Assessment of Preoperative and Postoperative Anxiety: A Comparison of Two Measures in Elective Major Surgery Patients.

Background: Research on measurement of anxiety in patients booked for surgery in Nigeria is sparse, even though heightened anxiety levels in such patients is commonly observed. Aims: The aim of the study presented here was to compare two well established standard measures of anxiety, the Visual Analogue Scale(VAS) and the State Version of the State Trait Anxiety Inventory (STAI), in the measurement of anxiety in patients awaiting elective major surgery. Methods: Subjects booked for elective major surgery were consecutively recruited from the general surgery, orthopaedic sugery and gynaecology clinics of Wesley Guild Hospital, Ilesa, Osun state, Nigeria. A repeated measures design was used for the study.The VAS and STAI Scales were administered on the subjects the night before surgery and daily for each of the seven post operative days. Results:The VAS compared favourably with the STAI as a measure of anxiety in these patients especially in the post operative period. The pearson correlation coefficients, r, (VAS vs STAI) ranged from .29 to .55) demonstrating moderate concurrent validity in the measures. Analysis of scores for the two instruments using repeated measures ANOVA yielded equivalent results. Conclusion: The one-item VAS is a useful clinical tool for measuring anxiety in patients awaiting surgery. For some users it may require more than one administration to achieve mastery, however it compares favourably with the STAI in anxiety measurement. Setting up preoperative counseling clinics for patients booked for elective surgery may be useful in reducing preoperative anxiety. Key Words: Preoperative, postoperative, anxiety, elective surgery.