Study characteristics
| Studies | Setting | Study period | Design | Patients (n) | Mean age | Type of hypospadias | F/U (months) | Reported outcomes | |
| 1 | Mouravas et al (2013) | Greece | March 2008–February 2010 | RCT | Total: 47 TIP: 23 GTIP: 24 | TIP: 3.2 years GTIP: 3.5 years | Glanular to proximal penile hypospadias | 2–5 years (mean 3.2 years) | UCF, MS, GD, meatus appearance, operative time |
| 2 | Helmy et al8 | Egypt | November 2012–November 2013 | RCT | Total: 60 TIP: 30 GTIP: 30 | TIP: 39.1±15 months GTIP: 41.9±16 months | Distal (subcoronal and distal shaft) | 1 year | UCF, MS, GD, operative time, urinary flow rate |
| 3 | Eldeeb et al9 | Egypt | March 2017–December 2018 | RCT | Total: 60 TIP: 30 GTIP: 30 | TIP : 12 (6–24 months) GTIP: 13 (5–24 months)* | Distal penile | 24 months | UCF, MS, urethral stricture, wound or glans disruption, operative time |
| 4 | Sultan et al16 | Egypt | December 2018–June 2020 | RCT | Total: 60 TIP: 30 GTIP: 30 | TIP: 30 months (9–144 months) GTIP : 36 months (12–96 months)* | Primary hypospadias | 6 months | UCF, MS, GD, urine flow rate, overall success |
| 5 | El Shazly et al17 | Egypt | June 2018–June 2019 | RCT | Total: 50 TIP: 25 GTIP: 25 | TIP: 23±14.8 GTIP: 37.8±48.9 | Distal penile | 6 months | Meatal location, meatal shape, urinary stream, erection, UCF, operative time, HOSE score |
| 6 | Changpei et al20 | China | June 2016–June 2018 | RCT | Total: 78 TIP: 39 GTIP: 39 | TIP: 22.92±15.17 GTIP: 20.18±13.51 | Coronal, distal, mid-penile | TIP: 23.54±4.68 GTIP: 24.85±4.37 | UCF, stricture, HOSE score, GD, urine flow rate, operative time |
| 7 | Ahmed et al26 | Egypt | January 2018–July 2019 | RCT | Total: 110 TIP: 55 GTIP: 55 | TIP:33.6±39.4 months GTIP: 23.1±14.6 months | Distal hypospadias | 6 months | UCF, MS, HOSE score |
| 8 | Zeina et al19 | Egypt | January 2017–July 2020 | RCT | Total: 60 TIP: 30 GTIP: 30 | TIP: 12.6±3.64 months GTIP: 11.40±3.10 months (range: 6–18 months) | Distal hypospadias | 3–6 months | UCF, MS, meatal position, operative time, meatal recession, cosmetic appearance, urine flow rate |
| 9 | Mohammed et al18 | Egypt | November 2015–December 2016 | RCT | Total: 42 TIP: 20 GTIP: 21 | Mean age 9 years (range: 2–16 years) | Distal and mid-penile hypospadias | 6–10 months (mean 8 months) | UCF, MS, mean operative time |
| 10 | Patel et al21 | India | 2020–2022 | RCT | Total: 40 TIP: 20 GTIP: 20 | Not mentioned | Glanular, coronal, subcoronal, distal penile without chordee | 2 years | UCF, MS, diverticulum, wound infection, proximal stricture |
We classified all procedures named under Snodgrass, classic Snodgrass and TIPU as TIP and classified the modification of the TIP procedure with grafts as GTIP, DIGU, Snodgraft, grafted Snodgrass and GTAS as GTIP for the purpose of making uniformity of the above-mentioned procedures.
*Median with range.
DIGU, dorsal inlay graft urethroplasty; F/U, follow-up; GD, glans dehiscence; GTIP, grafted TIP; MS, meatal stenosis; RCT, randomized controlled trial; TIP, tubularized incised plate; TIPU, tubularized incised plate urethroplasty; UCF, urethrocutaneous fistula.