The wrinkle severity rating scale - A validation study

Background: Patient satisfaction is the most important outcome in facial aesthetic surgery. However, the need for evidence-based evaluation of aesthetic procedures dictates the use of more objective and quantitative measures of treatment outcome. Objective: The present study was undertaken to validate a new clinical outcome instrument,. the Wrinkle Severity Rating Scale. Methods: Five clinical investigators were presented with 30 photographic images of the lower face and asked to rate nasolabial fold severity on each side using the 5-grade Wrinkle Severity Rating Scale (WSRS). Standardized definitions of the five grades were provided to the investigators in visual (photographic) and descriptive formats. To take into account possible facial asymmetry, nasolabial folds on the left and right sides of the face were rated separately. Assessments were conducted independently and were repeated after greater than or equal to2 weeks. Results: Intra-observer (test-retest) agreement was 68.7% (left side) and 72.7% (right side); weighted kappa coefficients for the left and right sides were 0.77 and 0.81, respectively. Mean inter-observer agreement (internal consistency) was 67.7% (left side) and 72.3% (right side); weighted kappa coefficients for the left and right sides were 0.75 (95% CI 0.70-0.79) and 0.78 (95%,CI 0.72-0.83), respectively. Conclusion: The WSRS is a valid and reliable instrument for quantitative assessment of facial skin folds, with good inter- and intra-observer consistency. By allowing objective and reproducible grading of data, the WSRS should prove a useful clinical tool for assessing the effectiveness of soft-tissue augmentation and other facial contouring procedures.