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The Southampton examination schedule for the diagnosis of musculoskeletal disorders of the upper limb.

OBJECTIVES: Following a consensus statement from a multidisciplinary UK workshop, a structured examination schedule was developed for the diagnosis and classification of musculoskeletal disorders of the upper limb. The aim of this study was to test the repeatability and the validity of the newly developed schedule in a hospital setting. METHOD: 43 consecutive referrals to a soft tissue rheumatism clinic (group 1) and 45 subjects with one of a list of specific upper limb disorders (including shoulder capsulitis, rotator cuff tendinitis, lateral epicondylitis and tenosynovitis) (group 2), were recruited from hospital rheumatology and orthopaedic outpatient clinics. All 88 subjects were examined by a research nurse (blinded to diagnosis), and everyone from group 1 was independently examined by a rheumatologist. Between observer agreement was assessed among subjects from group 1 by calculating Cohen's kappa for dichotomous physical signs, and mean differences with limits of agreement for measured ranges of joint movement. To assess the validity of the examination, a pre-defined algorithm was applied to the nurse's examination findings in patients from both groups, and the sensitivity and specificity of the derived diagnoses were determined in comparison with the clinic's independent diagnosis as the reference standard. RESULTS: The between observer repeatability of physical signs varied from good to excellent, with kappa coefficients of 0.66 to 1.00 for most categorical observations, and mean absolute differences of 1.4 degrees -11.9 degrees for measurements of shoulder movement. The sensitivity of the schedule in comparison with the reference standard varied between diagnoses from 58%-100%, while the specificities ranged from 84%-100%. The nurse and the clinic physician generally agreed in their diagnoses, but in the presence of shoulder capsulitis the nurse usually also diagnosed shoulder tendinitis, whereas the clinic physician did not. CONCLUSION: The new examination protocol is repeatable and gives acceptable diagnostic accuracy in a hospital setting. Examination can feasibly be delegated to a trained nurse, and the protocol has the benefit of face and construct validity as well as consensus backing. Its performance in the community, where disease is less clear cut, merits separate evaluation, and further refinement is needed to discriminate between discrete pathologies at the shoulder.

Adult↗

Changes in proportions of empty body depots and constituents for nine breeds of cattle under various feed availabilities.

Mature cows (146) representing Angus, Braunvieh, Charolais, Gelbvieh, Hereford, Limousin, Pinzgauer, Red Poll, and Simmental breeds were slaughtered to contribute to the investigation of the effect of various feed availabilities on body composition. Weights recorded when cows were placed on feed were used to set daily diets at four rates of intake within each breed (55, 76, 96, and 111 g DM/[kg wt.75.d]). Cows remained on their assigned daily feed allotment throughout the study (3 to 5 yr). On the day of slaughter, shrunk live weights were recorded. Chemical determinations of protein (nitrogen x 6.25), ether extractable lipid, ash of dry matter, and moisture for hide and offal were obtained for all cows. Chemical determinations of these same constituents were obtained for the carcass soft tissue of 98 cows. Relationships among estimator traits carcass ash, warm carcass weight, resistive impedance, and carcass water from the 97 carcasses were used to predict the carcass constituents for the remaining 49 cows. Within breed, relationships between proportions of fat and empty body (sum of fat, ash, water, and protein from the three body pools of hide, offal, and carcass) were used to estimate empty body weight at 251 g fat/kg (standard reference body weight) for each of the nine breeds. Proportions of offal, carcass, hide, chemical constituents, and selected abdominal and thoracic organs relative to empty body weight from cows that attained weight stasis were regressed on one minus the ratio of individual actual empty body weight to breed standard reference weight. Among mature cows attaining weight stasis at various feeding rates, the proportion of offal remained constant, proportions of fat in carcass, hide, and offal increased with increasing feed level, and proportions of water and protein decreased. Significant variation (P < .01) attributable to breed in proportions of carcass, offal, hide, chemical constituents of the hide and offal, water, and protein of the carcass and selected organs was observed.

