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Aneurysm is a major contributing factor to death and disability worldwide. This research explores the concept of using computational fluid dynamics (CFD) as a cost effective and non-invasive method to detect the location and condition of diseased segments of blood vessels. In this study, 12 different abdominal aortic aneurysms cases and a controlled case of 3D coupled fluid–structure interaction scheme (FSI) are modeled. Pulse waves travelling through these segments are analyzed with a focus on the reflected waves at diseased region and the brachial artery. A commercial software ANSYS 12.1® is used to solve FSI models. An invasive catheter pulsatile pressure waveforms data is imposed at the inlet and the four outlets of the aorta and also used to validate the presented models. The results show that an increase in the diameter of aneurysmal artery will have an effect on the systolic and diastolic pressure at the brachial artery. The systolic pressure increases due to the forward pulse wave resulting from aneurysm. However, diastolic pressure decreases due to the delay of the backward waves which reach at the brachial artery. These models show that the forward and backward waves, which can be attributed to changes in the diameter of the abdominal aorta, may be useful in diagnosing cardiovascular diseases non-invasively.

s 171 knowing whether reactivity of microvessels is different in young healthy adults with family history of hypertension and those without. Experiments were performed on 38 healthy adults 19-24 years old. We measured ECG, arterial blood pressure and laser-Doppler (LD) flux in the skin of the fingertips first at rest in the supine position, then 3 minutes while having legs passively raised and finally 3 minutes with having them put down to supine position again. Subjects were divided in two groups: those that had hypertension in family history (NZ17) and those that had not (NZ21). There were no differences in systolic and diastolic blood pressure or in RR interval between the two groups. The study has ethical approval and the consent has been obtained from each subject. The two groups of subjects showed significant difference in the LD flux while having legs lowered down again. Those without hypertension in family history exhibited greater LD flux than at rest (112.5 10%), while those with hypertension in family history exhibited smaller LD flux than at rest (83.6 8%) (t-test, p

The ATLAS Tile hadronic calorimeter (TileCal) provides highly-segmented energy measurements of incoming particles. The information from TileCal's last segmentation layer can assist in muon tagging and it is being considered for a future upgrade of the level-one trigger to reject triggers due to radiation background effects in the barrel region. A muon receiver for the TileCal muon signals is being designed in order to interface with the ATLAS level-one trigger. This paper addresses the preliminary studies concerning the muon discrimination capability for the muon receiver. Monte Carlo simulations for single muons from the interaction point were used to study the effectiveness of hadronic calorimeter information for muon detection.

This paper presents a 3D finite element upper arm model, validated by experiments as well as clinical data, used to study the error introduced in blood pressure measurements due to variability of arm tissue mechanical properties. The model consists of three separate cylindrical parts: soft tissue, bone and brachial artery. The artery volume changes under the cuff are used to represent the cuff pressure oscillations for analyzing blood pressure measurements. These oscillation trends are identical to observed clinical data. Also an upper arm simulator is designed and built for model validation. The model shows that the variation of soft tissue compressibility introduces an error up to 5% in blood pressure measurements. It is also revealed that the variation of the brachial artery and arm tissue stiffness has an insignificant effect on oscillometric blood pressure measurement method.

This study investigates whether individualized transfer functions for estimating central pressures can be derived based on statistical information on the physical properties of the forearm vasculature. Physical parameters of the uniform thin walled artery model are assigned based on clinical measurements and invasive pressure measurements (n = 20) are used to calculate the effective peripheral load. The calculated load is parameterized by a Windkessel model and the variation of the Windkessel parameters is analyzed with gender, age and height. Whilst there is high spread and poor correlation of the data with age and height, there is clear clustering of data with gender. This suggests that model parameters are significantly different in either gender, and gender-specific transfer functions might be more appropriate for accurate reconstruction of central pressure.Copyright © 2010 by ASME

In recent cardiovascular studies, the stress phase angle (SPA) has been used as a parameter to identify location for various diseases such as atherosclerosis and aneurysm. This angle represents the phase interaction between the wall shear stress (WSS) and the elastic strain intensity (ESI). It reflects the seriousness of WSS which is a direct measure of these diseases. In this work, a 3D model pulsatile flow in an artery is developed and used to calculate the SPA. Three different models are simulated and the changes in the SPA are observed.

