans lacking access to State birth records data. CONCLUSIONS Selection of risk adjusters for quality measures depends on judgments of their effect, legitimacy, and feasibility. A comprehensive examination of validity and feasibility is needed to understand to what extent outcome measures represent quality and how their value compares to their cost of collection .

Adult↗

[Measurement of cholesterol in capillary blood using the Reflotron system. Results from approximately 1,000 comparisons with reference measurements of cholesterol in venous serum].

The results of 969 measurements of total cholesterol in capillary blood from fingerstick, performed with the Reflotron-system in the field, were compared with measurements of total cholesterol in venous serum. The comparison allows an evaluation of the combined effect of differences in sample material, working place, stability of methods and staff training. The mean values for all measurement were nearly identical with the two methods, and approximately 95% of the Reflotron-measurements were within an interval of +/- 0.7 mmol/l around the estimated true value. However, values below approximately 6 mmol/l were systematically underestimated, and values above approximately 7 mmol/l were overestimated with the Reflotron-system. The coefficient of variation of the system is below 5%, but both this precision and the accuracy appear to be unstable. Evaluated as a tool in screening for hypercholesterolemia, measurements with the system resulted in a modest extent of erroneous classification of subjects, but the positive diagnostic predictive value of the statement "cholesterol above 7 mmol/l" is only approximately 76%. Simulations of likely variations in the accuracy and precision of the method show a significant influence on the extent of errors. It is recommended that measurements with the system are routinely controlled by measuring an appropriate control material, at the start of each run and after every 30 samples.

Adult↗

[Measurement of arterial pressure using 3 measurement methods in medial arterial calcification].

Medial calcification of the arteries, because of non-distensibility of the blood vessel walls, may overestimate the real intra-arterial pressure when blood pressure (BP) is measured by indirect sphygmomanometry cuff. In order to assess the best method for measuring BP, we compared direct intra-arterial measurements with indirect cuff sphygmomanometry as well as automatic oscillometric measurements in 15 hypertensive patients. Mean age +/- standard deviation (SD) was 62 +/- 9 years; all patients had medial calcifications of forearm and/or brachial arteries, and Osler's maneuver was negative in all. Ten sets of direct and indirect BP measurements were obtained for each patient. Results are expressed as mean +/- SD: (table; see text) There was no significant difference between cuff pressure and systolic intra-arterial pressure. The automatic oscillometric method underestimated systolic intra-arterial BP. Great individual variability was observed and could not be predicted clinically. Indirect diastolic BP values were greater than intra-arterial BP in all patients with the sphygmomanometer cuff and in 10 patients with the oscillometric recorder. There existed a direct relation between intra-arterial BP and differences between indirect BP measurements and intra-arterial BP as follows: intra-arterial BP was overestimated by indirect methods for values under 150 mmHg, and underestimated above 150 mmHg. In conclusion, invasive intra-arterial BP measurement seem to be necessary to distinguish between hypertensive and pseudo-hypertensive patients, in case of radiologic evidence of arterial calcification.

Aged↗