Line also line 90: It is very hard to understand what the authors mean.these sentences needs re-writing.

Transcription

1 Reviewer s report Title: Changes in event-related potentials in patients with first-episode schizophrenia and their siblings Version: 0 Date: 07 Jun 2016 Reviewer: Farzaneh Saeedzadeh Sardahaee Reviewer's report: This article tries to address an interesting research question. The Authors need to provide more background information as to why the research question is important.the language used in this article can be much improved, see below for specific examples. The tables as well as the text is written hastily and needs further work. Tables lack footnotes With specification such as confidence intervals, what P or F stand for, or units for measurements(are they in miliseconds, or?), further specification in the footnote as which p-values were deemed significant. Line 70: In the background section, authors write about social cognition. It would be helpful if they could specify what they mean by "social cognition". Line 83: Authors also claim that unaffected sibling og patients diagnosed with schizophrenia have an increased familial risk for schizophrenia. They do not, however, provide any Reference here. Line also line 90: It is very hard to understand what the authors mean.these sentences needs re-writing. Line 108: Do Authors mean "P100" by "P1"?

2 Line 108: Do Authors mean that "prescence" of an impaired P100 component is established in patinets With Schizophrenia? The way this sentence is written can be interpretted as impairment in P100 component is an established fact amongs patients With schizophrenia. line 115: Authors refer to an unpublished study by the same Group studying facial recognition deficits in patients With schizophrenia and healthy Controls. They og further on to say that their findings yielded "Limited" information for high-risk unaffected population. The study has in fact yielded "no" information about high risk unaffected population. Under Method section: Selection process of patient population can be further described in a figure. How many first episode schizophrenia cases were admitted to EASY, Shanghai Mental Health Center between May 2008 and May 2011? Authors refer to a previously published article(ref. number 9) were study population is described but in the refrence article, there is discrepency in the recruitment time. The Authors mention that the duration of illness was less than 3 years. Does this include prodromal phase? Line 128: Authors Write "first degree relatives".this is repeated in line 184 under result section. There is a clear differnce between first degree relatives and siblings. Line 164: What is the eye-movement correction algorithm used here? Authors need to provide a refrence here. Statistical analysis: Sup. table 1: what is confidence interval? it would be good if Authors prvide a footnote for the table.the same applies to sup. table 2.

3 Some of patinet Group were under treatment With antipsychotics- Aripiprazole, Olanzapine and Risperidone. There is a big difference in these Three Groups in doasage, expected antipschotic effects as well as side-effects. Whilst 10 mg daily dose of Aripiprazole is not a big dose, 4 mg Risperidone is quite bigger both in dosage and side effect. Have Authors reflected upon how this difference might affect their findings? Line : It is difficult to know what Authors mean by "within subjects". Are these patinets, unaffected siblings or Controls? Discussion: Line 217: What are "subtle facial emotion recognition impairments"? Line : Since Authors have patients on medication, they can not assume that the impairment in facial recognition is only due to schizophrenia. They do not specify whether their patient Group recieved any other medication With potential efefcts on facial recognition task performance,either. Line : What do Authors mean by "within a Distributed brain network" or "this brain network"?(also repeated in line 248) Line : What do Authors mean by "generalized form of cognitive impairment"?how do Authors conclude any structural deficit? They have not studied anatomical structural difference in their study. Line 245: Why is it assumed that facial Expression recognition is harder to detect amongst siblings? If the tests measure what they are supposed to, the defcet should be equally detectable amongst siblings given that enough many subjects are studied. Line : This statement goes against what authors claim to have been able to study.

4 Line : Reference is needed here. Are the methods appropriate and well described? If not, please specify what is required in your comments to the authors. No Does the work include the necessary controls? If not, please specify which controls are required in your comments to the authors. Yes Are the conclusions drawn adequately supported by the data shown? If not, please explain in your comments to the authors. No Are you able to assess any statistics in the manuscript or would you recommend an additional statistical review? If an additional statistical review is recommended, please specify what aspects require further assessment in your comments to the editors. I am able to assess the statistics Quality of written English Please indicate the quality of language in the manuscript: Not suitable for publication unless extensively edited Declaration of competing interests Please complete a declaration of competing interests, considering the following questions: 1. Have you in the past five years received reimbursements, fees, funding, or salary from an organisation that may in any way gain or lose financially from the publication of this manuscript, either now or in the future? 2. Do you hold any stocks or shares in an organisation that may in any way gain or lose financially from the publication of this manuscript, either now or in the future?

5 3. Do you hold or are you currently applying for any patents relating to the content of the manuscript? 4. Have you received reimbursements, fees, funding, or salary from an organization that holds or has applied for patents relating to the content of the manuscript? 5. Do you have any other financial competing interests? 6. Do you have any non-financial competing interests in relation to this paper? If you can answer no to all of the above, write 'I declare that I have no competing interests' below. If your reply is yes to any, please give details below. I declare that I have no competing interests. I agree to the open peer review policy of the journal. I understand that my name will be included on my report to the authors and, if the manuscript is accepted for publication, my named report including any attachments I upload will be posted on the website along with the authors' responses. I agree for my report to be made available under an Open Access Creative Commons CC-BY license ( I understand that any comments which I do not wish to be included in my named report can be included as confidential comments to the editors, which will not be published. I agree to the open peer review policy of the journal