Validation of the Dutch guidelines for dual X-ray absorptiometry measurement

BACKGROUND: In Europe, a case-finding strategy for osteoporosis is recommended above widespread population-based screening. However, no universally accepted policy currently exists. In 2005, the Dutch College of General Practitioners published guidelines for GPs to select patients for dual energy X-ray absorptiometry (DXA). AIM: To evaluate the sensitivity, specificity, and predictive value of the Dutch guidelines to select participants with osteoporosis for DXA. DESIGN OF STUDY: Cross-sectional. SETTING: A total of 345 females aged over 50 years (mean age = 62 years, standard deviation [SD] = 8.3) and 99 males over 65 years of age (mean age = 72 years, SD = 5.2) of a Dutch general practice. METHOD: Calculation of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the Dutch case-finding instrument for selecting patients with osteoporosis for DXA measurement. RESULTS: Sensitivity was 19.5%, specificity 85.6%, PPV 18.6%, and NPV 86.6%. CONCLUSION: The Dutch guidelines are unreliable in detecting people at risk for osteoporosis.