PONE-D-19-23082

Describing the indescribable: A qualitative study of dissociative experiences in psychosis

PLOS ONE

Dear Dr Černis,

Thank you for submitting your manuscript to PLOS ONE. Three reviewers have read and commented on your manuscript. All of them highlighted its merit. Several problems have been highlighted not only once, and after my own reading, I agree with the reviewers' judgements. In particular, the methodology is not yet sufficiently described. It would be very important that the content analysis is described in such a way to allow others to do the same you did. At this point, I would also like to highlight that only one person coded the data, which is problematic. It does not allow the assessment of an inter-rater reliability.

Please also note that your data would need to be made accessible. 

In sum, we feel that your manuscript has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

We would appreciate receiving your revised manuscript by Nov 14 2019 11:59PM. When you are ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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We look forward to receiving your revised manuscript.

Kind regards,

Christine Mohr, PhD

Academic Editor

PLOS ONE

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1. You indicated that you had ethical approval for your study. In your Methods section, please ensure you have also stated whether you obtained consent from parents or guardians of the minors included in the study or whether the research ethics committee or IRB specifically waived the need for their consent.

2. Please describe in your methods section how capacity to consent was determined for the participants in this study.

3.

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Partly

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: N/A

Reviewer #2: Yes

Reviewer #3: N/A

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: No

Reviewer #2: No

Reviewer #3: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: In this study the authors conducted interviews with 12 people with non-affective psychosis diagnoses regarding their experiences of dissociation. Thematic analysis was used to analyse the interview transcripts. The results cover the phenomenology of dissociation, factors that modulate dissociative experiences, and the impact of these experiences in this population.

I thoroughly enjoyed reading the manuscript, which is engaging and very well written. A qualitative approach was well suited to the aims of the study. The results are of importance for clinicians who work with people experiencing psychosis and for researchers seeking to understand dissociative experiences in psychosis, how they interact in psychotic experiences, and treatments that might ameliorate their impact. This is important because definitions of dissociation are wide ranging and it can be under-recognised in clinical practice. One weakness of the study is the lack of credibility checks of the qualitative analysis – there was only one rater and it is not clear whether team discussions were held regarding the themes or any process of checking within the team. There was also not a process of respondent checks of the themes. However, the authors do recognise this, and there are other strengths, such as lived experience input to the interview development. I believe the novelty and applicability of the results still make this an important contribution to the literature.

I just have a few very minor comments that the authors might address in order to improve the manuscript.

1. The authors list participant’s diagnoses, but is it not clear how these were ascertained – was this self-report, or based on case notes?

2. In the flow chart showing recruitment of the final sample 2 people are listed as excluded with the reason “would struggle to participate in a focused interview”. This was not in the exclusion criteria, therefore may need more explanation. Is potentially important because it means that certain people’s voices are not heard, and this was a decision made (presumably) by the researchers. Understanding this decision-making process may help to situate who the sample does (and does not) include as a result of this decision.

3. I think it would be useful to see the interview guide as supplementary material

4. It would be helpful to have some indication of the length of the interviews (average and range)

5. Given that only one researcher conducted the analysis, it might help to include a brief ‘reflexive statement’ regarding the researcher world view etc. and acknowledge how this might have influenced the construction of meanings in the analysis (e.g. does the researcher work predominantly within a CBT model? (which might have influenced constructions of meaning).

6. Line 205: I had to look up what ‘haptic perception’ was! Perhaps including a definition might be useful.

Reviewer #2: This is a very important qualitative investigation of the experience of dissociation in a group of 12 people with non-affective psychosis. I have the following comments for the authors:

It would be helpful to include data on percentages of people with dissociative disorders or symptoms in groups with psychosis rather than just “elevated” to give the reader a sense of the context of the problem.

The idea that there is a complex relationship between dissociative and psychotic symptoms is referred to throughout the whole paper. I think you need to be clearer about this and to outline, as you see it, the possible ways that dissociative and psychotic symptoms may interact. You seem to be saying that they may be different constructs that are sometimes misdiagnosed (in either direction) or that they are not necessarily different constructs (of course, there are then myriad ways in which they could be ‘overlapping”). I understand that you don’t really want to get deeply into the complexities of this in your article but the reality is you are making conclusions about it, suggesting that you do need to be clearer about all the potential ways there could be a relationship.

e.g. “Some readers may argue that it is difficult – or impossible – to make distinctions between psychotic and dissociative symptoms since they overlap, and because many apparently psychotic symptoms may in fact be dissociative (and vice versa).” This sentence suggests that you need to have covered this argument in your introduction.

A lot more detail about the method is needed. In particular the development of the topic guide and the thematic analysis method used. For example - how did the team work together to ensure the robustness of the analysis? How was the negative case analysis undertaken? More information on the process of developing the topic guide with the advisory group is needed. What lived experience did the advisory group have? How negative case analysis was undertaken should be described.

The analysis sections should be referenced more thoroughly.

