Harte 2007.

Methods	RCT; predetermined randomization table, concealment of allocation through sealed, opaque and sequentially numbered envelopes.
Participants	30 participants (16 in the traction group and 14 in the manual therapy group) with acute or subacute LBP accompanied with radiculopathy. Exclusion in case of previous spinal surgery, co‐existing conditions interventions within the last 3 months. Mean age T) 45.25 years, C) 42.79 years. Duration of complaints: T) 6.5 wk, C) 6 wk.
Interventions	T) Traction: manual therapy (techniques described by Maitland or Cyriax), exercises, advice and motorized lumbar traction for 4‐6 wk, 2‐3 times per wk, 10‐20 min per session, traction force 5‐60 kg. C) Comparison intervention: manual therapy, exercises and advice.
Outcomes	Assessment at discharge, 3 months and 6 months post‐treatment (all measures median (IQR), T vs. C). RMDQ: at discharge: 4 (5.8) vs. 4 (10.3), 3 months: 4.5 (10.8) vs. 1 (10.5), 6 months: 4.5 (15.3) vs. 2.5 (14). MPQ‐PRI: at discharge: 4 (15.3) vs. 12 (16.5), 3 months: 6 (16.5) vs. 6 (21), 6 months: 10 (20.5) vs. 6.5 (21). SF36 PCS: at discharge: 38.5 (16.2) vs. 41.1 (21.1), 3 months: 41.6 (18.6) vs. 43.2 (24), 6 months: 40 (15) vs. 46 (22). SF36 MCS: at discharge: 52 (26.1) vs. 48.3 (25.6), 3 months: 49.5 (25.8) vs. 47.3 (21.3), 6 months: 51.8 (23) vs. 49.8 (19.8).
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Predetermined randomization table.
Allocation concealment (selection bias)	Low risk	Sealed, opaque and sequentially numbered envelopes.
Blinding (performance bias and detection bias) All outcomes ‐ participants	High risk	Participants were not blinded.
Blinding (performance bias and detection bias) All outcomes ‐ providers	High risk	Care providers were not blinded.
Blinding (performance bias and detection bias) All outcomes ‐ outcome assessors	Low risk	Outcome assessors were blinded to treatment group allocation.
Incomplete outcome data (attrition bias) All outcomes ‐ loss to follow‐up	High risk	7 participants were lost to follow‐up (23%).
Incomplete outcome data (attrition bias) All outcomes ‐ intention to treat analysis	Unclear risk	Intention‐to‐treat analysis was used.
Selective reporting (reporting bias)	High risk	Published results did not include all prespecified outcomes: VAS score, improvement and straight leg raising test.
Group similarity at baseline (selection bias)	High risk	Baseline characteristics varied between groups: off work due to LBP, history of episodes, participation in physical activity and presence of neurological signs.
Influence of co‐interventions (performance bias)	Low risk	Participants were not permitted to receive any other type of manual therapy or any additional interventions during the treatment period.
Compliance with interventions (performance bias)	Unclear risk	Not mentioned.
Timing of outcome assessments (detection bias)	Low risk	All important outcome assessments for all intervention groups were measured at the same time.