Abdomen↗

Novel use of single X-ray absorptiometry for measuring breast density.

Breast density is one of the strongest known breast cancer risk factors. Breast density has primarily been measured by either categorical scores of the proportion of opacity on a screening mammogram or as a ratio of the delineated dense area to the total breast area on a mammogram. These methods are limited by their subjectivity, their lack of absolute reference standards, and lack of automation for clinical use. We present a novel automated method for measuring breast composition we call Breast Compositional Density measured using single X-ray absorptiometry techniques, or BD(SXA). BD(SXA) measures breast compositional density by comparing the opacity on the mammogram to two reference standards imaged with each breast. We present the mathematical derivation of BD(SXA), methods for correcting for radiographic nonuniformity in the mammogram, and in vitro measures of accuracy and repeatability. Using phantoms, BD(SXA) has been shown to have a long-term repeatability of better than 2% for a breast composition range of 0 to 100% fibroglandular density.

Absorptiometry, Photon↗

Methodological quality and outcomes of studies addressing manual cervical spine examinations: a review.

The aims of this review were, first to rate the methodological quality of studies which investigate the reliability of manual tests for cervical spine dysfunctions by applying a new quality assessment tool; secondly to compare the outcomes of these studies. The literature search included databases of CINAHL, MEDLINE, AMED, AMI, and SPORT DISCUS, the Cochrane Library, the Physiotherapy Evidence Database (PEDro), the National Library of Medicine (PubMed), Factiva, the EBSCOT HOST Research Database, online journal databases of ELSEVIER Science periodicals, LIPPINCOTT WILLIAMS & WILKINS, ELSEVIER Science @ Direct, THIEME ONLINE, and BLACKWELL SYNERGY. The application of the Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS) to the 15 studies which met the inclusion criteria showed methodological weaknesses such as not considering an independent reference standard, or a representative study population. The studies demonstrated methodological strength in describing selection criteria and in interpreting results. The studies' outcomes make the claim to be able to detect segmental cervical dysfunction based on a manual assessment only questionable. Further improvements in quality, uniform study designs, and a valid reference standard would be necessary in order to obtain more reliable data in the future.

Cervical Vertebrae↗

Development and validation of methods for assessing the quality of diagnostic accuracy studies.

OBJECTIVES: To develop a quality assessment tool which will be used in systematic reviews to assess the quality of primary studies of diagnostic accuracy. DATA SOURCES: Electronic databases including MEDLINE, EMBASE, BIOSIS and the methodological databases of both CRD and the Cochrane Collaboration. REVIEW METHODS: Three systematic reviews were conducted to provide an evidence base for the development of the quality assessment tool. A Delphi procedure was used to develop the quality assessment tool and the information provided by the reviews was incorporated into this. A panel of nine experts in the area of diagnostic accuracy studies took part in the Delphi procedure to agree on the items to be included in the tool. Panel members were also asked to provide feedback on various other items and whether they would like to see the development of additional topic and design specific items. The Delphi procedure produced the quality assessment tool, named the QUADAS tool, which consisted of 14 items. A background document was produced describing each item included in the tool and how each of the items should be scored. RESULTS: The reviews produced 28 possible items for inclusion in the quality assessment tool. It was found that the sources of bias supported by the most empirical evidence were variation by clinical and demographic subgroups, disease prevalence/severity, partial verification bias, clinical review bias and observer/instrument variation. There was also some evidence of bias for the effects of distorted selection of participants, absent or inappropriate reference standard, differential verification bias and review bias. The evidence for the effects of other sources of bias was insufficient to draw conclusions. The third review found that only one item, the avoidance of review bias, was included in more than 75% of tools. Spectrum composition, population recruitment, absent or inappropriate reference standard and verification bias were each included in 50-75% of tools. Other items were included in less than 50% of tools. The second review found that the quality assessment tool should have the potential to be discussed narratively, reported in a tabular summary, used as recommendations for future research, used to conduct sensitivity or regression analyses and used as criteria for inclusion in the review or a primary analysis. This suggested that some distinction is needed between high- and low-quality studies. Component analysis was considered the best approach to incorporate quality into systematic reviews of diagnostic studies and this was taken into consideration when developing the tool. CONCLUSIONS: This project produced an evidence-based quality assessment tool to be used in systematic reviews of diagnostic accuracy studies. Through the various stages of the project the current lack of such a tool and the need for a systematically developed validated tool were demonstrated. Further work to validate the tool continues beyond the scope of this project. The further development of the tool by the addition of design- and topic-specific criteria is proposed.