In this paper we describe a proposed UK national approach to modelling decommissioning. For the first time, we shall have an insight into optimizing the safety and efficiency of a national decommissioning strategy. To do this we use the General Case Integrated Waste Algorithm (GIA), a universal model of decommissioning nuclear plant, power plant, waste arisings and the associated knowledge capture. The model scales from individual items of plant through cells, groups of cells, buildings, whole sites and then on up to a national scale. We describe the national vision for GIA which can be broken down into three levels: 1) the capture of the chronological order of activities that an experienced decommissioner would use to decommission any nuclear facility anywhere in the world — this is Level 1 of GIA; 2) the construction of an Operational Research (OR) model based on Level 1 to allow rapid what if scenarios to be tested quickly (Level 2); 3) the construction of a state of the art knowledge capture capability that allows future generations to learn from our current decommissioning experience (Level 3). We show the progress to date in developing GIA in levels 1 & 2. As part of level 1, GIA has assisted in the development of an IMechE professional decommissioning qualification. Furthermore, we describe GIA as the basis of a UK-Owned database of decommissioning norms for such things as costs, productivity, durations etc. From level 2, we report on a pilot study that has successfully tested the basic principles for the OR numerical simulation of the algorithm. We then highlight the advantages of applying the OR modelling approach nationally. In essence, a series of “what if[[ellipsis]]” scenarios can be tested that will improve the safety and efficiency of decommissioning.Copyright © 2009 by ASME

A model-based investigation is carried out with the aim of developing an ab-initio methodology for the patient-specific estimation of central pressures from brachial blood pressure readings. The subclavian root-brachial artery segment is modeled as a 1-D tube with all model parameters linked to patient characteristics. A simulation is also run with typical physiological parameters, which gives a “first estimate” of the transfer function (TF). The TF derived using the patient characteristics is studied in detail to investigate the change in the arterial TF occurring with changes in patient characteristics. This TF is compared with the “first estimate” to evaluate the feasibility of using standard arterial properties.Copyright © 2009 by ASME

A computer simulation technique based on individualised patient information is proposed for simulating pressure propagation characteristics of the systemic arterial tree. The technique relates physical properties of the systemic arterial tree to the gender, age and height of individual patients and uses a mathematical model of pressure propagation in elastic arteries to relate pressure and flow waveforms at different locations along the arterial tree. To verify that the technique is able to successfully model blood flow in the system, the model predictions are compared to invasive measurements of aortic blood pressure made during aortograms. Results suggest that the technique is able to simulate pressure propagation in a highly successful manner with a correlation coefficient >0.95 and a total cumulative errors less than 2% when compared with invasive measurements. Application of this technique in the diagnosis of different cardiovascular conditions is currently underway.

Non-invasive blood pressure (BP) measurement has been used clinically for over a century to diagnose hypertension. Compared with the auscultatory technique, the oscillometric technique requires less professional training and is widely used in automatic BP measurement devices. Currently, most of these devices measure and record amplitude of cuff pressure oscillation, and then calculate diastolic and systolic pressure using characteristic ratios and designed algorithms. A finite element (FE) model is developed to study the biomechanical basis of this technique. The model identifies that errors were caused by mechanical factors of the soft tissue and the shape of the arm. By personalizing the parameters for each patient, the accuracy of the measurement will be improved for all age groups.Copyright © 2009 by ASME

Elevated central arterial (aortic) blood pressure is related to increased risk of cardiovascular disease. Methods of non-invasively estimating this pressure would therefore be helpful in clinical practice. To achieve this goal, a physics-based model is derived to correlate the arterial pressure under a suprasystolic upper-arm cuff to the aortic pressure. The model assumptions are particularly applicable to the measurement method and result in a time-domain relation with two parameters, namely, the wave propagation transit time and the reflection coefficient at the cuff. Central pressures estimated by the model were derived from completely automatic, non-invasive measurement of brachial blood pressure and suprasystolic waveform and were compared to simultaneous invasive catheter measurements in 16 subjects. Systolic blood pressure agreement, mean (standard deviation) of difference was -1 (7)mmHg. Diastolic blood pressure agreement was 4 (4)mmHg. Correlation between estimated and actual central waveforms was greater than 90%. Individualization of model parameters did not significantly improve systolic and diastolic pressure agreement, but increased waveform correlation. Further research is necessary to confirm that more accurate brachial pressure measurement improves central pressure estimation.

