Meta-analysis of complication rates of the tubularized incised plate (TIP) repair

Summary Objective To determine overall complication rates of the tubularized incised plate (TIP) repair and assess the effects of technical modifications, length of follow-up and geographical location of reported results. Materials and methods A systematic literature search was undertaken, using Medline and Pubmed, in order to identify relevant articles. Random effects models were used to estimate pooled complication rates. Meta-regression was performed for each outcome by using mixed effects models with type of hypospadias (primary distal, primary proximal and secondary) as predictors. Results Of the 189 articles that were identified, 49 studies (4675 patients) were included in the analysis. Fistula and re-operation rates were significantly higher in secondary repairs (15.5% and 23.3%) compared to primary proximal (10.3% and 12.2%) and primary distal (5.7% and 4.5%) ( P = 0.045 and P 1 year (12.7%). Comparison of geographical location showed that complication rates for all but one variable were significantly lower in North America when compared to Europe and the rest of the world. Mean meatal stenosis rates were 1.8% in North America, 3.4% in Europe and 8.2% in the rest of the world ( P = 0.002). This remained significant in a multivariable model incorporating repair technique and length of follow-up ( P = 0.046). Mean rates of urethral stricture, fistula and re-operation followed a similar pattern ( P = 0.045, P = 0.009 and P