The Short Form-12 and the measurement of health status in patients with cerebral aneurysms: performance, validity, and reliability

Object. Cerebral aneurysms can affect a patient's health status by rupture and stroke, impingement on neural structures, treatment side effects, or psychological stress. The authors assessed the performance, validity, and reliability of the Short Form-12 (SF-12), a self-administered written survey instrument, to assess health status in patients with cerebral aneurysms. Methods. A cohort of 170 patients with cerebral aneurysms who were seen at a neurosurgery clinic underwent structured interviews including measurement of their health statuses (SF- 12 physical component summary [PCS] and mental component summary [MCS]), functional status (Glasgow Outcome Scale score, modified Rankin Scale score, and Barthel Index), and mental health (Hospital Anxiety and Depression Scale score). The SF-12 scores were compared with US population norms by performing t-tests with unequal variances. The validity of the SF-12 was assessed by comparing the PCS and MCS scores with each patient's functional status and mental health scores by using rank-order methods. Inter-item reliability was assessed using the Cronbach alpha statistic. Patients with cerebral aneurysms had decreased health status PCS and MCS scores when compared with population norms (p < 0.001 for all). A history of subarachnoid hemorrhage (SAH) (p = 0.006) and previous surgical or endovascular treatment (p = 0.047) was associated with worse PCS scores. The validity of the SF-12 was supported by the relationship between the PCS and MCS scores and the patient's functional status and mental health (p < 0.001 for all). The reliability of the SF-12 was documented by the Cronbach alpha statistic (alpha = 0.76). Conclusions. Patients with cerebral aneurysms have a diminished physical and mental health status as measured using the SF-12. The presence of SAH and aneurysm treatment are associated with a worse physical health status. The SF- 12 is a valid and reliable instrument for measuring health status in patients with cerebral aneurysms.