In hypertension and aging, central elastic arteries become stiffer and hence the central pulse pressure is augmented due to the increase in the pulse wave velocity and the early return of reflected waves to the heart from the periphery. Valuable information on arterial properties, such as stiffness, can be obtained from both central (aortic) and peripheral (radial) pressure wave forms. A feasibility study for the noninvasive estimation of arterial stiffness using pressure waves detected by a pneumatic cuff wrapped around the upper arm is presented. The propagation and reflection of arterial pressure waves (generated by the heart) in the central elastic arteries are simulated using a simplified water hammer acoustic model. Furthermore, a lumped parameter model is used to describe the transmission of the pressure waves from the brachial artery to the cuff external wall. By combining the two models, we were able to simulate the pressure contours in the brachial artery and illustrate how these pressures transmit to the cuff’s external wall. The effects of aortic stiffness are investigated by simulating the model at different values of aortic elastic moduli and observing the pressure augmentation and the timing of feature points. This work was done as part of the development of a noninvasive diagnostic device by Pulsecor Ltd. The model results obtained in this work are in agreement with published experimental results and the device output; hence, the model can be used to develop the device’s stiffness estimation algorithm.

The human upper arm is simulated using a nonlinear geometrical and physical model. To create a more realistic simulation, the geometry of the model is based on the visible human body dataset. The model consists of four parts, humerus, brachial artery, muscle, and other soft tissues. All the materials used in this model are assumed to be incompressible and hyperelastic. The unique properties of each material are specified and described. Incorporating all of these facts, a finite element model is developed using the commercial programme ABAQUS® . The upper arm tissues’ deformations and artery collapse process under compression are simulated in this model. The proposed model has the potential to simulate the tissue deformations under inflatable cuffs exposed to arm movements.Copyright © 2008 by ASME

The propagation of pressure pulses between the carotid and the femoral artery is studied by calculating a pressure ratio (PR) between these locations. This ratio is parameterized into different features to permit a quantitative comparison between the PRs. The results obtained from such comparison suggest that it would be possible to non-invasively identify the size and severity of atherosclerotic plaque deposits by studying the features of the carotid-femoral PR.Copyright © 2008 by ASME

A Monte-Carlo simulation is developed to study the pressure propagation characteristics in a representative healthy randomly selected human population. Normal distribution sets are defined for different anatomic and physiological parameters based on data available in literature. Random input parameter sets are then generated from these distributions. A mathematical model is then used to simulate the pressure propagation characteristics in large elastic arteries defined by these input parameters. The pressure wave characteristics are then analysed to estimate carotid-femoral pulse wave velocity. Predictions closely match clinically observed trends.Copyright © 2008 by ASME

Expert algorithms in the field of intelligent patient monitoring have rapidly revolutionized patient care thereby improving patient safety. Patient monitoring during anesthesia requires cautious attention by anesthetists who are monitoring many modalities, diagnosing clinically critical events and performing patient management tasks simultaneously. The mishaps that occur during day-to-day anesthesia causing disastrous errors in anesthesia administration were classified and studied by Reason [1]. Human errors in anesthesia account for 82% of the preventable mishaps [2]. The aim of this paper is to develop a clinically useful diagnostic alarm system for detecting critical events during anesthesia administration. The development of an expert diagnostic alarm system called ;RT-SAAM' for detecting critical pathological events in the operating theatre is presented. This system provides decision support to the anesthetist by presenting the diagnostic results on an integrative, ergonomic display and thus enhancing patient safety. The performance of the system was validated through a series of offline and real-time testing in the operation theatre. When detecting absolute hypovolaemia (AHV), moderate level of agreement was observed between RT-SAAM and the human expert (anesthetist) during surgical procedures. RT-SAAM is a clinically useful diagnostic tool which can be easily modified for diagnosing additional critical pathological events like relative hypovolaemia, fall in cardiac output, sympathetic response and malignant hyperpyrexia during surgical procedures. RT-SAAM is currently being tested at the Auckland City Hospital with ethical approval from the local ethics committees.

