Study	Reason for exclusion
Angioli 2006	This study was evaluated as a non‐comparable controlled clinical trial. NAC followed by IDS was selectively given to the women based on initial laparoscopic findings of inoperability.
Chan 2003	This study was evaluated as an uncontrolled clinical trial. NAC was given to the women without a control group. The women were selected by their inoperability based on CT scan without primary operation being attempted. Either histology or only cytology was allowed for a pathologic diagnosis of ovarian cancer.
Dutta 2005	This was an RCT of ovarian cancer patients to have either 3 cycles of NAC followed by IDS and further chemotherapy versus 6 cycles of NAC before surgery. Main objective was to study proapoptotic and antiapoptotic proteins in ovarian cancer tissue without survival outcome evaluation.
Evdokimova 1982	This was an RCT comparing survival of women with ovarian carcinoma who had NAC/IDS versus conventional treatment of surgery then chemotherapy. However, those without ascites were selected to have primary surgery followed by chemotherapy while those with ascites had either NAC/IDS or conventional treatment.
Fuso 2006	This uncontrolled prospective study was to assess the feasibility of triple chemotherapy composed of gemcitabine, carboplatin, and paclitaxel as first‐line drugs in advanced ovarian cancer. The women were selectively assigned to have two different types of treatment. After laparoscopic biopsy in all participants, those who were judged to be operable underwent primary surgery followed by chemotherapy, while the inoperable women were given NAC followed by IDS. However, few who had primary surgery also had IDS.
Giannopoulos 2006	This study was evaluated as a non‐comparable controlled clinical trial. NAC and IDS was selectively given to the women who were deemed to be inoperable based on CT scan and initial laparoscopic findings. Either histology or cytology was allowed for a pathologic diagnosis of ovarian cancer.
Ikeba 2004	This study was evaluated as an uncontrolled clinical trial. NAC was given to all, without a control group.
Kuhn 2001	This study was evaluated as a non‐comparable controlled clinical trial. NAC was selectively given to women in poor general health for primary surgery. The control group consisted of those who did not agree to the study protocol or were ineligible for treatment for psychological reasons.
Kumar 2009	This RCT allowed either histologic or cytologic diagnosis. NAC was given to the study arm without an attempt to perform a PDS.
Lee 2006	This study was evaluated as a non‐comparable controlled clinical trial. NAC was selectively given to those who agreed to undergo the NAC treatment protocol. NAC cycles ranged from three to six. Some women had secondary surgery which was not in an interval setting.
Liu 2004	This RCT was considered as ineligible because NAC was given only for one cycle via intra‐arterial route before the IDS.
Madhuri 2014	RCT comparing the efficacy of neutral argon plasma to standard surgery during PDS or IDS
Matulonis 2009	This prospective study was a non‐randomised study. The women aged 75 ‐ 86 years with stage II ‐ IV disease to have PDS followed by adjuvant chemotherapy or to have NAC if they had poor performance status or inoperable metastatic disease. All five women who had NAC were not able to undergo surgery.
Onda 2009	This was a prospective single arm study to evaluate the role of diagnostic laparoscopy in those with a diagnosis of Mullerian carcinoma.
Onda 2014	This RCT compared PDS or NAC then IDS followed more cycles of chemotherapy. IDS was performed in both arms: 31.3% in the PDS arm and 86.8% in the IDS arm.
Park‐Simon 2006	This RCT compared survivals of ovarian cancer patients who had ascites > 500 cc who were given NAC for either two versus three cycles, but followed by IDS in both arms.
Polcher 2009	This RCT randomised women with ascites > 500 cc to have two or three cycles of NAC without an attempt to do PDS.
Recchia 2001	This study was evaluated as an uncontrolled clinical trial. NAC was given to all without a control group. Either histology or only cytology was allowed for a pathologic diagnosis of ovarian cancer.
Solomon 1988	This study was presented in conjunction with the prior RCT comparing combination versus sequential chlorambucil and cisplatin. IDS in this study was selectively performed only in the subset of women who had not been debulked at primary surgery. Second‐look surgery or surgical re‐exploration were also performed on those with clinical complete remission or on those with complications requiring surgery, respectively.
Tiersten 2009	This was a prospective single arm study when the women must have had no aggressive PDS before receiving intraperitoneal chemotherapy followed by surgery.
Vergote 2010	This RCT compared the role of PDS followed by adjuvant chemotherapy in the control arm with NAC before IDS followed by additional chemotherapy in the study arm. However, IDS was also allowed in the PDS arm too, at the discretion of the physician. Furthermore, either histologic or cytologic diagnosis (with tumour marker and imaging criteria to exclude cancers of other non‐Mullerian origins) was allowed.

IDS: interval debulking surgery
 NAC: neoadjuvant chemotherapy
 RCT: randomised controlled trial