The effect of DXA scanning on clinical decision making by general practitioners: a randomized, prospective trial of direct access versus referral to a hospital consultant

The objective of the study was to assess the impact of direct access DXA scanning (DADS) upon GPs' management decisions in patients considered to be at risk of osteoporosis. It was designed as a randomized, prospective, parallel group trial, set within the primary care environment and a university teaching hospital. The participants were 330 patients aged 31 to 89 years from 18 general practices in Edinburgh. Patients were randomized to either DADS or to the current system of specialist referral (controls). The primary outcome measure was frequency of change of management after DXA scanning. Secondary outcome measures were: change in health status, adherence to therapy, clinical events and resource use at one-year follow-up. The primary outcome was that 60% each of DADS patients (98/165) and controls (99/165) had changes in management following DXA scanning. In 30% of patients (12/41) in whom GPs had proposed changing management even in the absence of a scan, different therapy was chosen after the scan (no difference between DADS and control groups). There was an improvement in health utility (p =0.014 for both groups combined), differing slightly between the two groups even after age correction (p =0.014). 68% of the DADS group and 70% of controls were adherent to therapy after one year. In terms of clinical events, at one year there was one major adverse event (control group patient), 5 new fractures in the DADS group and 3 in controls - there were no hip fractures in this study. With regard to resource use, there were 24 referrals to hospital specialist after DXA scanning among the DADS group, vs 12 among controls (p < 0.05). The total number of visits to health professionals was 525 in DADS and 585 in controls (p=ns); mean waiting time from randomization to receipt of report/clinic letter was 4 weeks for DADS vs 13 weeks for controls(p < 0.0001). In conclusion, DXA scanning resulted in management change in at least 60% of cases. Direct access does not result in a clinical outcome significantly different from a consultant led service, and is more economically efficient than the current model of hospital referral.