Delphi Technique↗

An amplified ELISA inhibition method for the measurement of airborne soybean allergens.

BACKGROUND: Measurement of the soybean aeroallergen in Barcelona and other cities where soybean is unloaded is of increasing importance in controlling population exposure and evaluating the influence of such exposure on the persistence of asthma symptoms. OBJECTIVE: The aims of the study were: (1) to standardize an amplified ELISA inhibition method for the quantification of soybean aeroallergen and (2) to compare this method to a previously described RAST inhibition method. METHODS AND RESULTS: An amplified competitive ELISA inhibition method with a biotin-streptavidin system was carried out using a pool of sera from soybean-sensitized patients. The results were expressed as U/ml using a low-molecular-mass soybean allergen as reference standard. Reproducibility was calculated by statistically comparing the slope of the regression lines of the standard curve of 4 consecutive assays and by determining the coefficient of variation (CV) of the percent inhibition data for each point of several independent standard curves, each from the same assay (intra-assay) and also from a separate assay (inter-assay). No significant differences in the slopes were obtained by analysis of covariance (ANCOVA) F = 1.04. The CV between assays varied between 4 and 22% (for the assay range used in the reference standard) and was greater than the CV within assays (5-10%). Only values with a CV(%) smaller than 20% were considered acceptable. 78.5% of the samples satisfied this criterion. The RAST inhibition and ELISA inhibition methods were compared by difference plots from the values of 338 air filter eluates. The intraclass correlation coefficient was 0.456 (p < 0.001). After the results of both methods were classified as lower and higher than 165 U/m(3), the kappa index was 0.46 (p < 0.001). CONCLUSIONS: The data obtained in the present study are comparable to those reported from other similar immunoassays. Moreover, despite the difficulty in comparing air-sampling values from different laboratories, the kappa index may be taken to represent fairly good agreement beyond chance between both methods. All these data demonstrate that the present immunoassay is useful for measuring airborne soybean aeroallergens and can also be applied to evaluate the relationship between exposure and the development of asthma symptoms.

Air Pollutants↗

Carotid artery: elliptic centric contrast-enhanced MR angiography compared with conventional angiography.

PURPOSE: To determine the accuracy of elliptic centric contrast material-enhanced magnetic resonance (MR) angiography by using conventional angiography as the reference standard. MATERIALS AND METHODS: Fifty patients were examined prospectively with contrast-enhanced MR angiography and conventional angiography. The two examinations were performed within 1 week of each other. Two patients underwent conventional angiography of only one carotid artery, which yielded 98 arteries for comparison. RESULTS: With conventional angiography as the reference standard and by using a 70% threshold for internal carotid arterial diameter stenosis, maximum intensity projection (MIP) images had a sensitivity of 93.3%, specificity of 85.1%, and accuracy of 87.6%, whereas reformatted transverse source images had a sensitivity of 83.3%, specificity of 97.0%, and accuracy of 92.8%. Interobserver variability for conventional angiograms was 0.97, for MIP images was 0.91, and for source images was 0.90. The contrast-enhanced MR angiographic technique had a sensitivity of 88.9% and specificity of 58.1% for the presence of irregularity and/or ulceration. All 50 examinations were triggered appropriately so that minimal or no venous signal intensity was depicted. CONCLUSION: Contrast-enhanced elliptic centric three-dimensional MR angiography offers high-spatial-resolution, venous-suppressed images of the carotid arteries that appear to be adequate to replace conventional angiography in most patients examined prior to carotid endarterectomy.

