| Study | Reason for exclusion |
|---|---|
| Abraham 1987 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Abrams 1967 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Agarwal 1985 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Arato 1980 | Not RCT |
| Bagadia 1981 | ECT combined with other interventions, but other interventions were not the same between groups: ECT + placebo versus simulated ECT + imipramine |
| Bagadia 1988 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Baker 1958 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Baker 1960 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Baker 1960a | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Bhatia 1987 | Not RCT |
| Brandon 1985 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Brill 1959 | Not whole population had schizophrenia or related disorder. |
| Chatterjee 1980 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| ChiCTR‐OPC‐14005339 | Not RCT |
| d'Elia 1970 | Not whole population had schizophrenia or related disorder. |
| Doongaji 1973 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| El Islam 1970 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Gan 2017 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Gander 1967 | Not whole population had schizophrenia or related disorder. |
| Gangadhar 2000 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Girish 2003 | Not whole population had schizophrenia or related disorder. |
| Hargreaves 1972 | Not whole population had schizophrenia or related disorder. |
| He 2001 | ECT used in both groups: ECT advantage side versus non‐advantage side. |
| Heath 1964 | Not RCT |
| Janakiramaiah 1981 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Janakiramaiah 1982 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Krystal 1993 | Not whole population had schizophrenia or related disorder. |
| Laurell 1970 | Not whole population had schizophrenia or related disorder. |
| Laurell 1970a | Not whole population had schizophrenia or related disorder. |
| Marjerrison 1975 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Miller 1953 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Naidoo 1956 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Natani 1983 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| NCT02159001 | ECT used in both groups: ECT treatment right after recruitment versus ECT after 4‐week period. |
| Rami 2008 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Reichert 1976 | Not whole population had schizophrenia or related disorder. |
| Sarkar 1994 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Small 1968 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Smith 1967 | Not RCT |
| Stenback 1957 | ECT used in both groups: usual ECT versus block ECT. |
| Swoboda 2001 | Not RCT |
| Taylor 1980 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Ukpong 2002 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Ulett 1956 | Not whole population had schizophrenia or related disorder. |
| Ungvari 1981 | Language other than English or Chinese |
| Wessels 1971 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Xue 1985 | The participants had schizophrenia, but not with a diagnosis of treatment‐resistant. |
| Zadeh 2006 | Language other than English or Chinese |
| Zhou 2003 | Not RCT |
ECT: electroconvulsive therapy; RCT: randomised controlled trial