Purpose: To compare three anxiety scales; the anxiety visual analogue scale (VAS), the anxiety component of the Amsterdam preoperative anxiety and information scale (APAIS), and the state portion of the Spielburger state-trait anxiety inventory (STAI), for assessment of preoperative anxiety levels in same day admission patients.
Methods: Patients completed the three anxiety assessment scales both before and after seeing the anesthesiologist preoperatively. The scales used were the STAI, the six-question APAIS, and the VAS. APAIS was further subdivided to assess anxiety about anesthesia (sum A), anxiety about surgery (sum S) and a combined anxiety total (i.e., sum C = sum A + sum S). These scales were compared to one another. Pearson's correlation (pair-wise deletion) was used for validity testing. Cronbach's alpha analysis was used to test internal validity of the various components of the APAIS scale. A correlation co-efficient (r) > or = 0.6 and P < 0.05 were considered significant.
Results: Four hundred and sixty three scale sets were completed by 197 patients. There was significant and positive correlation between VAS and STAI r = 0.64, P < 0.001), VAS and APAIS r = 0.6, P < 0.001), sum C and STAI r = 0.63, P < 0.001) and between VAS and sum C r = 0.61, P < 0.001). Sum C and STAI r value were consistent with repeated administration. Cronbach's alpha-levels for the anxiety components of the APAIS (sum C) and desire for information were 0.84 and 0.77 respectively.
Conclusion: In addition to VAS, the anxiety component of APAIS (sum C) is a promising new practical tool to assess preoperative patient anxiety levels.