Title: Cognitive flexibility in verbal and nonverbal domains and decision making in anorexia nervosa patients: a pilot study.

Transcription

1 Author's response to reviews Title: Cognitive flexibility in verbal and nonverbal domains and decision making in anorexia nervosa patients: a pilot study. Authors: Giovanni Abbate-Daga (giovanni.abbatedaga@unito.it) Sara Buzzichelli (sara.buzzichelli@gmail.com) Federico Amianto (federico.amianto@unito.it) Giuseppe Rocca (giuseppe.rocca@unito.it) Enrica Marzola (enrica.marzola@gmail.com) Shawn M McClintock (Shawn.McClintock@utsouthwestern.edu) Secondo Fassino (secondo.fassino@unito.it) Version: 3 Date: 24 August 2011 Author's response to reviews: see over

2 Dear Sabina Alam, We are now submitting a second revision of our paper. As suggested by AE Dr. L.Lilenfeld, our manuscript has been thoroughly edited by a native English speaker; we also corrected the typos of the previous version. Please let us know any further needed change. Best regards, 24 th August 2011 Dr Giovanni Abbate-Daga

3 Reviewer #1 Francesca Brambilla: We would like to thank the reviewer for her useful comments. 1. Background, 4th paragraph, line 4 from the top. It is inappropriate to say "AN patients, not affected by any frontal damage" since it has been repeatedly reported that frontal damages do exists and have been reported in many patients in the long lasting disorder. Since the test is not administered after running appropriate brain imaging researches, I would omit this sentence or explain it better. We eliminated this sentence. 2. Background, 5th paragraph, line 5 from the top. The authors should introduce also a correlation with disease duration, because this datum may have a relation with severity of the disease, since longer is the disorder more severe are the damages done by the disease itself on brain functioning. It should be possible to do it since the authors report disease duration in table 1. We added disease duration. We described the statistical analysis in the method section explaining that we performed a linear correlation between years of illness and neuropsychological tests. The results of the correlations are shown in the clinical and demographic features of the sample section of the results. We explained this issue in the second paragraph of the discussion. 3. Methods, first paragraph. It is not mentioned if there was a different severity of the disease between the 3 groups of patients. This is important since a different severity could influence the responses to the test. We assessed differences in severity of illness between inpatients and outpatients and differences in neuropsychological tests performances with a t-test. Results of the t-test are shown in the Clinical and demographic features of the sample section. In the discussion, we explained the data in the third paragraph. 4. It should be important to introduce a correlation not only with depression but also with anxiety which might strongly influence the flexibility. Since I believe that the

4 authors did not administer rating scales specific for anxiety, since they would have mentioned it in the text, and since obviously is not possible to do it now, I would suggest to mention it at least as a limitation of the study and propose it as necessary for future researches. We added a paragraph as follows: Moreover, in the present study we didn t evaluate the anxious symptomatology that could modify the neurocognitive performances. Even if previous papers didn t show effects of anxious symptomatology on set shifting in AN patients future research on cognitive flexibility of eating disorders is warranted to clarify this issue.

5 Reviewer #2 Janet Treasure: Thank you for your kind comments. 1. A weakness of this study is that the authors did not measure IQ as a confounder. Discussion, fifth paragraph: On the other hand it is well-known that the IQ of these patients is higher than average and it is not lowered by their low weight: these data seem to suggest that less years of education of these patients can be due to the illness and not to impaired intellective abilities. 2. Also there can be problems with controlling for BMI as this is so entwined with the illness. Both sets of data are given with or without this confounding. It would be useful to have this limitation noted in the discussion. Discussion, sixth paragraph: Theoretically, the correlation between BMI and some performances at WCST is difficult to explain in a cross-sectional study. The low BMI is indeed so entwined with the disease to make it impossible to distinguish if it can impair the test performance or if it represents an illness severity index of patients with premorbid deficits in cognitive flexibility. In some studies recovered patients were found to have a poor set shifting. Moreover, a recent study on 215 AN patients found that the BMI is not related to the performances at the Brixton test. Therefore future researches are needed to widely investigate the issue of the neuropsychological effects of malnutrition because it is probable that BMI influenced by several factors - per se is too inaccurate as an index. These factors should be deepened both separately and then with only one index the BMI reassuming them all. 3. Table 2. In the legend the meaning of the answer type U, S etc should be made clear. We added a legend for Answer C, U and S; we hope Table 2 is clearer now.