Table 1.

The search strategy used for literature research

• PsychINFO: (caffeine and pupil*).af

• Medline: (caffeine and pupil*).af

o In addition, we implemented the following subject heading-based strategy:

• 1 Pupil/

• 2 (pupil* adj3 (size or enlarge* or large* or dilat* or small or constrict* or contract*)).ti,ab,kw

• 3 pupil*.ti

• 4 1 or 2 or 3

• 5 Caffeine/23720

• 6 coffee/or energy drinks/or tea/

• 7 (caffeine* or coffee or tea or energy drink?).ti,ab,kw

• 8 5 or 6 or 7

• 9 4 and 8

• Embase: (caffeine and pupil*).af

• Cochrane Library: caffeine pupil*