Atherosclerosis is a major contributing factor to death and disability worldwide. It is implicated in coronary heart disease, stroke, peripheral arterial disease and bowel infarction. Catheter angiography is widely used in patients who suffer from this disease. Apart from the various risk factors and side effects associated with such a technique are the obvious high costs involved. This paper explores the concept of using acoustic waves as a cost effective and accurate method to detect the location and condition of diseased segments of blood vessels. The propagation and reflections of arterial pulse waves (generated by the contraction of the left ventricle) in the systemic arteries are simulated using a linearised acoustic model. The original wave travel to the brachial artery, iliac bifurcation and aorta is traced. The reflected wave that travels back up the aorta and into the brachial artery through the subclavian artery is also determined. By observing the time lag between the original and the reflected waves, the effects of arterial stiffness, geometry are studied by simulating the model at various stiffness, geometries. An algorithm to non-invasively identify the arterial stiffness variation is described.

Pancreatic body carcinoma has a poor prognosis with advanced disease at presentation. Recent experience at multidisciplinary team (MDT) meetings suggests increasing prevalence.Our aim was to determine if introduction of MDT meetings has affected the natural history of this disease.Retrospective diagnostic and survival data were collected from 1995 to 2006 at two large teaching hospitals, and divided into pre- and post 2003 groups (based on MDT introduction).Thirty-one patients with pancreatic body carcinoma (median age at diagnosis 72 years; range 43-87 years).Commonest symptoms at presentation were abdominal pain and weight loss. Eight patients (25.8%) were diagnosed pre MDT (median age 71.5 years, range: 60-87 years) and 23 patients (74.2%) were diagnosed post MDT (median age 67 years, range: 43-85 years; P=0.299 vs. pre MDT). There was a significantly (P=0.024) greater prevalence of more advanced tumours post MDT (stage IV: 15/23, 65.2%) than pre MDT (stage IV: 2/8, 25.0%). Neither tumour markers nor liver biochemistry differentiated tumour stage. Best supportive care was offered to 16 patients (51.6%) while 12 patients (38.7%) were suitable for chemotherapy: 2 out of 8 pre MDT (25.0%) and 10 out of 23 (43.5%) post MDT (P=0.433). For stage III tumours, post MDT patients tended to be younger (median 59 years vs. 74.5 years, P=0.042). Survival was not significantly increased after MDT introduction but chemotherapy offered significant survival benefit on multivariate analysis (P=0.042; hazard ratio: 0.39, 95% CI: 0.16-0.97).The trend is towards increased prevalence of pancreatic body cancer and more advanced disease at presentation. Chemotherapy was associated with a survival benefit, although the introduction of the MDT has not significantly altered disease management.

A physiologically-correct mathematical model of blood flow in the human aorta is developed from previously reported experimental data. The blood is assumed as a viscous fluid flowing through a compliant tube. This phenomenon is modeled by combining the Navier-Stokes’ equations and Laplace Law. The model is validated using experimental data collected at a leading specialist catheterisation laboratory. The mathematical model is then manipulated to derive a pressure transfer function between the aortic pressure and the pressure at the iliac bifurcation. The results of a comprehensive senstivity analysis carried out on this transfer function are discussed in this article. This study indicates that Coriolis and viscous effects insignificantly affect the wave propagation characteristics. The effect of arterial tapering on the transfer function is also recorded as insignificant. Changing the stiffness of the tube causes the pressure wave to travel faster through the system. The system natural frequency also increases when the tube wall is stiffened.Copyright © 2007 by ASME

A 10-year-old, spayed female, obese golden retriever, presented for immune-mediated thrombocytopenia, was successfully managed with the administration of vincristine and prednisone. However, 6 mo after discontinuing corticosteroid therapy because of suspected iatrogenic hyperglucocorticoidism, the patient was presented with multiple, firm, bilaterally symmetric, dermal masses composed histologically of differentiated cortical bone.

The microscopy trade-off between high-resolution and large-area imaging is eliminated by the use of an array microscope. We describe a system with 80 microscope objectives developed for scanning 30 microscope slides/hour at 54,045 dpi.

Mechanical obstruction of the large bowel is four to five times less common than that of the small bowel, but whereas the majority of small bowel obstructions are due to adhesions, in over half the cases large bowel obstruction is the result of a carcinoma. Other causes include volvulus (11%), diverticulitis (9%) and extrinsic infiltration by malignant disease (8%). Adhesions, faecal impaction and hernias are rarer causes (Table 26.1).

