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The Framingham risk equations are widely used to estimate risk of coronary heart disease (CHD). The purpose of this study was to evaluate the reliability of these equations in predicting CHD risk in people with diabetes and the reliability of using imputed mean HDL-cholesterol values. Data describing the baseline characteristics of recognized CHD risk factors for 938 people aged 30–74 years were extracted from the Cardiff Diabetes Database. Data describing CHD events were available for up to 4 years following the baseline year (1996). Several mathematical techniques were used to assess the reliability of predictions provided by the Framingham equations in this population. Thirty-four percent of males and 25% of females who experienced CHD events had a predicted 10-year CHD risk ≥ 30%. Seventy-five percent of males and 58% of females had a predicted 10-year CHD risk ≥ 20%. Using imputed HDL-cholesterol values, 26% of males and 6% of females who later developed CHD events had a 10-year CHD risk ≥ 30%. Using imputed HDL-cholesterol values, the CHD risk predicted by the Framingham equations consistently underestimated the actual risk of CHD events. However, refitting the Framingham risk equations to the Cardiff data resulted in only marginal improvements in discriminatory capabilities. The Framingham risk equations can be unreliable when applied to the diabetic population, tending to underestimate an individual's probability of progressing to CHD; the equations perform marginally better in women than in men. The use of imputed mean HDL-cholesterol values improved the reliability of the estimates of risk. Diabet. Med. (2004) [ABSTRACT FROM AUTHOR]

OBJECTIVE:: To determine and compare the extent of within- and between-laboratory precision in body volume (BV) measurements using air displacement plethysmography (ADP), the BOD POD body composition system, and to interpret any such variability in terms of body composition estimates. DESIGN:: Repeated test procedures of BV assessment using the BOD POD ADP were reproduced at two laboratories for the estimation of precision, both within and between laboratories. SUBJECTS:: In total, 30 healthy adult volunteers, 14 men (age, 19-48?y; body mass index (BMI), 19.7-30.3?kg/m2) and 16 women (age, 19-40?y; BMI, 16.3-35.7?kg/m2), were each subjected to two test procedures at both laboratories. Two additional volunteers were independently subjected to 10 repeated test procedures at both laboratories. MEASUREMENTS:: Repeated measurements of BV, uncorrected for the effects of isothermal air in the lungs and the surface area artifact, were obtained using the BOD POD ADP, with the identical protocol being faithfully applied at both laboratories. Uncorrected BV measurements were adjusted to give estimates of actual BV that were used to calculate body density (body weight (BWt)/actual BV) from which estimates of body composition were derived. The differences between repeated BV measurements or body composition estimates were used to assess within-laboratory precision (repeatability), as standard deviation (SD) and coefficient of variation; the differences between measurements reproduced at each laboratory were used to determine between-laboratory precision (reproducibility), as bias and 95% limits of agreement (from SD of the differences between laboratories). RESULTS:: The extent of within-laboratory methodological precision for BV (uncorrected and actual) was variable according to subject, sample group and laboratory conditions (range of SD, 0.04-0.13?l), and was mostly due to within-individual biological variability (typically 78-99%) rather than to technical imprecision. There was a significant (P<0.05) bias between laboratories for the 10 repeats on the two independent subjects (up to 0.29?l). Although no significant bias (P=0.077) was evident for the sample group of 30 volunteers (-0.05?l), the 95% limits of agreement were considerable (-0.68 to 0.58?l). The effects of this variability in BV on body composition were relatively greater: for example, within-laboratory precision (SD) for body fat as % BWt was between 0.56 and 1.34% depending on the subject and laboratory; the bias (-0.59%) was not significant between laboratories, but there were large 95% limits of agreement (-3.67 to 2.50%). CONCLUSION:: Within-laboratory precision for each BOD POD instrument was reasonably good, but was variable according to the prevailing conditions. Although the bias between the two instruments was not significant for the BV measurements, implying that they can be used interchangeably for groups of similar subjects, the relatively large 95% limits of agreement indicate that greater consideration may be needed for assessing individuals with different ADP instruments. Therefore, use of a single ADP instrument is apparently preferable when assessing individuals on a longitudinal basis.International Journal of Obesity (2004) 28, 80-90. doi:10.1038/sj.ijo.0802466 [ABSTRACT FROM AUTHOR]

Valid assessment of physical activity is important to researchers and practitioners interested in surveillance, screening, programme evaluation and intervention. The validity of an assessment instrument is commonly considered its most important attribute. Convergent validity is the extent to which an instrument's output is associated with that of other instruments intended to measure the same exposure of interest. A systematic review of the literature produced 25 articles directly relevant to the question of convergent validity of pedometers against accelerometers, observation, and self-reported measures of physical activity. Reported correlations were pooled and a median r-value was computed. Pedometers correlate strongly (median r = 0.86) with different accelerometers (specifically uniaxial accelerometers) depending on the specific instruments used, monitoring frame and conditions implemented, and the manner in which the outputs are expressed. Pedometers also correlate strongly (median r = 0.82) with time in observed activity. Time in observed inactivity correlated negatively with pedometer outputs (median r = -0.44). The relationship with observed steps taken depended upon monitoring conditions and speed of walking. The highest agreement was apparent during ambulatory activity (running, walking) or during sitting (when both observation and pedometers would register few steps taken). There was consistent evidence of reduced accuracy during slow walking. Pedometers correlate moderately with different measures of energy expenditure (median r = 0.68). The relationship between pedometer outputs and energy expenditure is complicated by the use of many different direct and indirect measures of energy expenditure and population samples. Concordance with self-reported physical activity (median r = 0.33) varied depending upon the self-report instrument used, individuals assessed, and how pedometer outputs are expressed (e.g. steps, distance travelled, energy expenditure). Pedometer output has an inverse relationship with reported time spent sitting (r = -0.38). The accumulated evidence herein provides ample support that the simple and inexpensive pedometer is a valid option for assessing physical activity in research and practice. [ABSTRACT FROM AUTHOR]

Examines the influence of a strategy for change involving guidelines of good practice, monitoring and peer review on hospital radiology referral practice in Great Britain. Perception of doctors on the standards of clinical practice set by peers; Significance of the study on the deficiencies in National Health Service (NHS) hospitals; Resolutions for agreed standards of practice.

Examines the use of radiography of injured arms and legs in Great Britain. Effectivity of extremity radiography; Differences between centers and actual yields of bony injury; Importance of guidelines for the selection of extremity radiography for the quality improvement of the practice.

Presents updates from the U.S. Centers of Disease Control and Prevention as of July 17, 2002. Trends in cigarette smoking among high school students between 1991 and 2001; State-specific mortality from stroke and distribution of place of death in the U.S. in 1999.

Focuses on a high-performance native-oxide coupled-stripe Al[sub y]Ga[sub 1-y]As-GaAs-In[sub x]Ga[sub 1-x]As quantum well heterostructure laser realized by the introduction of a simple process of wet oxidation. Fabrication of the coupled-stripe laser; Effects of oxide on the operation of the laser arrays.

Evaluates the diagnostic accuracy of clinical examination, xeromammography, and fine-needle aspiration cytology in the diagnosis of breast tumors in Great Britain. Comparison with definitive histological findings; Percentage of diagnostic accuracy; Effect of the availability of accurate cytology on patient management.