3. Cochrane Back Review Group Quality Items.

Quality items	Scoring of item	Notes about scoring
A. Was the method of randomization adequate? Yes/No/Don't know	A random (unpredictable) assignment sequence. Examples of adequate methods are computer generated random number table and use of sealed opaque envelopes. Methods of allocation using date of birth, date of admission, hospital numbers, or alternation should not be regarded as appropriate.
B. Was the treatment allocation concealed? Yes/No/Don't know	Assignment generated by an independent person not responsible for determining the eligibility of the patients. This person has no information about the persons included in the trial and has no influence on the assignment sequence or on the decision about eligibility of the patient.
C. Were the groups similar at baseline regarding the most important prognostic indicators? Yes/No/Don't know	In order to receive a "yes," groups have to be similar at baseline regarding demographic factors, duration and severity of complaints, percentage of patients with neurologic symptoms, and value of main outcome measure(s).
D. Was the patient blinded to the intervention? Yes/No/Don't know	The reviewer determines if enough information about the blinding is given in order to score a "yes."	We scored sham controlled trials as .5 (rather than 1) for patient blinding because even though these trials used a sham control, we cannot be certain that the sham was sufficiently credible to allow patients to be blinded to the true treatment being evaluated. The only exception was trials that evaluated the credibility of the sham, and found the sham to be indistinguishable from the acupuncture.
E. Was the care provider blinded to the intervention? Yes/No/Don't know	The reviewer determines if enough information about the blinding is given in order to score a "yes."
F. Was the outcome assessor blinded to the intervention? Yes/No/Don't know	The reviewer determines if enough information about the blinding is given in order to score a "yes."	For determining whether the outcomes assessor was blinded, we always considered the patient to be the outcomes assessor for patient rated outcomes (ie, WOMAC), even if the outcomes data was collected by someone else. We scored sham controlled trials as .5 (rather than 1) for outcomes assessor blinding because even though these trials used a sham control, we cannot be certain that the sham was sufficiently credible to allow patients to be blinded to the true treatment being evaluated. The only exception was trials that evaluated the credibility of the sham, and found the sham to be indistinguishable from the acupuncture.
G. Were co‐interventions avoided or similar? Yes/No/Don't know	Co‐interventions should either be avoided in the trial design or similar between the index and control groups.
H. Was the compliance acceptable in all groups? Yes/No/Don't know	The reviewer determines if the compliance to the interventions is acceptable, based on the reported intensity, duration, number and frequency of sessions for both the index intervention and control intervention(s).
I. Was the drop‐out rate described and acceptable? Yes/No/Don't know	The number of participants who were included in the study but did not complete the observation period or were not included in the analysis must be described and reasons given. If the percentage of withdrawals and drop‐outs does not exceed 20% for short‐term follow‐up and 30% for long‐term follow‐up and does not lead to substantial bias a "yes" is scored. (N.B. these percentages are arbitrary, not supported by literature).
J. Was the timing of the outcome assessment in all groups similar? Yes/No/Don't know	Timing of outcome assessment should be identical for all intervention groups and for all important outcome assessments.
K. Did the analysis include an intention‐to‐treat analysis? Yes/No/Don't know	All randomized patients are reported/analyzed in the group they were allocated to by randomization for the most important moments of effect measurement (minus missing values) irrespective of noncompliance and co‐interventions.

Note: There is a maximum total of 11 points on the Cochrane Back Review Group scale, with each item scored as 1 for 'Yes', and 0 for 'No' or 'Don't know' (except where indicated in 'Notes about scoring' column). Lower quality = 0‐6; higher quality = 7‐11.