No abstract

Background: Instruments for self-monitoring of blood glucose (SMBG) are increasingly used by patients with diabetes. The analytical quality of meters in routine use is poorly characterized. Methods: We compared SMBG performance achieved by patients and by a medical laboratory technician. Imprecision was calculated from duplicate measurements, and deviation as the difference between the first measurement and the mean of duplicate laboratory-method results (calibrated with NIST material). Analytical quality for five groups of SMBG instruments was compared with quality specifications for BG measurements. All participants completed a questionnaire assessing both SMBG training and use of the meters. Results: We recruited 159 SMBG users from a hospital outpatient clinic and 263 others from 65 randomly selected general practices (total of 422). Most (two thirds) used insulin. CVs for the five meter types were 7%, 11%, 18%, 18%, and 20% in the hands of patients and 2.5–5.9% for the technician. For three of five meter types, patients’ BG measurements had larger deviations from the laboratory results than did the technician’s results. The technician’s performance could not predict the patients’. No instrument when used by patients (but two operated by the technician) met published quality specifications. The analytical quality of patients’ results was not related to whether they had chosen the instruments on advice from healthcare personnel (one-third of patients), were only self-educated in SMBG (50%), or performed SMBG fewer than seven times/week (62%). Conclusions: The analytical quality of SMBG among patients was poorer than, and could not be predicted from, the performance of the meters in the hands of a technician. We suggest that new instruments be tested in the hands of patients who are trained on meter use in a routine way.

The effect on analytical performance was most pronounced after a rapid shift in the ambient temperature. Therefore patients need to wait at least 15 min for temperature equilibration of affected meters and strips before measuring 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. Betweenparticipant 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

The analytical quality of self-monitoring of blood ORIGINAL ARTICLE