The Smile Index: Part 2. A Simple, Prognostic Severity Scale for Unilateral Cleft Lip

There is no universally accepted classification system for unilateral cleft lip that objectively quantifies the spectrum of disease, making it difficult to evaluate postoperative outcomes in the context of preoperative severity. Anthropometric measurements and photographs were prospectively collected from unilateral cleft lip patients in Morocco, Bolivia, Vietnam, and Madagascar. Columellar angle, cleft width, nostril widths, vertical lip heights, and horizontal vermillion lengths were measured preoperatively and postoperatively. "Unacceptable" postoperative outcomes were defined as those with a cleft-side/non-cleft-side vertical lip height discrepancy greater than 3 mm, based on previous sociologic and cleft outcome studies. Of the 147 patients studied, 22 had unacceptable outcomes. Univariate logistic and multivariate logistic stepwise models showed that among preoperative characteristics, cleft width ratio (preoperative cleft width divided by commissure width) was the most significant predictor for unacceptable outcomes, controlling for surgeon experience. Cleft width ratio was normally distributed. Two severity categories were created based on iterative data and regression analysis: "severe" (cleft width ratio >0.5) and "not-severe" (cleft width ratio