Reviewer's report 
 The Impact of Illness in Patients with Moderate to Severe Gastro Esophageal Reflux Disease Title: 
 1  15 April 2005 Version: Date: 
 Stefan N Willich Reviewer: 
Reviewer's report: 
General 
The article by El-Dika and coworkers deals with the impact of GERD on health realted quality of life 
(HRQOL) and work productivity, an important topic both from a public health from a methods perspective. 
------------------------------------------------------------------------------- 
Major Compulsory Revisions (that the author must respond to before a decision on publication can 
be reached) 
The work aims to investigate the im Pact of GERD on HRQOL. According to the introduction (p.6), 
the validity of utility instruments as HRQOL measures is another aim. And according to the methods 
section “the primary aim of the study is the comparison of two different formats of administering” the 
standard gamble and the feeling thermometer. The authors could be more precise on the aim (or the 
primary and secondary aims) of their study. 
The impact of GERD on HRQOL and work productivity has been analysed in detail and with larger 
patient samples elsewhere. The interesting new aspect of this study is the use of utility instruments 
as measures of HRQOL in patients with GERD. The authors should put the focus of their paper 
more clearly on this part of their study. 
Subscales of SF-36 baseline are presented (table 6), but are not put in any context, e.g. correlated 
with the utility instruments or compared to other diseases, studies etc (besides: some N are 
missing). The authors compare the SF-36 component scales to data elsewhere published (table 7). 
Are these populations comparable in terms of gender, age, concomittant diseases etc? This should 
be mentioned in the discussion. 
------------------------------------------------------------------------------- 
Minor Essential Revisions (such as missing labels on figures, or the wrong use of a term, which the author can be trusted to correct) 
Minor revisions include some missing data/informations: the correlations between the utility 
instruments and other questionnaires (QOLRAD, SF-36, Symptoms) are shown, but the change scores for the utility instruments are missing. Of course, the responsiveness to change of an 
HRQOL instrument is an important information. If possible, it should be added. Symptoms are 
assessed by the “four symptoms questionnaire”. Please explain if this is a previously validated instrument. 
------------------------------------------------------------------------------- 
Discretionary Revisions (which the author can choose to ignore) 
 Unable to decide on acceptance or rejection until the authors have responded to the What next?: 
major compulsory revisions 
 An article of importance in its field Level of interest: 
 Acceptable Quality of written English: 
 No Statistical review: 
Declaration of competing interests: 
I declare that I have no competing interests 
Reviewer's report 
 The Impact of Illness in Patients with Moderate to Severe Gastro Esophageal Reflux Disease Title: 
 1  15 April 2005 Version: Date: 
 Stefan N Willich Reviewer: 
Reviewer's report: 
General 
The article by El-Dika and coworkers deals with the impact of GERD on health realted quality of life 
(HRQOL) and work productivity, an important topic both from a public health from a methods perspective. 
------------------------------------------------------------------------------- 
Major Compulsory Revisions (that the author must respond to before a decision on publication can 
be reached) 
The work aims to investigate the im Pact of GERD on HRQOL. According to the introduction (p.6), 
the validity of utility instruments as HRQOL measures is another aim. And according to the methods 
section “the primary aim of the study is the comparison of two different formats of administering” the 
standard gamble and the feeling thermometer. The authors could be more precise on the aim (or the 
primary and secondary aims) of their study. 
The impact of GERD on HRQOL and work productivity has been analysed in detail and with larger 
patient samples elsewhere. The interesting new aspect of this study is the use of utility instruments 
as measures of HRQOL in patients with GERD. The authors should put the focus of their paper 
more clearly on this part of their study. 
Subscales of SF-36 baseline are presented (table 6), but are not put in any context, e.g. correlated 
with the utility instruments or compared to other diseases, studies etc (besides: some N are 
missing). The authors compare the SF-36 component scales to data elsewhere published (table 7). 
Are these populations comparable in terms of gender, age, concomittant diseases etc? This should 
be mentioned in the discussion. 
------------------------------------------------------------------------------- 
Minor Essential Revisions (such as missing labels on figures, or the wrong use of a term, which the author can be trusted to correct) 
Minor revisions include some missing data/informations: the correlations between the utility 
instruments and other questionnaires (QOLRAD, SF-36, Symptoms) are shown, but the change scores for the utility instruments are missing. Of course, the responsiveness to change of an 
HRQOL instrument is an important information. If possible, it should be added. Symptoms are 
assessed by the “four symptoms questionnaire”. Please explain if this is a previously validated instrument. 
------------------------------------------------------------------------------- 
Discretionary Revisions (which the author can choose to ignore) 
 Unable to decide on acceptance or rejection until the authors have responded to the What next?: 
major compulsory revisions 
 An article of importance in its field Level of interest: 
 Acceptable Quality of written English: 
 No Statistical review: 
Declaration of competing interests: 
I declare that I have no competing interests 
Please review this paper.
user
Reviewer's report 
 The Impact of Illness in Patients with Moderate to Severe Gastro Esophageal Reflux Disease Title: 
 1  15 April 2005 Version: Date: 
 Stefan N Willich Reviewer: 
Reviewer's report: 
General 
The article by El-Dika and coworkers deals with the impact of GERD on health realted quality of life 
(HRQOL) and work productivity, an important topic both from a public health from a methods perspective. 
------------------------------------------------------------------------------- 
Major Compulsory Revisions (that the author must respond to before a decision on publication can 
be reached) 
The work aims to investigate the im Pact of GERD on HRQOL. According to the introduction (p.6), 
the validity of utility instruments as HRQOL measures is another aim. And according to the methods 
section “the primary aim of the study is the comparison of two different formats of administering” the 
standard gamble and the feeling thermometer. The authors could be more precise on the aim (or the 
primary and secondary aims) of their study. 
The impact of GERD on HRQOL and work productivity has been analysed in detail and with larger 
patient samples elsewhere. The interesting new aspect of this study is the use of utility instruments 
as measures of HRQOL in patients with GERD. The authors should put the focus of their paper 
more clearly on this part of their study. 
Subscales of SF-36 baseline are presented (table 6), but are not put in any context, e.g. correlated 
with the utility instruments or compared to other diseases, studies etc (besides: some N are 
missing). The authors compare the SF-36 component scales to data elsewhere published (table 7). 
Are these populations comparable in terms of gender, age, concomittant diseases etc? This should 
be mentioned in the discussion. 
------------------------------------------------------------------------------- 
Minor Essential Revisions (such as missing labels on figures, or the wrong use of a term, which the author can be trusted to correct) 
Minor revisions include some missing data/informations: the correlations between the utility 
instruments and other questionnaires (QOLRAD, SF-36, Symptoms) are shown, but the change scores for the utility instruments are missing. Of course, the responsiveness to change of an 
HRQOL instrument is an important information. If possible, it should be added. Symptoms are 
assessed by the “four symptoms questionnaire”. Please explain if this is a previously validated instrument. 
------------------------------------------------------------------------------- 
Discretionary Revisions (which the author can choose to ignore) 
 Unable to decide on acceptance or rejection until the authors have responded to the What next?: 
major compulsory revisions 
 An article of importance in its field Level of interest: 
 Acceptable Quality of written English: 
 No Statistical review: 
Declaration of competing interests: 
I declare that I have no competing interests 
assistant