It is somewhat unusual to deductively analyse by research question in a thematic analysis. In doing this then you must give a rationale for why the particular research questions chosen are central to your overall aim of furthering understanding of dissociation in those with psychosis. Why these particular four research questions should be outlined in the introduction.

More detail and rationale of the sample selection is needed:

The authors have described in detail how a decision was made regarding whether a participant met the inclusion criteria of having dissociation after having been referred to the study. An equally detailed description should be given of how participants were referred to the study. From the flow chart it seems that only three participants did not have dissociative experiences that met criteria for the study, suggesting that a lot of selection was done by non-researchers in the lead up to recruitment. This is not a criticism of the study it just needs to be clearly described as it impacts the make-up of the sample.

Three participants had symptoms on the DES under 10 and within the normal range while the rest of the sample scored over 30 (clinically significant). If a DES cut-off was to be used, why was it at the average in the normal population and not at a higher clinical cut-off? Did those participants with DES scores in the normal range appear in any way different than those in the clinical range? The bi-modal distribution within the sample needs to be discussed.

It would be helpful to describe the Garety model in more detail either in the introduction or discussion. Many readers may not be familiar with it.

The central idea derived from the thematic analysis of ‘a felt sense of anomaly” is interesting and important. I have some comments on the way you have discussed this theme: it important to be clear this this is how you have constructed dissociation to be felt/sensed etc in those with psychosis, not more generally. This is important because “anomaly’ is so central to symptom constructs in psychosis (i.e. Garety model). It’s also important to remember that some of your group (the 3 with low DES scores) may not have met any kind formal criteria for dissociative symptoms- how can we be sure that this sense of anomaly is not about psychotic symptoms?

Reviewer #3: It is an interesting and important paper but it needs revion an d more elaboration.

The method need to be more and better explaind. Which method. how- acoording to whom needs to be there.

Teh resluts section needs to be more elabortaded -the htemes should be clearly shown - preferably in a figure as suggested by Braum and Clarke which is method according to who´s method I think the authors have used.

The themes more elaborated and analysed- for example feeling unreal- a theme which is connected with disconnetedness and a theme that aslo seem to be long to when dissociation starts and when it can stop. So more working with the themes. Then I think this paper can be vey good.

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Reviewer #1: No

Reviewer #2: No

Reviewer #3: Yes: Doris Nilsson

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files to be viewed.]

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PONE-D-19-23082R1

Describing the indescribable: A qualitative study of dissociative experiences in psychosis

PLOS ONE

Dear Dr Černis,

as you will see, the three original referees agreed to again review your revision of this manuscript. All of them were pleased with the efforts and care you have taken. While one referee is happy to accept the manuscript as is, the other two referees asked for some minor attention to the manuscript (specify the use of the DES, have a final careful read of the manuscript)

Accordingly, I am happy to communicate that your manuscript has been judged scientifically suitable for publication. At this point, I cannot  formally accept this manuscript for publication, but can informally confirm that it will be accepted once the final changes have been performed and submitted. 

Please add these very minor changes as quickly as possible to the manuscript. I am than happy to accept the manuscript. 

When you are ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A marked-up copy of your manuscript that highlights changes made to the original version. This file should be uploaded as separate file and labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. This file should be uploaded as separate file and labeled 'Manuscript'.

I am looking forward to receiving your revised manuscript.

Kind regards,

Christine Mohr, PhD

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: (No Response)

Reviewer #3: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: (No Response)

Reviewer #2: Yes

Reviewer #3: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: (No Response)

Reviewer #2: N/A

Reviewer #3: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: (No Response)

Reviewer #2: No

Reviewer #3: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: (No Response)

Reviewer #2: Yes

Reviewer #3: Yes

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: (No Response)

Reviewer #2: Congratulations to the authors for such thorough attention to reviewers’ comments.

I only have only one small question now in response to changes made. This line in the method implies that the DES questions were asked in relation to symptoms the past 2 weeks: “the DES score reflects that the participants had not experienced dissociation within the past two weeks, not that they had never experienced higher levels.” My understanding of the DES was that it does not require scale items to be present with last 2 weeks so I’m unclear how the DES was used in the current study. Could this be clarified please?

Reviewer #3: The authors have done a good job adressing reviewer comments. I also now think that this piece of research on dissociation has possiblity to put research forward.

Just check all the sentences once more so that there will be no mistakes.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Rachel M Brand

Reviewer #2: No

Reviewer #3: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files to be viewed.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email us at figures@plos.org. Please note that Supporting Information files do not need this step.

Describing the indescribable: A qualitative study of dissociative experiences in psychosis

PONE-D-19-23082R2

Dear Dr. Černis,

Thank you for making the last minor changes to your manuscript. We are now pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it complies with all outstanding technical requirements.

Within one week, you will receive an e-mail containing information on the amendments required prior to publication. When all required modifications have been addressed, you will receive a formal acceptance letter and your manuscript will proceed to our production department and be scheduled for publication.

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With kind regards,

Christine Mohr, PhD

Academic Editor

PLOS ONE

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