Table 1 PICOS criteria for inclusion in the systematic review

P

Participants

Adults with three-part and four-part proximal humeral fractures with traumatic origin

I

Intervention

Conservative treatment

C

Control

None

O

Outcomes

Constant score, complications, range of movement

S

Study design

Studies published between 2000–2019, with levels I–IV, patients older than 18 years, at least 15 patients, minimum follow-up 1 year, studies using a fracture classification system (Neer or AO)