Ethnic and gender differences in the management of type 2 diabetes: a cross-sectional study from Norwegian general practice.

BACKGROUND: Ethnic minority groups from Asia and Africa living in Western countries have a higher prevalence of type 2 diabetes (T2DM) than the general population. We aimed to assess ethnic differences in diabetes care by gender. METHODS: Population-based, cross-sectional study identified 10,161 individuals with T2DM cared for by 282 General Practitioners (GP) in Norway. Ethnicity was based on country of birth. Multilevel regression models adjusted for individual and GP factors were applied to evaluate ethnic differences by gender. RESULTS: Diabetes was diagnosed at a younger mean age in all other ethnic groups compared with Westerners (men: 45.9-51.6 years vs. 56.4 years, women: 44.9-53.8 years vs. 59.1 years). Among Westerners mean age at diagnosis was 2.7 years higher in women compared with men, while no gender difference in age at diagnosis was found in any minority group. Daily smoking was most common among Eastern European, South Asian and Middle East/North African men. In both genders, we found no ethnic differences in processes of care (GPs' measurement of HbA1c, blood pressure, LDL-cholesterol, creatinine). The proportion who achieved the HbA1c treatment target was higher in Westerners (men: 62.3%; women: 66.1%), than in ethnic minorities (men 48.2%; women 53.5%). Compared with Western men, the odds ratio (OR) for achieving the target was 0.45 (95% CI 0.27 to 0.73) in Eastern European; 0.67 (0.51 to 0.87) in South Asian and 0.62 (0.43 to 0.88) in Middle Eastern/North African men. Compared with Western women, OR was 0.49 (0.28 to 0.87) in Eastern European and 0.64 (0.47 to 0.86) South Asian women. Compared with Westerners, the blood pressure target was more often achieved in South Asians and Middle Easterners/North Africans in both genders. Small ethnic differences in achieving the LDL-cholesterol treatment target by gender were found. CONCLUSION: Diabetes was diagnosed at a considerably earlier age in both minority men and minority women compared with Westerners. Several minority groups had worse glycaemic control compared with Westerners in both genders, which implies that it is necessary to improve glucose lowering treatment for the minority groups. Smoking cessation advice should particularly be offered to men in most minority groups.

Analytical performance specifications based on how clinicians use laboratory tests. Experiences from a post-analytical external quality assessment programme.

Analytical performance specifications can be based on three different models: the effect of analytical performance on clinical outcome, based on components of biological variation of the measurand or based on state-of-the-art. Models 1 and 3 may to some degree be combined by using case histories presented to a large number of clinicians. The Norwegian Quality Improvement of Primary Care Laboratories (Noklus) has integrated vignettes in its external quality assessment programme since 1991, focusing on typical clinical situations in primary care. Haemoglobin, erythrocyte sedimentation rate (ESR), HbA1c, glucose, u-albumin, creatinine/estimated glomerular filtration rate (eGFR), and Internationl Normalised Ratio (INR) have been evaluated focusing on critical differences in test results, i.e., a change from a previous result that will generate an "action" such as a change in treatment or follow-up of the patient. These critical differences, stated by physicians, can translate into reference change values (RCVs) and assumed analytical performance can be calculated. In general, assessments of RCVs and therefore performance specifications vary both within and between groups of doctors, but with no or minor differences regarding specialisation, age or sex of the general practitioner. In some instances state-of-the-art analytical performance could not meet clinical demands using 95% confidence, whereas clinical demands were met using 80% confidence in nearly all instances. RCVs from vignettes should probably not be used on their own as a basis for setting analytical performance specifications, since clinicians seem "uninformed" regarding important principles. They could rather be used as a background for focus groups of "informed" physicians in discussions of performance specifications tailored to "typical" clinical situations.

Postanalytical external quality assessment of urine albumin in primary health care: an international survey.

BACKGROUND: Microalbuminuria (MA) is recognized as an important risk factor for cardiovascular and renal complications in diabetes. We sought to evaluate how screening for MA is conducted and how urine albumin (UA) results are interpreted in primary care internationally. METHODS: General practitioners (GPs) received a case history-based questionnaire depicting a male type 2 diabetes patient in whom UA testing had not been performed. Questions were related to type of urine sample used for UA testing, need for a repeat test, whether UA testing was performed in the office laboratory, and what changes in UA results were considered clinically important [critical difference (CD)]. Participants received national benchmarking feedback reports. RESULTS: We included 2078 GPs from 9 European countries. Spot urine samples were used most commonly for first time office-based testing, whereas timed collections were used to a larger extent for hospital-based repeat tests. Repeat tests were requested by 45%-77% of GPs if the first test was positive. Four different measurement units were used by 70% of participants in estimating clinically important changes in albumin values. Stated CDs varied considerably among GPs, with similar variations in each country. A median CD of 33% was considered clinically important for both improvement and deterioration in MA, corresponding to an achievable analytical imprecision of 14%, when UA is reported as an albumin/creatinine ratio. CONCLUSIONS: Guidelines on diagnosing MA are followed only partially, and should be made more practicable, addressing issues such as type of samples, measurement units, and repeat tests.

