| Study | Reason for exclusion |
|---|---|
| Alekseeva 2000 | Study not randomised |
| Baleztena 2015 | No relevant outcomes measured |
| Belch 1988 | No relevant outcomes measured |
| Belluzzi 1996 | Authors confirmed no relevant outcomes measured |
| Berthoux 1992 | Participants not adult humans, or participants unwell at baseline |
| Borchgrevink 1966 | Mean duration of intervention 10 months (range 3 to 16 months) |
| Busnach 1998 | Participants not adult humans, or participants unwell at baseline |
| CANN 2015 | Intervention is multifactorial (FA/flavanoid blend) |
| Cappelli 1997 | Participants not adult humans, or participants unwell at baseline |
| CARES 2015 | Multisupplement intervention |
| Cheng 1990a | No appropriate control group |
| Cheng 1990b | No appropriate control group |
| Clark 1993 | No relevant outcomes measured |
| Clark 1994 | Participants not adult humans, or participants unwell at baseline |
| Clark 2001 | Participants not adult humans, or participants unwell at baseline |
| Clausen 1989 | Multifactorial intervention (cannot separate effects of omega‐3 fats from those of other dietary, behavioural or drug interventions) |
| Diskin 1990 | No omega‐3 supplementation or dietary advice |
| Donadio 1994 | Participants not adult humans, or participants unwell at baseline |
| Doyle 2001 | Multifactorial intervention (cannot separate effects of omega‐3 fats from those of other dietary, behavioural or drug interventions) |
| Dry 1991 | No relevant outcomes measured |
| Ezaki 1999 | Study not randomised |
| Feher 2005 | Intervention is multifactorial (omega 3 given with coenzyme Q and other compounds vs placebo) |
| FISH 2012 | No clinical outcomes collected (confirmed by corresponding author, 30 November 2016) |
| Fonolla 2009 | Intervention was milk enriched with EPA and DHA but also other vitamins and minerals ‐ multifactorial dietary intervention |
| Fonolla‐Joya 2016 | Intervention was milk enriched with EPA and DHA but also other vitamins and minerals ‐ multifactorial dietary intervention |
| Franzen 1989 | Study not randomised |
| Galarraga 2008 | 9‐month intervention period |
| Gapparova 2000 | Study not randomised |
| Gazso 1992 | No omega‐3 supplementation or dietary advice |
| Geusens 1994 | No relevant outcomes measured |
| Gogos 1998 | Participants not adult humans, or participants unwell at baseline |
| Greatrex 2000 | Study not randomised |
| Griffin 1999 | Study not randomised |
| Hamazaki 1984 | Participants not adult humans, or participants unwell at baseline |
| Hansen 1996 | Multi‐factorial intervention (cannot separate effects of omega‐3 fats from those of other dietary, behavioural or drug interventions) |
| Harris 1991 | No appropriate control group |
| Hashimoto 2012 | No relevant outcomes measured |
| Hashimoto 2016 | No relevant outcomes measured |
| Hawthorne 1992 | Authors confirmed no relevant outcomes measured |
| HEARTS 2015 | Intervention included intensive behavioural changes including exercise and nutrition counselling geared towards weight loss |
| Hogg 1995 | Participants not adult humans, or participants unwell at baseline |
| HOPE epilepsy 2012 | Trial recruitment was suspended due to lack of funding |
| Huang 1996 | No relevant outcomes measured |
| Huang 2008 | Intervention was 9 months and no relevant outcomes |
| ISRCTN38354847 | The proposed one‐year study was never conducted |
| Junker 1990 | Follow‐up not at least a year |
| Kachorovskii 1977 | No omega‐3 supplementation or dietary advice |
| Kanorskii 2007 | LCn3 compared to sotalol (group 1), sotalol & perindopril (group 2), sotalol, perindopril & rosuvastatin (group 3), so no useful control group |
| Karlsson 1998 | Multifactorial intervention (cannot separate effects of omega‐3 fats from those of other dietary, behavioural or drug interventions) |