Aged↗

[Nutritional anthropometry and physical performance in urban adolescents of Madrid].

OBJECTIVE: This work has been carried out as a cooperation project between University and High School Departments. Its objective was to evaluate the nutritional and physical status and eating habits in an urban adolescent population of Madrid. The study presents data about anthropometrical analyses and physical performance. SAMPLE AND METHODS: The sample analyzed was composed of 183 males and 222 females between 14 and 18 years of age. The nutritional status was analyzed by means of stature, weight, skinfold thickness and arm circumference, body mass index (BMI), and lean, fat and total upper arm areas. For physical fitness analysis, the EUROFIT battery was used (plate tapping, trunk and arm flexion, 10 x 5 run, horizontal jump, abdominals in 30 seconds and manual dynamometry). RESULTS AND CONCLUSIONS: With regard to the anthropometric characteristics and physical fitness, the analyzed population is slightly above the reference standard, mainly in the youngest age studied. Percentage of obese subjects was 14.7% in males and 5.8% in females. In regard to physical fitness, the males surpassed the 50th percentile of the EUROFIT battery in almost all of the trials. The average in the female subjects was slightly inferior to the reference standards.

Adolescent↗

Comparison of electrocardiogram interpretations by family physicians, a computer, and a cardiology service.

BACKGROUND: Some family physicians may be under pressure to relinquish the interpretation of outpatient electrocardiograms to cardiologists. The purpose of this study was to determine whether the quality of electrocardiogram (ECG) interpretations by family physicians justifies this pressure, and whether an immediately available computerized ECG interpretation program could serve as an appropriate backup for the family physician. METHODS: Family practice faculty and residents at a university-based residency program provided written interpretations of 301 ECGs ordered over an 11-month period. Their ECG findings were compared with those from a computerized interpretation program and the readings of the cardiology service. All interpretations were then compared with those of a fellowship-trained electrocardiographer, whose readings served as the reference standard. RESULTS: Discrepancy was found between the family physician and the electrocardiographer on 33% of those items that had any potential clinical significance. The computer interpretation and the cardiologist's interpretation agreed with that of the electrocardiographer on 63% and 71% of these discrepancies, respectively (not statistically different). CONCLUSIONS: Family physicians reached a level of agreement with the reference standard in ECG interpretation that was comparable to previously published reports for expert interrater agreement. In this study, however, the quality of ECG readings by family physicians was further improved by expert review. The quality of computer-assisted ECG interpretation was comparable to that of review provided by a cardiology service. Furthermore, computerized interpretation may be clinically more useful because it is immediately available.

Aged↗

Diagnostic accuracy of nuclear STAT6 immunohistochemistry for solitary fibrous tumour: a systematic review and meta-analysis.

Nuclear STAT6 immunohistochemistry is the diagnostic surrogate for the NAB2::STAT6 fusion of solitary fibrous tumour (SFT); its sensitivity is established, but specificity varies for unexamined reasons. This review quantified pooled accuracy and tested whether antibody clone and nuclear threshold govern specificity. PubMed, Scopus and Web of Science were searched to 29 June 2026 for studies reporting nuclear STAT6 immunohistochemistry against a reference standard (NAB2::STAT6 confirmation and/or expert consensus) in SFT and comparators, with extractable two-by-two data. Two reviewers screened, extracted data and applied QUADAS-2. A bivariate generalised linear mixed model gave summary sensitivity and specificity, and exploratory subgroup analysis and meta-regression tested antibody clone, anatomical site and reference-standard type. Twenty-three studies (1216 SFT and 4715 comparators) were included. Summary sensitivity was 98.7% (95% confidence interval 96.7-99.5) and specificity 99.1% (97.8-99.6); the diagnostic odds ratio was approximately 8656. The monoclonal YE361 subgroup (8 studies) reached specificity 99.9% (99.3-100), with one false positive among 861 comparators, versus 98.1% (96.0-99.1) for polyclonal and other antibodies. False positives concentrated in dedifferentiated liposarcoma and prostatic stromal tumours. Estimates were stable after removing studies at higher risk of bias (98.9%/99.1%) and on leave-one-out analysis; the Deeks test was non-significant (p&#xa0;=&#xa0;0.08). Nuclear STAT6 immunohistochemistry is therefore highly sensitive and specific for SFT, and the residual specificity loss is structured and largely avoidable: the monoclonal YE361 read at a strict nuclear threshold is preferred, with MDM2 and CDK4 applied to exclude dedifferentiated liposarcoma when nuclear STAT6 is unexpectedly positive.

