Objectives: To evaluate the implementation of clinical guidelines
for diabetes mellitus in general practice with a specific computer-based
clinical decision support system (CDSS) as part of the intervention.
Methods: Randomized study with health center as unit. General
practice in Sør- and Nord-Trøndelag counties in Norway, 380,000
inhabitants. Seventeen health centers with 24 doctors and 499 patients with
diabetes mellitus were in the intervention group and 12 health centers with 29
doctors and 535 patients were in the control group. Main outcome measures were
group differences in fractions of patients without registrations (process
evaluation) and mean group differences for the same variables (patient outcome
Results: Statistically significant group differences were
experienced for fractions of patients without registration of cigarette
smoking (intervention group, 82.6%; control group 94.5%), body mass index
(78.2% vs. 93.0%), and sufficient registrations for calculation of risk score
for myocardial infarction (91.1% vs. 98.3%); all during 18 months. Large
center variations were shown for all variables. The only statistically
significant group difference was −2.3 mm Hg (95% CI, −3.8,
−0.8) in diastolic blood pressure in favor of the intervention group.
Statistically insignificant differences in favor of the intervention group
were HbA1c, −0.1% (95% CI, −0.4, 0.1), systolic blood pressure,
−1.2 mm Hg (95% CI, −4.4, 2.0). Statistically insignificant
differences in favor of the control group were fractions of smokers, +3.0%
(95% CI, −4.0, 10.0), body mass index, +0.3 kg/m2 (95%
CI, −0.8, 1.4), risk score in female +0.1 (95% CI, −5.1, 5.2), and
risk score in male +2.6 (95% CI, −14.2, 19.5).
Conclusions: Implementation of clinical guidelines for diabetes
mellitus in general practice, by means of a CDSS and several procedures for
implementation, did not result in a clinically significant change in
doctors' behavior or in patient outcome.