Source	Search strategy	Hits received
1. ALOIS (www.medicine.ox.ac.uk/alois)	Advanced search: [Study design: RCT OR CCT] AND [Health condition: Alzheimer OR MCI] AND [Intervention: "vitamin E"] (all dates)	Oct 2014: 11 May 2015: 0 Apr 2016: 0
2. MEDLINE In‐process and other non‐indexed citations and MEDLINE 1950 to present (OvidSP)	1. *Vitamin E/ 2. "vitamin E".ti,ab. 3. "alpha‐tocopherol".ti,ab. 4. or/1‐3 5. Alzheimer*.ti,ab. 6. Alzheimer Disease/ 7. AD.ti,ab. 8. "cognit* impair*".ti,ab. 9. MCI.ti,ab. 10. (AACI or memory or CIND or ARCD or ACMI).ti,ab. 11. ("N‐MCI" or "A‐MCI" or "M‐MCI").ti,ab. 12. (nMCI or aMCI or mMCI).ti,ab. 13. (CDR adj2 "0.5").ab. 14. or/5‐13 15. 4 and 14 16. randomized controlled trial.pt. 17. controlled clinical trial.pt. 18. randomi?ed.ab. 19. placebo.ab. 20. drug therapy.fs. 21. randomly.ab. 22. trial.ab. 23. groups.ab. 24. or/16‐23 25. (animals not (humans and animals)).sh. 26. 24 not 25 27. 15 and 26	Oct 2014: 51 May 2015: 6 Apr 2016: 43
3. EMBASE 1980 to 2011 week 27 (OvidSP)	1. *Vitamin E/ 2. "vitamin E".ti,ab. 3. "alpha‐tocopherol".ti,ab. 4. or/1‐3 5. Alzheimer*.ti,ab. 6. Alzheimer Disease/ 7. AD.ti,ab. 8. "cognit* impair*".ti,ab. 9. MCI.ti,ab. 10. (AACI or memory or CIND or ARCD or ACMI).ti,ab. 11. ("N‐MCI" or "A‐MCI" or "M‐MCI").ti,ab. 12. (nMCI or aMCI or mMCI).ti,ab. 13. (CDR adj2 "0.5").ab. 14. or/5‐13 15. 4 and 14 16. randomi?ed.ab. 17. placebo.ab. 19. trial.ab. 20. groups.ab. 21. randomized controlled trial/ 22. controlled clinical trial/ 23. ("double‐blind*" or "single‐blind*").ti,ab. 24. or/16‐23 25. 15 to 24	Oct 2014: 100 May 2015: 65 Apr 2016: 40
4. PsycINFO 1806 to July week 2 2011 (OvidSP)	1. "vitamin E".ti,ab. 2. "alpha‐tocopherol".ti,ab. 3. Alzheimer*.ti,ab. 4. Alzheimer Disease/ 5. AD.ti,ab. 6. "cognit* impair*".ti,ab. 7. MCI.ti,ab. 8. (AACI or memory or CIND or ARCD or ACMI).ti,ab. 9. ("N‐MCI" or "A‐MCI" or "M‐MCI").ti,ab. 10. (nMCI or aMCI or mMCI).ti,ab. 11. (CDR adj2 "0.5").ab. 12. randomi?ed.ab. 13. placebo.ab. 14. randomly.ab. 15. trial.ab. 16. groups.ab. 17. ("double‐blind*" or "single‐blind*").ti,ab. 18. Clinical Trials/ 19. 1 or 2 20. or/3‐11 21. or/12‐18 22. 19 and 20 and 21	Oct 2014: 10 May 2015: 4 Apr 2016: 0
5. CINAHL (EBSCOhost)	S1 (MM "Vitamin E") S2 TX "vitamin E" S3 TX "alpha‐tocopherol" S4 S1 or S2 or S3 S5 (MH "Alzheimer's Disease") S6 TX AD OR alzheimer* S7 "mild cognitive impairment" S8 TX "cognit* impair*" S9 TX AACI OR memory OR CIND OR ARCD OR ACMI S10 TX MCI S11 TX nMCI OR aMCI OR mMCI S12 S5 or S6 or S7 or S8 or S9 or S10 or S11 S13 S4 and S12 S14 TX random* S15 TX placebo* S16 TX trial S17 TX groups S18 TX RCT OR CCT S19 (MH "Randomized Controlled Trials") S20 S14 or S15 or S16 or S17 or S18 or S19 S21 S13 and S20 S22 EM 2009 S23 EM 2010 S24 EM 2011 S25 S22 or S23 or S24 S26 S21 and S25	Oct 2014: 7 May 2015: 5 Apr 2016: 3
6. ISI Web of Knowledge – all databases [includes: Web of Science (1945 to present); BIOSIS Previews (1926 to present); MEDLINE (1950 to present); Journal Citation Reports]	#1 Topic=(alzheimer* OR AD OR MCI OR memory OR cognitive OR "cognit* impair*") AND Topic=("vitamin e" OR "alpha‐tocopherol") AND Year Published=(2009‐2011) Timespan=All Years #2 Topic=(random* OR placebo* OR "double‐blind*" OR "single‐blind*") Timespan=All Years #3 #2 AND #1 Timespan=All Years	Oct 2014: 91 May 2015: 58 Apr 2016: 54
7. LILACS (BIREME)	vitamin‐e OR alpha‐tocopherol	Oct 2014: 1 May 2015: 0 Apr 2016: 0
8. CENTRAL (the Cochrane Library) (Issue 4 of 4, Oct 2010)	#1 “vitamin e” #2 “alpha‐tocopherol” #3 (#1 OR #2) #4 MeSH descriptor Vitamin E, this term only #5 (#3 OR #4) #6 alzheimer* OR AD OR “cognit* impair*” OR MCI #7 (#5 AND #6), from 2011 to 2012	Oct 2014: 33 May 2015: 15 Apr 2016: 0
9. Clinicaltrials.gov (www.clinicaltrials.gov)	Interventional Studies | alzheimer OR alzheimer's OR alzheimers OR MCI OR cognitive OR cognition OR memory | vitamin E OR alpha‐tocopherol | received from 01/01/2011 to 07/15/2012	Oct 2014: 1 May 2015: 2 Apr 2016: 1
10. ICTRP Search Portal (apps.who.int/trialsearch) (includes: Australian New Zealand Clinical Trials Registry; ClinicalTrilas.gov; ISRCTN; Chinese Clinical Trial Registry; Clinical Trials Registry – India; Clinical Research Information Service – Republic of Korea; German Clinical Trials Register; Iranian Registry of Clinical Trials; Japan Primary Registries Network; Pan African Clinical Trial Registry; Sri Lanka Clinical Trials Registry; The Netherlands National Trial Register)	Interventional Studies | alzheimer OR alzheimer's OR alzheimers OR MCI OR cognitive OR cognition OR memory | vitamin E OR alpha‐tocopherol | received from 01/07/2011 to 15/07/2012	Oct 2014: 14 May 2015: 4 Apr 2016: 1
TOTAL before de‐duplication		Oct 2014: 321 May 2015: 159 Apr 2016: 142
TOTAL after de‐duplication and first assessment		Oct 2014: 41 May 2015: 8 Apr 2016: 8