Humans↗

Using standards and controls in molecular assays for infectious diseases.

Ten years ago, laboratory directors introducing molecular infectious disease diagnostics in the routine clinical setting had few resources to assist in their implementation and quality assurance programs. In the past 10 years, several organizations have recognized this need and have established standard reference materials, controls, external quality assessment programs, and written guidelines. It is a challenge for the clinical laboratory scientist to evaluate and incorporate these new programs and services in the context of traditional good laboratory practice and current laboratory regulations. This article presents many of the options available for control materials, proficiency programs, standard reference materials, and written guidelines. It shows where harmonization of new practice with long-standing convention and regulation is progressing and where questions remain.

Communicable Disease Control↗

Accuracy of urinalysis dipstick techniques in predicting significant proteinuria in pregnancy.

OBJECTIVE: To estimate the accuracy of point-of-care dipstick urinalysis in predicting significant proteinuria in pregnancy. DATA SOURCES: Literature from 1970 to February 2002 was identified via 1). general bibliographic databases, that is, MEDLINE and EMBASE, 2). Cochrane Library and relevant specialist register of the Cochrane Collaboration, and 3). checking the reference lists of known primary and review articles. METHODS OF STUDY SELECTION: Studies were selected if the accuracy of dipstick urinalysis techniques in predicting total protein excretion was estimated compared with a reference standard (laboratory estimation of protein excretion). The tests included visually read color-change dipsticks and automated dipstick urinalysis. Study selection, quality assessment, and data abstraction were performed independently and in duplicate. TABULATION, INTEGRATION, AND RESULTS: Data from selected studies were abstracted as 2 x 2 tables comparing the test result with the reference standard. Test accuracy was expressed as likelihood ratios. Summary likelihood ratios were generated as measures of diagnostic accuracy to determine posttest probabilities. The electronic search produced 1543 citations. After independent review of published articles, a total of 34 articles was obtained for further scrutiny, and 7 studies were considered eligible for inclusion in the review. The 6 studies evaluating visual dipstick urinalysis produced a pooled positive likelihood ratio of 3.48 (95% confidence interval 1.66, 7.27) and a pooled negative likelihood ratio of 0.6 (95% confidence interval 0.45, 0.8) for predicting 300 mg/24-hour proteinuria at the 1+ or greater threshold. CONCLUSION: The accuracy of dipstick urinalysis with a 1+ threshold in the prediction of significant proteinuria is poor and therefore of limited usefulness to the clinician. Accuracy may be improved at higher thresholds (greater than 1+ proteinuria), but available data are sparse and of poor methodological quality. Therefore, it is not possible to make meaningful inferences about accuracy at higher urine dipstick thresholds. There is an urgent need for research in this area of common obstetric practice.

Female↗

Ossification of femoral head: normal sonographic standards.