This paper presents an investigation into the sources of instability in geodetic GPS time transfers at the National Physical Laboratory (NPL). This investigation shows that for averaging times up to six hours, the delay instabilities of the NPL geodetic GPS receivers give the largest contribution to the overall geodetic GPS time transfer instability for a baseline of 5 m. Also, they make a significant contribution over a longer baseline of 750 km.

Nuclear decommissioning design and operational knowledge may remain relevant over many decades. Designing sustainable operations today requires meaningful simulation of future events, which in turn relies on the accurate representation of all relevant current knowledge. In decommissioning, human agents may be as important for maintaining operational safety as technical systems, so simulations must represent not just technical but tacit knowledge (embedded in practice) and the contextual and perceptual aspects of knowledge – i.e. how the meaning of data changes with the circumstances and viewpoint of stakeholders. We propose that this detail may be captured by ontological knowledge systems, which are augmenting traditional archives, databases or operational flowcharts in other highly interlinked, multidisciplinary, dynamic and highly specialised fields. Using the example of waste transport modelling, this study discusses how a coherent ontology unifying knowledge, physics and simulations could facilitate the design, assessment and communication of sustainable decommissioning.

This contribution examines the graphical presentation of decision support information generated by an intelligent monitor, named Sentinel, developed for use during anaesthesia. Clinicians make diagnoses in real-time during operations by examining clinically significant trends in multiple signals. Sentinel attempts to mimic this decision process by using a system of fuzzy trend templates. Sentinel's implementation of fuzzy trend templates is capable of providing the dual fuzzy measures of belief and plausibility, which are derived from the theory of evidence. It is thus capable of generating fairly rich diagnostic decision support information. However, for Sentinel to be effective, the visual presentation of this information must be intuitive to the anaesthetist, who may not be familiar with the theory of evidence. This paper discusses techniques that are being evaluated to meet the requirements of the Sentinel anaesthesia monitor. Specifically, the paper presents methods for highlighting clinically significant trends in physiological (or derived) signals by superimposing a coloured band on the signal that reflects fuzzy output from the intelligent monitor. This paper also discusses the intuitive graphical presentation of binary diagnostic fuzzy measures, including their further interpretation and presentation as crisp ''alarm'' and ''warning'' conditions.

A technique based on the concept of a ‘fuzzy trend template’ has been developed to identify characteristic patterns in multiple time-series. The method has its foundation in fuzzy logic and allows for the intuitive and transparent description of ‘templates’, which preserve nuances of vagueness, temporal relationships and quantitative descriptors. Evaluation of fuzzy trend templates can provide both belief and plausibility information for use in diagnostic applications. The technique has been applied to the diagnosis of specific problems in anaesthesia and has demonstrated sensitivity and specificity of 95 and 65%, respectively. Evaluation of fuzzy trend templates is, computationally, relatively efficient and has allowed a real-time implementation. The technique has the potential to be useful in any domain that requires temporal pattern recognition based on linguistic rules.

A computer program using fuzzy logic templates has been developed to enhance the diagnosis of malignant hyperpyrexia. When tested, retrospectively, against the physiological changes that occurred during the onset of a bona fide malignant hyperpyrexia episode it made the diagnosis about 10 minutes before the anaesthetist. When tested against the changes associated with laparoscopic surgery, which has certain similarities, the diagnosis of malignant hyperpyrexia was very transient. The use of this program may assist the anaesthetist in the diagnosis of this rare event.

To the Editor .— In a recent commentary in Pediatrics , Yogev1 advocates moving forward with annual influenza immunizations for preschool- and school-aged children. He cites ample evidence, from the Japanese experience in the 1970s to more recent studies and statistical projections, for a significant benefit to such a program in the United States. The evidence cited strongly suggests that immunizing children, in addition to current priority recipients, will lead to a further reduction in morbidity, mortality, and economic loss each winter season. The evidence supports immunizing children for maximum benefit rather than infants and the elderly in years with a vaccine shortage. Yogev suggests using the live attenuated intranasal influenza vaccine (LAIV) for school-aged children and the inactivated vaccine for preschool-aged children. A more recent study that tracked the timing of positive influenza cultures according to age for 3 winter seasons at 6 Massachusetts health care settings identified preschool-aged children as the harbingers of influenza each season.2 Positive cultures from 3- to 4-year-old children preceded the peak of influenza …

