Abstract:
: Population screening for diabetes is not undertaken due
to the high costs involved. Simple tools to identify high risk individuals for
confirmatory testing can be cost saving. Objectives: To develop and validate a risk
score for detection of prevalent diabetes among adults in Sri Lanka. Design,
setting and methods: Data were available from a nationally representative sample
of 4246 adults after excluding those with previously diagnosed diabetes. Two
thirds of this sample was randomly selected for the development and remaining
one third for the validation of the score. Factors that were significantly associated
with prevalent diabetes in a univariate analysis [age, body mass index, waist
circumference hypertension, family history, physical inactivity, gestational
diabetes, osmotic symptoms and balanitis in males or vulvitis in females] were
used to derive individual risk scores. Risk scores were generated for individual
factors by multiplying the beta coefficient values obtained in multiple logistic
regression by a uniform factor. A cut off value of the sum of individual scores was
determined using ROC curve analysis as 32. Results: The area under the curve for
prevalent diabetes was 0.78 (CI 0.73-0.82). In the sample 36.3% had a total score
of >32. A risk score of >32 gave a sensitivity, specificity, positive predictive value
and negative predictive value of 75%, 65.5%, 9.7% and 98.2% respectively.
Conclusion: Using this simple and non-invasive risk evaluation tool it was
possible to narrow down the percentage that needed diagnostic testing for diabetes
to 36.3% of this population while detecting 75% of the undiagnosed subjects.
