Schattenkirchner 2003.

Methods	RCT; double‐blind; multicentre. Randomisation procedure not described Follow‐up time: 8 days
Participants	Population: 227 participants, mainly from general practices, 85 women, 142 men. Mean age 45.3 (SD ± 10.1) years Setting: 15 centres in Germany, (mainly) general practices, March 2000 to October 2000 Inclusion criteria: age 20 to 65 years; localised, uncomplicated, acute LBP associated with degenerative spinal disorders; participants having pain without analgesic therapy during previous 24 hours; and with a pain intensity score at rest of at least 60 on a 100‐mm VAS Exclusion criteria: suspicion of serious underlying spinal condition (e.g. sciatica), non‐specific back symptoms related to abdominal, pelvic, or thoracic pathology; prior neurological deficits in lower extremities; surgery for LBP; lumbosacral facet syndrome; history of haematological or bleeding disorders; severe cardiac, hepatic, or renal insufficiency; severe hypertension; connective tissue diseases; history of GI ulcer or bleeding; hypersensitivity to aspirin or NSAIDs; alcohol/drug abuse; pregnant/lactating
Interventions	NSAID (i): aceclofenac 100 mg b.i.d., 10 days or until asymptomatic (N = 114) NSAID (ii): diclofenac 75 mg b.i.d., 10 days or until asymptomatic (N = 113)
Outcomes	Mean change in pain score (100‐mm VAS), from baseline, after 8 to 10 days (SD): (i, N = 114) ‐62.4 (24.5); (ii, N = 113) ‐56.8 (22.6); (ITT analysis, N = 227). QBPDS (functional disability score) change (%), from baseline, after 4 days (SD): (i, N = 100) 25.5 (14.8); (ii, N = 105) 20.6 (12.1); (PP analysis, N = 205) Adverse events: (i) 17 participants (14.9%); (ii) 18 participants (15.9%), none withdrew because of AEs
Funding	Funding not mentioned. Sponsor UCB Pharma (developer of aceclofenac)
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation was achieved by the generation of a randomisation list using permutable blocks.
Allocation concealment (selection bias)	Low risk	Each drug package was identified by a unique code number and was delivered to the participant according to the ascending order of their number. Sealed emergency envelopes with identity of the drugs kept in a secure place, to be opened only in case of a medical emergency, to be returned to the sponsor at the end of the trial.
Blinding of participants and personnel (performance bias) All outcomes ‐ participants	Unclear risk	Double‐blind, no double‐dummy
Blinding of participants and personnel (performance bias) All outcomes ‐ careproviders	Low risk	Double‐blind. No person conducting the trial had access to the randomisation list before the study was unblinded.
Blinding of outcome assessment (detection bias) All outcomes ‐ outcome assessors	Unclear risk	Not mentioned
Incomplete outcome data (attrition bias) All outcomes ‐ dropouts	Low risk	Low dropout rate: 4.4% (10/227 withdrew). (i) 6 early cure; (ii) 1 early cure, 2 lack of efficacy, 1 personal reasons
Incomplete outcome data (attrition bias) All outcomes ‐ ITT analysis	Low risk	ITT analysis performed
Selective reporting (reporting bias)	Unclear risk	Study protocol mentioned in manuscript, but not registered
Similarity at baseline characteristics	Unclear risk	According to text, similar baseline characteristics in both treatment groups, but data were not shown, no table 1.
Co‐interventions avoided or similar	Low risk	During the study, participants were not allowed to take any other NSAIDs (except for the study medication), muscle relaxants, benzodiazepines, analgesics, corticosteroids, or coumarinics, or to receive physical or chirotherapy
Compliance acceptable	Unclear risk	Compliance was assessed by the recordings in the participant diaries. (Unused) study medication was not collected.
Timing outcome assessments similar	Low risk	Timing similar
Other bias	Low risk	None