Few studies have examined whether central arterial wavTable:eform measures vary with ethnicity. We aimed to provide a more comprehensive examination of ethnic differences in several cardiovascular risk factors, which may reveal new ethnic variations. A cross-sectional (baseline) analysis of 5110 adults (2971 M, 2139 F; age range, 50–84 years) from multiple ethnic groups (European/Other, Maori, Pacific, South Asian) participating in a New Zealand clinical trial of the effect of vitamin D supplementation (the ViDA study) on cardiovascular disease events was carried out. Peripheral blood pressure was measured with an Omron T9P oscillometric device. Arterial pressure waveforms were derived from suprasystolic brachial measurement using a Pulsecor R6.5 device, which previously has been shown to yield central pressure measurements highly correlated with those from aortic catheterisation. These were decomposed into forward- and backward-travelling waves and reservoir wave analysis was applied to derive reservoir and excess pressures. Compared to European/Other participants, those in the other three ethnic groups had significantly higher peripheral augmentation index after adjustment for age, sex and BMI (Table). Other ethnic differences in arterial waveform parameters and morphologies will be reported, including those derived from reservoir wave analysis. In conclusion, arterial function varies across ethnic groups. Longitudinal analyses will be carried out after 4 years follow-up to determine if arterial waveform measures predict cardiovascular disease incidence. Funding: Health Research Council of New Zealand Measure Mean (SE)* European/Other (n=2959) Mean difference (SE)* from European/Other P-value# Maori (n=194) Pacific (n=254) South Asian (n=139) Brachial BP (mmHg) Systolic 139.5 (0.4) 2.9 (1.4) 2.4 (1.2) −2.1 (1.6) 0.019 Diastolic 76.9 (0.2) 2.0 (0.7) 0.7 (0.7) −1.5 (0.9) 0.009 Peripheral augmentation Index % 100.6 (0.9) 8.8 (2.9) 3.2 (2.7) 5.8 (3.4) 0.009 *Adjusted for age, sex and BMI; #P-value for variation across all 4 ethnic groups. Table:Preliminary data from the ViDA study.

Background: An implantable cardioverter-defibrillator (ICD) is a treatment associated with significant cost and risk of morbidity. Elderly patients (arbitrarily defined as age≥ 75 years old) were under-represented in large clinical trials (e.g. MADIT-II and SCD-HeFT) which showed a mortality benefit with ICD implantation in patients with reduced left ventricular function. Thenetmortality benefit for this age group is unclear and there is no New Zealand data available. Aim: The aim of this study was to ascertain survival in elderly patients who have had ICDs implanted. The secondary objective was to document device related morbidity. Methods: This was a descriptive study with retrospective data collection on 41 patients age≥ 75 years old living in the Auckland region who received ICDs between 1st January 2000 to 31st December 2010. Demographic, clinical and survival data were collected retrospectively from Auckland District Health Board (DHB), Counties Manukau DHB, Waitamata DHB and regional ICD databases. Results: The total number of deaths was 15 (37%), eight cardiac and seven non cardiac. One and two year mortality rates were 2.4% (1/41) and 14.6% (6/41) respectively. Twenty patients (48.8%) received appropriate therapy while fivepatients (12.2%) received inappropriate therapy. Other device relatedmorbidity includes five implant complications (12.2%), five generator complications (12.2%) and one lead complication (2.4%) during follow up. Conclusions:While the total numberofpatients is small, our data support the value of ICD implantation in carefully selected elderly patients. Device related morbidity is acceptable.

Results: The distribution of AASI-values, obtained from 10000 ABPM simulations (each using 72 BP-values randomly selected among 3125) was normal (AASIZ0.43 0.04 (SD)). An increase in heart rate, distensibility or resistance from 80 to 120% of its default value caused the AASI to decrease by 37, 21 or 9%, respectively. Whereas there was no overlap in the distensibility ranges for the three theoretical subjects, the was considerable overlap between the AASI distributions. Conclusion: The confounding effects of resistance and heart rate limit the use of AASI as a marker of stiffness.

Objective:To assess the effect of age and gender on suprasystolic acquired indices of vascular stiffness using a novel device – Pulsecor® R6.5.Design:Suprasystolic blood pressure measurements were taken in 294 subjects from primary care facilities in Auckland, New Zealand. Three measurements were ta