| Study | Reason for exclusion |
|---|---|
| Abdel Gadir 1990 | Serial randomisation |
| Abu Hashim 2011b | Participants had CC failure (defined as failure to achieve pregnancy despite successful CC‐induced ovulation for 6 cycles) as opposed to CC resistance |
| Al‐Mizyen 2007 | Randomisation was by cards numbered 1 to 20; even numbers allocated to one group and odd numbers to another group |
| Badawy 2009 | Trial compared methods of drilling only |
| Foroozanfard 2010 | Compared 5 to 10 punctures in each ovary |
| Franz 2016 | Ineligible intervention: transabdominal versus transvaginal laparoscopic ovarian drilling |
| Gadir 1992 | Serial method of randomisation |
| Greenblatt 1993 | RCT comparing drilling by diathermy + Interceed to 1 ovary versus drilling only to the other ovary 1. Unit of randomisation: ovaries, not participants 2. Only outcome is adhesion formation at second‐look laparoscopy |
| Gürgan 1991 | Use of concurrent controls |
| Heylen 1994 | Use of concurrent controls |
| Kamel 2004 | Compared re‐electrocautery with FSH |
| Kandil 2018 | Compares transvaginal ovarian needle drilling with LOD |
| Keckstein 1990 | Non‐randomised controlled trial comparing Nd:YAG laser drilling versus CO2 laser drilling Different duration of follow‐up between the 2 groups (8 versus 18 to 30 months) |
| Kocak 2006 | Ineligible comparisons. LOD was compared with LOD + metformin |
| Lockwood 1995 | Conference abstract only; lack of usable data; we were not able to obtain data after multiple attempts to contact the authors. |
| Malkawi 2005 | Not an RCT |
| Muenstermann 2000 | Randomisation used an 'alternate' allocation method |
| Nasr 2010 | Both groups underwent LOD |
| Rath 2006 | Quasi‐RCT |
| Roy 2018 | Ineligible intervention: LOD by harmonic scalpel versus monopolar drilling needle |
| Salah 2013 | Ineligible intervention: RCT comparing LOD under local anaesthetic versus general anaesthetic |
| Saravelos 1996 | RCT comparing LOD + interceed to 1 ovary versus drilling only to the other ovary Outcome is adhesion formation at second‐look laparoscopy |
| Seyam 2018 | Not an RCT; prospective controlled study |
| Sunj 2013 | Not an RCT; quasi‐random allocation |
| Tabrizi 2005 | RCT comparing 5 versus 10 versus 15 points electrocautery of the ovary |
| Vrbikova 1998 | No interventions of interest |
| Wang 2015 | Excluded due to article being retracted |
| Zeng 2012 | Ineligible intervention: trial comparing needle puncture drainage with unipolar electrocoagulation drilling |
| Zhu 2010 | This trial compared different numbers of coagulation points |
CC: clomiphene citrate; FSH: follicle stimulating hormone; LOD: laparoscopic ovarian drilling; RCT: randomised controlled trial