The aim of the study was to establish normal reference standards for the appearance of the femoral head ossification center according to age, sex, and gestational age. Sonographic examination of the hip was performed in 1,800 healthy Indian and Israeli infants (900 each) aged 2 to 24 weeks. There were an equal number of boys and girls. The ossification center was noted at 2 weeks of life in the Israeli infants and at 8 weeks in the Indian infants. However, from 10 to 16 weeks, it was noted in 81% or more of the Indian infants but only 22% to 74% of the Israeli ones. In both groups, between 20 and 24 weeks of age, it was noted in more than 90% of the infants. An association was found between gestational age at birth and chronologic age of appearance of the femoral head ossification center, but only among the Israeli infants. There were no differences between genders. Knowledge of the normal sonographic appearance of the femoral head ossification center by age and ethnicity will help clinicians in the diagnosis of hip disorders.

Ethnicity↗

Comparison of the SonoSite and Acuson 128/XP10 ultrasound machines in the 'bed-side' assessment of the post liver transplant patient.

Hepatic artery thrombosis after liver transplant is associated with biliary sepsis and irretrievable loss of the graft. Early identification of hepatic artery thrombosis, using a 'high-specification' ultrasound machine incorporating spectral Doppler, is crucial to patient management in the postoperative period with portable ultrasound as the first line of investigation for evaluation of the hepatic artery. We evaluated the efficacy of the SonoSite portable ultrasound machine, which uses power Doppler only, in the evaluation of the post transplant hepatic artery. An Acuson 128/XP10 ultrasound machine was used as the comparison 'reference-standard' with identification of the hepatic artery by both colour and spectral Doppler trace. The SonoSite accurately identified the hepatic artery in 88.4% of patients with power Doppler. The SonoSite was easier to transport and manage at the bedside leading to considerable time saving. In 11.6% of patients a repeat ultrasound using the 'reference-standard' machine would be necessary.

Female↗

Accuracy of magnetic resonance imaging for the diagnosis of multiple sclerosis: systematic review.

OBJECTIVE: To determine the accuracy of magnetic resonance imaging criteria for the early diagnosis of multiple sclerosis in patients with suspected disease. DESIGN: Systematic review. DATA SOURCES: 12 electronic databases, citation searches, and reference lists of included studies. Review methods Studies on accuracy of diagnosis that compared magnetic resonance imaging, or diagnostic criteria incorporating such imaging, to a reference standard for the diagnosis of multiple sclerosis. RESULTS: 29 studies (18 cohort studies, 11 other designs) were included. On average, studies of other designs (mainly diagnostic case-control studies) produced higher estimated diagnostic odds ratios than did cohort studies. Among 15 studies of higher methodological quality (cohort design, clinical follow-up as reference standard), those with longer follow-up produced higher estimates of specificity and lower estimates of sensitivity. Only two such studies followed patients for more than 10 years. Even in the presence of many lesions (> 10 or > 8), magnetic resonance imaging could not accurately rule multiple sclerosis in (likelihood ratio of a positive test result 3.0 and 2.0, respectively). Similarly, the absence of lesions was of limited utility in ruling out a diagnosis of multiple sclerosis (likelihood ratio of a negative test result 0.1 and 0.5). CONCLUSIONS: Many evaluations of the accuracy of magnetic resonance imaging for the early detection of multiple sclerosis have produced inflated estimates of test performance owing to methodological weaknesses. Use of magnetic resonance imaging to confirm multiple sclerosis on the basis of a single attack of neurological dysfunction may lead to over-diagnosis and over-treatment.

Case-Control Studies↗

Ascertainment of intimate partner violence in women seeking legal protection.