Economic consequences of near-patient test results: the case of tests for the Helicobacter Pylori bacterium in dyspepsia.

We have developed a model for economic evaluation related to the diagnostic accuracy (sensitivity and specificity) of near patient tests used in office laboratories, as opposed to using hospital-based tests. Blood-sample based tests to detect the bacterium Helicobacter Pylori (HP) are useful in diagnosing peptic ulcer, and suitable to illustrate the model. First, general practitioners' initial management plans for a dyspeptic patient are elucidated using a paper vignette survey. Based on survey results, and medical literature, a decision tree is constructed to visualize expected costs and outcomes resulting from using three different HP tests. Tests included are two rapid tests for use in general practice, and one hospital laboratory test for comparison. The tests had different sensitivities and specificities. Then a cost-effectiveness analysis is undertaken from a societal perspective. Finally we use sensitivity analyses to model the decision uncertainty. Estimating for a follow-up period of 120 days, the rapid test with lower sensitivity and specificity than the hospital HP test is cost-effective because the test result is available immediately. Further, in general practice, the rapid test with the highest sensitivity is significantly cost effective compared to the test with the highest specificity when the willingness to pay for each dyspepsia-free day exceeds 42.6 euros. When deciding whether a laboratory analysis should be analyzed in the office laboratory or not, it is important to consider both the diagnostic accuracy of the tests and waiting time for the alternative hospital laboratory result.

Postanalytical external quality assessment of warfarin monitoring in primary healthcare.

BACKGROUND: An increasing number of patients are treated with warfarin worldwide, and many are monitored in general practice, often with office instruments. Bleeding or thromboembolic episodes may be consequences of inadequate treatment. We have therefore examined some important aspects of general practitioners' (GPs') knowledge of warfarin treatment. METHODS: A questionnaire including 2 case histories with familiar indications for warfarin treatment (mechanical heart valve prosthesis and pulmonary embolism) was circulated to 3781 GPs in Norway as a postanalytical quality assessment. RESULTS: A total of 1547 GPs (41%) responded. There were substantial variations among GPs concerning the frequency of international normalized ratio (INR) monitoring, stated therapeutic ranges for arterial (but not venous) indications for anticoagulation therapy, and handling of a moderately high INR result of 5.9. Most GPs estimated an unrealistically high risk of serious bleeding in the latter situation (median, 15%; 10th and 90th percentiles, 4% and 50%, respectively). The critical difference necessary to change the warfarin dose was highly dependent on perceived therapeutic intervals, and about half of the GPs suggested a critical difference of 0.8 INR, which is attainable with office instruments. Sex and age of the GPs, practice size, and availability of an INR instrument in the office laboratory did not influence the results to any substantial degree, as variations within subgroups were similar. CONCLUSIONS: Gross variations in practice were found, especially for aspects of warfarin treatment that lacked uniform guidelines. Evidence-based and practicable recommendations for treatment and monitoring of these patients are still needed.

Results and feasibility of an external quality assessment scheme for self-monitoring of blood glucose.

BACKGROUND: The analytical quality of self-monitoring of blood glucose (SMBG) is not satisfactory, and the need for standardized control routines for SMBG has been underscored. The objective of this study was to investigate whether an external quality assessment scheme (EQAS) designed for office laboratories could improve the quality of SMBG measurements. METHODS: From October 2001 through March 2004, we conducted 6 glucose surveys for diabetes patients and coordinated them with an EQAS for office laboratories. Patients received 2 control samples by post twice a year. They measured each control sample in duplicate in accordance with written instructions, returned the results, and received an assessment of their analytical performance. Participants who got a poor evaluation were followed up by phone and were offered guidance. RESULTS: Participating in an EQA program over a period of 3 years decreased the percentage of poor results among diabetes patients significantly, from 11.2% to 1.9% in the first and last surveys, respectively. Between-participant CVs improved from 5.5% to 3.7% and were comparable to results from office laboratories. It was difficult to sort out factors contributing to quality improvement. CONCLUSIONS: Implementing a traditional EQAS among diabetes patients may improve the analytical quality of SMBG and could be convenient for motivated patients. Further evaluation of the clinical usefulness of implementing such a program is needed, however, and costs as well as limitations of current EQAS for glucose in general should be taken into account.