| Kaul 1992 | Intervention duration 6 months |
| Khan 2003 | Intervention was 8 months |
| Konya 2000 | Study not randomised |
| Kremer 1995 | < 1 year duration |
| Kruger 1998 | No relevant outcomes measured |
| Kurabayashi 2000 | < 1 year duration |
| Lau 1993 | Authors confirmed no relevant outcomes |
| Leaf 1995 | Study not randomised |
| Lee 2010 | Authors confirmed no relevant outcomes measured |
| Leng 1998 | Multifactorial intervention (cannot separate effects of omega‐3 fats from those of other dietary, behavioural or drug interventions) |
| LipiDiDiet 2016 | Multifactorial dietary intervention that included omega 3 fats but many other nutrition components |
| Loeschke 1996 | No relevant outcomes measured |
| LUTEGA 2013 | Multisupplement intervention |
| Lyon Diet Heart 1994 | Multifactorial intervention (cannot separate effects of omega‐3 fats from those of other dietary interventions) |
| Maachi 1995 | Participants not adult humans, or participants unwell at baseline |
| Macsai 2008 | No relevant outcomes measured |
| Mansel 1990 | Not an omega‐3 intervention |
| Mantzaris 1996 | No relevant outcomes measured |
| Mate‐Jimenez 1991 | Authors confirmed no relevant outcomes |
| Matsuyama 2005 | Publication retracted (fraudulent) |
| Middleton 2002 | Unbalanced intervention as the intervention arm contains additional GLA |
| MoodFOOD 2016 | Multisupplement intervention |
| NAYAB 2017 | No planned relevant outcomes. Follow‐up < 12 months |
| NCT01235533 | 48 weeks intervention planned in trials register entry |
| NU‐AGE 2014 | Multifactorial dietary intervention |
| NutriMEMO 2014 | Mutlisupplement intervention |
| OFAMS 2012 | No relevant outcomes measured |
| Okuda 1996 | No appropriate control group |
| OLIVE 1998 | Study was not funded and did not achieve full recruitment (info provided by co‐author) |
| Oslo DIET HEART 1970 | Multifactorial intervention (cannot separate effects of omega‐3 fats from those of other dietary, behavioural or drug interventions) |
| Pogozheva 1997 | Study not randomised |
| Pogozheva 2000 | Study not randomised |
| Puri 2008 | Authors confirmed no relevant outcomes |
| Quazi 1994 | Study not randomised, < 1 year intervention |
| Sacks 1994 | < 1 year intervention |
| Saynor 1988 | Study not randomised |
| Saynor 1992 | No appropriate control group |
| Selvais 1995 | Intervention was < 1 year |
| Shimizu 1995 | Authors confirmed no relevant outcomes |
| Singh 1992 | Expressions of concern issued by the BMJ and The Lancet regarding research by this first author (BMJ 2005; Horton 2005) |
| Singh 1997a | Expressions of concern issued by theBMJ and The Lancet regarding research by this first author (BMJ 2005; Horton 2005) |
| Singh 1997b | Expressions of concern issued by the BMJ and The Lancet regarding research by this first author (BMJ 2005; Horton 2005) |
| Singh 2002 | Expressions of concern issued by the BMJ and The Lancet regarding research by this first author (BMJ 2005; Horton 2005) |
| Tariq 1989 | Participants not adult humans, or participants unwell at baseline and intervention is < 1 year |
| Terano 1999 | Authors confirmed no relevant outcomes during trial |
| Tomer 2001 | No relevant outcomes. Measured lipids but unclear baseline and endpoint is probably 4 weeks |
| Torjesen 1997 | Multifactorial intervention (cannot separate effects of omega‐3 fats from those of other dietary, behavioural or drug interventions) |
| VSDR 2015 | The supplement (Nutrof Omega) contained DHA, Vit C, E, B1, B2, B3, B6, B9, B12, Zn, Mn, Se, Cu, lutein and zeaxanthin (multifactorial dietary intervention) |
| Wheaton 2010 | Participants were not a minimum of 18 years old |
| Yasui 2001 | No appropriate control group |
| Zinger 1987 | Study not randomised |
DHA: docosahexaenoic acid; EPA: eicosapentaenoic acid; FA: fatty acid; GLA: gamma linolenic acid.