BACKGROUND: Brief questions are necessary for identification of women seeking emergency professional services for intimate partner violence (IPV), and for initiating dialogue with women presenting for care who have previously reported abuse. We compare three questions that inquire about physical and psychological abuse to the Conflict Tactics Scale, version 2 (CTS-2) in a cohort of women seeking legal protection for IPV. METHODS: A total of 448 urban women reporting IPV to police or the court system completed surveys at 8 weeks (baseline), and 5 and 10 months after the incident to assess IPV. Sensitivity and specificity of brief questions on physical assault/abuse (one question) and psychological abuse (two questions) were assessed at baseline and in the periods between baseline and follow-up, using items from the CTS-2 reflecting minor and severe physical and psychological IPV as reference standards. RESULTS: Compared to the CTS-2 severe items, the physical abuse question at baseline detected 93% of abused women, and the two psychological abuse questions 94%. Sensitivity varied at follow-up (74% to 95% for physical, and 89% to 90% psychological), but remained higher when the severe versus minor CTS-2 items were reference standards. Specificity was reasonable for the physical question compared to the severe CTS-2 section (77% to 95%), but was more varied for the psychological questions (29% to 74%). CONCLUSIONS: Three brief questions reasonably identified women who experienced severe IPV and sought legal protection. The low specificity of the psychological questions suggests that women's abuse experience may not fit within the CTS-2 framework. The three questions should be considered for further testing in real-world settings as a tool for initiating conversation with women about abuse.

Adult↗

Comparison of estimates and calculations of risk of coronary heart disease by doctors and nurses using different calculation tools in general practice: cross sectional study.

OBJECTIVE: To assess the effect of using different risk calculation tools on how general practitioners and practice nurses evaluate the risk of coronary heart disease with clinical data routinely available in patients' records. DESIGN: Subjective estimates of the risk of coronary heart disease and results of four different methods of calculation of risk were compared with each other and a reference standard that had been calculated with the Framingham equation; calculations were based on a sample of patients' records, randomly selected from groups at risk of coronary heart disease. SETTING: General practices in central England. PARTICIPANTS: 18 general practitioners and 18 practice nurses. MAIN OUTCOME MEASURES: Agreement of results of risk estimation and risk calculation with reference calculation; agreement of general practitioners with practice nurses; sensitivity and specificity of the different methods of risk calculation to detect patients at high or low risk of coronary heart disease. RESULTS: Only a minority of patients' records contained all of the risk factors required for the formal calculation of the risk of coronary heart disease (concentrations of high density lipoprotein (HDL) cholesterol were present in only 21%). Agreement of risk calculations with the reference standard was moderate (kappa=0.33-0.65 for practice nurses and 0.33 to 0.65 for general practitioners, depending on calculation tool), showing a trend for underestimation of risk. Moderate agreement was seen between the risks calculated by general practitioners and practice nurses for the same patients (kappa=0.47 to 0.58). The British charts gave the most sensitive results for risk of coronary heart disease (practice nurses 79%, general practitioners 80%), and it also gave the most specific results for practice nurses (100%), whereas the Sheffield table was the most specific method for general practitioners (89%). CONCLUSIONS: Routine calculation of the risk of coronary heart disease in primary care is hampered by poor availability of data on risk factors. General practitioners and practice nurses are able to evaluate the risk of coronary heart disease with only moderate accuracy. Data about risk factors need to be collected systematically, to allow the use of the most appropriate calculation tools.

Community Health Nursing↗

Recent developments in food-matrix Reference Materials at NIST.

Since 1996, the National Institute of Standards and Technology (NIST) has developed several food-matrix Standard Reference Materials (SRMs) characterized for nutrient concentrations. These include SRM 1544 Fatty Acids and Cholesterol in a Frozen Diet Composite, SRM 1546 Meat Homogenate, SRM 1548a Typical Diet, SRM 1566b Oyster Tissue, SRM 1846 Infant Formula, and SRM 2383 Baby Food Composite. Three additional materials--SRM 1946 Lake Superior Fish Tissue, SRM 2384 Baking Chocolate, and SRM 2385 Spinach--are in preparation. NIST also recently assigned values for proximate (fat, protein, etc.), individual fatty acid, and total dietary fiber concentrations in a number of existing SRMs and reference materials (RMs) that previously had values assigned for their elemental composition. NIST has used several modes for assignment of analyte concentrations in the food-matrix RMs, including the use of data provided by collaborating laboratories, alone and in combination with NIST data. The use of data provided by collaborating food industry and contract laboratories for the analysis of food-matrix RMs has enabled NIST to provide assigned values for many analytes that NIST does not have the resources or analytical expertise to measure.

Food Analysis↗