Author's response to reviews Title: Treatment of Myofascial Trigger Points in Patients with Chronic Shoulder Pain: A Randomized Controlled Trial Authors:

The overall treatment strategy should be explained in the abstract. The treatment strategy is explained. Otherwise the potential reader could assume that only ischemic therapy was performed. The treatment strategy should also be reflected upon in the conclusion section of the abstract. Done Background: A clear hypothesis should be stated in the background section. The introductory lines have been rewritten to explain the hypothesis more accurately (within the limits of the word counts). Methods: The authors mention that a "set of self-administered questionnaire were used in the evaluation of the participants". However these outcomes are not defined clearly neither their use nor purposes in the current study. Were these questionnaires the ones used to create table 1. Please specify. “ A detailed medical history was taken, that included demographic variables and potential prognostic factors, and a set of self-administered questionnaires for outcome measurement”. Methods: the randomization section is clear to me. However there is no clear mention of the concealment strategy described in the manuscript. The strategy implemented to conceal the sequence until interventions is assigned needs to be described. Done. Methods: The precise nature of the prescribe exercises and ergonomic advice needs to be detailed in order to be clinically relevant for the clinician and research communities. Illustration may be helpful if permitted by the journal. This section has been expanded and three photographs have been added. Methods and results: the authors do not properly address the issue of possible co-interventions. Were they controlled, avoided, taken into account? The authors need to expand on this important issue. Information about co-interventions is added in the text. The allowed and uncontrolled self-management strategy poses some risks. The authors should clearly justify their choice and its possible impact on the study results and the overall generalization of their data. A comment is added to the limitations of the study section. Methods: the intention-to-treat strategy (preferred method) should be stated and clearly described. The intention to treat strategy is mentioned in the text. Discussion: Overall the discussion is well written and comprehensive. I would suggest the author discuss the following points. -The possible impact of having an underpowered study. This is mentioned in the text. -Is there a possible bias associated with the high rate of observers' capability to identify the group? An extra sentence is added to the text. Minor Essential Revisions -Background: A reference is needed for the last sentence of the second paragraph (definition of myofascial trigger points). Done. -Background: There is a syntax error in the last sentence of the third paragraph (Although....but the clinical). Done -Background: There is also a syntax error in the first sentence of the fourth paragraph. ...and may be combined refers to the MTrPs at the beginning of the sentence. The authors should make two sentences out of it. Done -Background: Even though the study by Hains is a small scale clinically based study, the author should reference the study in the introduction so the reader gets a full perspective of what was previously published on that topic. The Hains study is now mentioned in the introduction and in the discussion section as well. -The objective should be rewritten to simplify the sentence. The author might consider two sentences again. Which is done. -Methods: what is the "physical therapy practice for Neck, Shoulder, and Upper Extremity Disorders, Groningen, The Netherlands". Is this the full name of a clinic or the name and the location? Please specify. The use of capital letter seems to be arbitrary in the name. Done -Methods: Since direct access to physical therapy became available in the Netherlands in November 2006. Not relevant to the study. We have deleted this sentence. -Methods: The total number of palpated muscle should be stated in the data assessment section. A table of the palpated muscles is added. -Methods: The PDF transformation seems to have altered the text and mathematical symbols related to the stats, please verify. Done. In this section, it is not clear which variables were normally distributed and which were not and this should be clarified. The statistical analyses for VAS-P, ROM and number of muscle are not clearly described. This lack of description creates confusion in the results section. The author should specify what statistical analyses were performed for each of the variable and organize the results section so the read can identify the results associated with each of the analysis. We have made important corrections according to your recommendations. Statistical methods are better explained and results section and statistical section are revisited. -I am wondering if the number of muscle variable is normally distributed (probably not). Clarifications are needed. The number of muscles with active and latent MTrPs was in either group at intake, after 6 weeks and after 12 weeks normally distributed. I have double-checked it visually (comparing means and median) as well as with the Kolmogorov Smirnoff test. Even when we analyzed non-parametrically (Mann Whitney U statistic) the results were largely the same (no statistical difference at baseline and after 6 weeks, and statistically significant at 12 weeks (p=0.02). Therefore we chose to present means, difference of means, and t-test results. -Results: The author should clearly state if the group were comparable for each of the baseline characteristics. Done -Results: As stated in the introductory comment it looks like a ANCOVA was performed but the author talk about multiple linear regression while comparing results between groups. This is very confusing and clarifications are needed regarding the ANOVA model used, the ANCOVA (with covariables defined). Sentences like "Adding covariates did not change this result" are very confusing. This section is rewritten. -Again, correlation analyses, not described in the methods section are presented in the results section. Done -Discussion: relative risks (RR) should be defined and abbreviated the first time. Discretionary Revisions. Done -Methods Randomization section: After collection of all patient's data...Done -Methods: I would change the "intervention/control variable" to the "group variable" Done -Discussion: I don't believe the expression "were higher educated" is appropriate. I would suggest the participants had a higher level of education. Done Quality of written English: Needs some language corrections before being published. A native (American) speaker has checked the text thoroughly and has made a number of corrections. Statistical review: Yes, and I have assessed the statistics in my report. Declaration of competing interests: I declare that I have no competing interests