Smekal 2009.

Methods	Study design: single‐centre, 2‐group, parallel‐design RCT Duration of the study: April 2003‐November 2005 Protocol was published before recruitment of participants: not reported, but no protocol was published Details of trial registration: not registered Funding sources: none known
Participants	Place of study: tertiary trauma centre from Austria Number of participants assigned: 68 participants (33 surgical; 35 conservative) Number of participants assessed: 60 participants (30 surgical; 30 conservative) Inclusion criteria Aged 18‐65 years Unilateral displaced middle third clavicle fracture with no cortical contact between the main fragments Isolated clavicle fracture Exclusion criteria Fracture of the medial or lateral third of the clavicle Former relevant injuries or additional pathological conditions (acute or chronic) affecting the function of the upper extremity Concomitant injuries Pathological fracture or open fractures Fractures with an associated neurovascular injury Contraindication for surgery in general anaesthesia Nonresident patients Age Surgical group (mean/SD): 35.5/11.8 years Conservative group (mean/SD): 39.8/14.5 years Gender of participants assessed (male/female) Surgical group: 26/4 Conservative group: 26/4 Classification of injury: AO classification
Interventions	Timing of intervention: not specified; however, the study authors reported that surgery was performed within the 1st 3 days after trauma Type of surgical intervention: closed reduction and intramedullary fixation using a TEN ‐ 2.5 mm for men and 2 mm for women Type of conservative intervention: simple sling for 3 weeks Rehabilitation Surgical group: a simple sling was used and participants were encouraged to start with pain‐dependent mobilisation immediately and to discard the sling as soon as possible; load bearing was not recommended before osseous consolidation. Conservative group: after 3 weeks all participants were encouraged to start with pain‐dependent mobilisation and to discard the sling; load bearing was not recommended before osseous consolidation. Any co‐interventions: not reported
Outcomes	Length of follow‐up Follow‐up was 2 years Loss to follow‐up: 8 participants were lost to follow‐up at 2 years Surgical group: 3 participants were lost at 2 years Conservative group: 5 participants were lost at 2 years Primary outcomes Function or disability measured by DASH and Constant score Failure of treatment Secondary outcomes: Adverse events measured by: Long‐term follow‐up: transient neurogenic compromise, telescoping and medial nail protrusion
Notes	When closed reduction failed (13.3% of participants), a short incision was made to reduce the fracture. 25 participants (89.3%) underwent implant removal after a mean time of 23 (6‐120) weeks. We tried unsuccessfully to contact the study authors to obtain further information. Composite adverse events: surgery: implant removal for cutout or irritation (n = 7). Conservative: symptomatic malunion (n = 2); transient neurogenic compromise (n = 3). In Analysis 1.14 we used event rates 7 for surgery and 3 for conservative. Cosmetic result events: not distinguished from adverse events
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	A balanced block randomisation with a block size of 4 was used. By throwing a dice 15 times, a randomisation list with fifteen 4 blocks and therefore 60 treatment options was obtained. Quote: "The assigned treatment options of patients lost to follow‐up were collected and separately put in an envelope in a second box. After using all envelopes from the first box, envelopes were randomly picked from the second box". Comment: it was unclear what lost to follow‐up means; the study authors reported unclear information about the participants who were lost to follow‐up after randomisation.
Allocation concealment (selection bias)	Unclear risk	The assigned treatment options were numbered, sealed within an envelope and given in strict rotation in a first box; assigned treatment options of participants lost to follow‐up were collected and separately put in an envelope in a second box. The envelopes of the second box were probably unsealed.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants and personnel were not blinded.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Outcome assessors were not blinded.
Incomplete outcome data (attrition bias) All outcomes	Low risk	The authors excluded 8 participants who did not complete follow‐up, and an intention‐to‐treat analysis was not performed; however, only 5 participants were lost from the conservative group and 3 from the surgical group.
Selective reporting (reporting bias)	High risk	No baseline data for efficacy outcomes were presented and only P values were reported.
Other bias	High risk	Information on whether baseline was balanced was insufficient as no outcome data were reported for baseline.