[Quality assessment of urine dip-slides in primary care]. / Vurdering av urindyppekultur i primaerhelsetjenesten.

BACKGROUND: In Norway, approximately 35% of surgery laboratories use dip-slides to assess bacteriuria. From 2000 to 2004 the Norwegian centre for quality assurance in primary health care (NOKLUS) has evaluated how office laboratories assess urine dip-slides. MATERIAL AND METHODS: Once a year participants receive inoculated and incubated dip-slides to read and report to NOKLUS. Target values are determined from assessments in four large microbiological laboratories. RESULTS: Knowledge of reading dip-slides is insufficient. Only 40% of the participants in the quality assessment program evaluate whether growth is gram-negative or gram-positive, or take into account whether the growth is mono-bacterial or mixed. Many participants send the dip-slide to microbiological laboratories for evaluation whenever growth is significant, also when the growth is mixed. INTERPRETATION: The programme shows that Norwegian office laboratories do not use all the information they can get from the dip-slide. There is a need for guidelines on this topic in general practice.

Between-lot variation in external quality assessment of glucose: clinical importance and effect on participant performance evaluation.

BACKGROUND: External quality assessment schemes (EQAS) are conducted to evaluate user performance (participant assessment) and to assess different methods and instruments (method assessment). The quality of control materials is crucial to achieving these goals. Inconsistencies in between-lot variations detected by use of different control and sample materials may affect EQAS outcomes. METHODS: For the Accu-Chek Sensor, Precision Xtra, Ascensia Elite, and HemoCue 201 glucometers, 3 different lots of glucose strips were used with each instrument. Method assessment results from analysis of capillary blood and 3 control materials were used to calculate between-lot differences. A simulation study was performed to evaluate the effect of between-lot variation on participant assessment results. RESULTS: With the Precision Xtra, the results obtained with EQA control material mirrored those obtained with capillary blood, but for the other instruments, we found between-lot differences of as much as 1.3 mmol/L, which were substantially greater than those found with capillary blood and of clinical importance at decision limits. The simulation study showed an effect on participant assessment results related to the target values, with the percentage of poor results decreasing (38%, 10%, and 4%) with the use of common, method-specific, and lot-specific target values, respectively. CONCLUSIONS: Between-lot variation may influence participant EQA results for participant and method assessments. The clinical relevance of between-lot variation discovered in EQAS using noncommutable control materials should be examined by use of native blood samples.

Postanalytical external quality assessment of blood glucose and hemoglobin A1c: an international survey.

BACKGROUND: Diabetes mellitus (DM) is diagnosed and monitored worldwide by blood glucose (BG) and glycohemoglobin A(1c) (HbA(1c)) testing, respectively. Methods for quality assessment of clinician interpretations of changes in these laboratory results have been developed. This study uses survey responses from general practitioners (GPs) in different countries to investigate possible differences in interpretation of results, as well as the feasibility of performing international postanalytical external quality assessment surveys (P-EQAS). METHODS: GPs recruited from 7 countries received questionnaires requesting interpretation of changes in a potentially diagnostic capillary BG result and an HbA(1c) value obtained during monitoring of a patient with type 2 DM. GPs were asked to estimate clinically significant differences between 2 consecutive laboratory results [critical difference (CD)/reference change value] for both BG and HbA(1c). The CDs reported by GPs were used to calculate the analytical variation (CV(a)), which was taken as the quality specification for analytical imprecision. Participants received national benchmarking feedback reports after the survey. RESULTS: The study included responses from 2538 GPs. CDs in BG results showed the same pattern and were comparable among countries. Calculated median CV(a) values would be possible to attain at 80% confidence but not at the conventional 95% confidence. For HbA(1c), the same pattern was shown across countries, but with lower changes considered true when HbA(1c) increased than when it decreased. Despite the consistent pattern, variations among GPs were considerable in all countries. CONCLUSIONS: Assessments of CDs for BG and HbA(1c) were similar internationally, and quality specifications for these analytes based on clinicians' opinions are therefore interchangeable among countries. International P-EQAS may contribute to a more rational use of laboratory services and clinical guidelines.