Hakkinen 2005.

Methods	Randomly assigned
Participants	126 patients included two months after their first lumbar disc surgery and not pain free (VAS > 10 mm)
Interventions	(I) Home exercise programme after one instruction session for 12 months. Instructions for stretching and stabilisation exercises, instructed to stretch three times AND strength training, instructed to perform two series of exercises twice a week (C) Home exercise programme after one instruction session for 12 months. Instructions for stretching and stabilisation exercises, instructed to stretch three times
Outcomes	At 12 months' follow‐up: improvement in back pain (100‐mm VAS): (I) 4 mm (IQR: ‐11 to 5) versus (C) 1 mm (IQR : ‐7 to 9); leg pain (100‐mm VAS): (I) ‐2 (IQR: ‐7 to 7) versus (C) ‐2 (IQR: ‐7 to 3). Improvement in disability (ODI) (I): 3 mm (IQR: ‐6 to 1) versus (C): ‐2 (‐5 to 1)
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Randomly assigned
Allocation concealment (selection bias)	Unclear risk	Unclear from text
Blinding (performance bias and detection bias) All outcomes ‐ patients?	Unclear risk	Unclear from text
Blinding (performance bias and detection bias) All outcomes ‐ care providers?	Unclear risk	Unclear from text
Blinding (performance bias and detection bias) All outcomes ‐ outcome assessors?	Unclear risk	Unclear from text
Incomplete outcome data (attrition bias) All outcomes ‐ drop‐outs?	Unclear risk	Unclear from text
Incomplete outcome data (attrition bias) All outcomes ‐ ITT analysis?	Unclear risk	Unclear from text
Selective reporting (reporting bias)	Low risk	VAS, Oswestry and Million’s Disability Indices (outcome measurements/results)
Similarity of baseline characteristics?	Low risk	Table 1
Co‐interventions avoided or similar?	Unclear risk	Unclear from text
Compliance acceptable?	High risk	Results paragraph two, Figure 2
Timing outcome assessments similar?	Low risk	Six, 12 months