Comparing Self-Administered Web-Based to Interviewer-Led 24-h Dietary Recall (FOODCONS): An Italian Pilot Case Study

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The article titled “Comparing Self-Administered Web-Based to Interviewer-Led 24-Hour Dietary Recall: An Italian Pilot Case Study” describes a necessary and valuable study, but it requires:

-       -     very careful and precise language proofreading, with precise verification of the clarity of sentences (e.g. “Thirty-nine adult volunteers the sample of was randomized in A and B groups: test method first vs reference method and vice versa” or “assessing the environmental impact of the diet”, “The 24h recall technique requires the use of dietician or well-trained personnel and a specially developed software to record the food consumed”) - the current language of the work is difficult to read

-         -    explanation of CATI, CAPI concepts

-        -    explaining whether the size of the group of 39 people can be sufficient to draw conclusions

-         -   consideration of the method for pairs of repeated results in statistical evaluation (test and reference method) (Wilcoxon signed-rank test for dependent pairs); were data distributions checked?

-        -    placing e.g. names of statistical tests under tables

-       -     requires a hypothesis to be written in the introduction and verified in the discussion

-        -    conducting a discussion based on the results of other publications (the discussion lacked references to research by other authors)

-       -     a solid discussion of the strengths and weaknesses of the study

Comments on the Quality of English Language

The paper requires very careful and precise language proofreading, with precise verification of the clarity of sentences - the current language of the work is difficult to read.

Author Response

please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

ABSTRACT

Present the results in abstract more clearly and correct the objective of the study (energy, nutrient and food group intake)

INTRODUCTION

Ln 73 - correct the 'e' to 'and'

Ln 77 – 80 - in addition to energy and nutrient intake, the comparison of the daily intake of food groups is also presented - it must be added to the objective of the study

MATERIALS AND METHODS

Ln 91 – separate reference with comma and not semicolon

Ln 102 – delete the point before reference

Ln 107 – add comma after brackets and before cholesterol

Ln 111 – Please better clarify whether folate is the sum of dietary folate and folic acid expressed in folate equivalent, or whether dietary folate intake in mcg, folic acid intake in mcg and folate intake as folate equivalent can be monitored separately

Subjects’ recruitment – State how many of participants were recruited and excluded from the analysis with explained reasons

Ln 131-136 – add reference for this methodology protocol

Ln 149 – indicate which descriptive statistics were presented. Also include the interquartile range with the median of variables, as readers will not receive complete information this way (especially as the data are not normally distributed – assumption on the test used for further analysis). Generally, for the descriptive statistics I suggest to carried on Shapiro-Willk test to examine the normality of the data and use the mean and SD or the median and interquartile range.

Another suggests for the statistical analysis is to use the Wilcoxon signed rank test (not-normal distribution) or pair-t-test (normal distribution) for the estimation of the differences between methods because the differences were tested on the same population.

Explain in more detail how did you plotted the Bland-Altman plots. The Bland-Altman plots are only for energy, macronutrients and alcohol – explain why; if you plotted BA for all nutrients you may added to the supplementary files

Ln 158 – 160 – clarify is it calculated for energy and nutrients or for the amount of the food groups

It is necessary to add a description of how the 24-hour recall was collected in the interview.

in view of the fact that 24h recalls were collected twice using two different recall methods, it should be emphasized that the mean value of the measurement is given on two occasions per participant.

Were socio-demographic and anthropometric data collected that could provide a better description of the sample and deepen the discussion?

RESULTS

Ln 169 – the p value for the linoleic acid is 0.061 which means it is also not statistically significant. Please check the value in the table 1

Ln 170 – delete the period between words methods and for; highlight in the title of the table that this is the differences between methods

Table 1 – explain which test did you used for p value in the notes below the table; enter the p-values for all variables as three-digit decimal numbers; change retinol eq to vitamin A (μg RE); The methodology states that several types of vitamins and minerals can be extracted from the software, but not all are listed in the table. Please explain why only certain vitamins and minerals have been selected for processing and display.

Figure 2 – Revise all the plots in the Figure 2; some of them are lacking with the name of axis; write on the lines if they present mean/median and 2SD/2.5^th and 97.5^th percentile and the values of it; missing the lines in alcohol plot; It is more common to title plots A, B, C etc. and to explain in the title what is contained in which plot.

Table 2 – the data on mean values are already presented in the table 1. I suggest to merge this two tables; Moreover, these variables (except mean ratio) are presented in the Figure 2, however, they are not highlighted on the plots; In addition, explain why did you choose only few of the nutrients to present – they differed from the table 1 and from the Figure 2; in the title of the table name two methods; add the number of the participants

The Spearman’s correlations between the self-administered and the interviewer-led recall for the same for nutrient intakes were not presented in the results, as it was written in the methodology.

Table 3. - The methodology does not describe the criteria or guidelines used to categorize foods into food groups. It also does not specify what statistical tests were carried out to test the differences or relationships between the methods for the food group; why did you present the differences in mean but not tested them; check the normality of data and use proper tests; present p Values of the correlation; add space between numbers and ±; in the title of the table name two methods; add the number of the participants

It would be interesting if BA plots for food groups were also shown (supplementary data).

Table 4 – state that the numbers are % of the participant as it is not clear from the table; rewrite the title of the table to make it easier to understand what is in the table; add total number of the participants

Table 5 – add total number of the participants; it seems that the analysis of the questionnaire evaluation was on 41 participants. Why you did not exclude two participants which were excluded in the other analysis?

DISCUSSION

The discussion is in generally well written however it lake of the comparison with the previous studies. In addition, it might be separated in four paragraphs (nutrient intake; food group intake; evaluation; limitations & strength) to make it easier to read

 

REFERENCE

Check the references – double numbers; some number are in italic; spaces between names; periods after authors names; missing data on volumes, pages numbers of article number

Author Response

please find the attachment 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Thank you for all the explanations and additions to the text. It is only incomprehensible why the results were not compared with the test for pairs repeated in the experiment using two methods - the authors did not explain this issue.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors,

You have answered all my concerns, you put a great effort in the reviewing process.

However, I noticed few more things for review

INTRODUCTION

Ln 48 – 51 Add appropriate reference

METHODS

Write how did you plot the BA plots in Statistical analysis subheading

RESULTS

Table 1 – delete letter “b” after vitamin A in the first column

DISCUSSION

Ln 298 – 300 Please write this sentence more clearly, because it is not clear the way it is written.

COCLUSIONS

Write conclusion as separate paragraph after the Conclusions heading

Author Response

Please see the attachment.

Author Response File: Author Response.pdf