Reviewer's report 
 Persistent Demographic Differences in Colorectal Cancer Screening Utilization despite Title: 
Medicare Reimbursement 
 1  21 January 2005 Version: Date: 
 Gregory Cooper Reviewer: 
Reviewer's report: 
General 
A well written paper and well done analysis that provides more recent data on colon procedure use 
than in previous studies. 
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Major Compulsory Revisions (that the author must respond to before a decision on publication can be reached) 
1. A limitation in sample selection was exclusion of a potentially large number of managed care 
enrollees, as HMO penetration in Washington is probably higher than average. Although these patients should be excluded, the number of individuals who were excluded for this and other 
indications should be cited. 
2. Another limitation of this study is the relatively small number of minorities. This becomes relevant, 
for example, in some of the multivariable analyses where the confidence intervals appear large. This 
should be acknowledged as a limitation. 
3. Given the large sample size, a smaller p value should be used as a cut off in the univariate 
analyses to determine statistical significance. 4. The cross-sectional nature of the study is also a limitation as patients who may have previously undergone screening with a procedure recommended less frequently than yearly would have been 
classified as unscreened. 
5. Potential reasons for the highest screening rates in patients aged 70-74 and urban residents should be included in the Discussion. 
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Minor Essential Revisions (such as missing labels on figures, or the wrong use of a term, which the author can be trusted to correct) 
1. Abstract: Terms such as â €œinvasiveâ € and â €œscreeningâ € are used but not explained. 
2. Abstract: Data to support the first sentence of conclusions is not cited previously. 3. The term â €œscreeningâ € throughout the paper refers to both the procedural indication 
determined by diagnostic and procedure codes as well as procedure use in general. As this 
generates some confusion, would suggest using â €œscreening indicationâ € to refer to the former. 
4. Last sentence of â €œPatient Selectionâ € sentence of Methods is contradictory. 
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Discretionary Revisions (which the author can choose to ignore) 
None. 
 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 
 Persistent Demographic Differences in Colorectal Cancer Screening Utilization despite Title: 
Medicare Reimbursement 
 1  21 January 2005 Version: Date: 
 Gregory Cooper Reviewer: 
Reviewer's report: 
General 
A well written paper and well done analysis that provides more recent data on colon procedure use 
than in previous studies. 
------------------------------------------------------------------------------- 
Major Compulsory Revisions (that the author must respond to before a decision on publication can be reached) 
1. A limitation in sample selection was exclusion of a potentially large number of managed care 
enrollees, as HMO penetration in Washington is probably higher than average. Although these patients should be excluded, the number of individuals who were excluded for this and other 
indications should be cited. 
2. Another limitation of this study is the relatively small number of minorities. This becomes relevant, 
for example, in some of the multivariable analyses where the confidence intervals appear large. This 
should be acknowledged as a limitation. 
3. Given the large sample size, a smaller p value should be used as a cut off in the univariate 
analyses to determine statistical significance. 4. The cross-sectional nature of the study is also a limitation as patients who may have previously undergone screening with a procedure recommended less frequently than yearly would have been 
classified as unscreened. 
5. Potential reasons for the highest screening rates in patients aged 70-74 and urban residents should be included 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) 
1. Abstract: Terms such as â €œinvasiveâ € and â €œscreeningâ € are used but not explained. 
2. Abstract: Data to support the first sentence of conclusions is not cited previously. 3. The term â €œscreeningâ € throughout the paper refers to both the procedural indication 
determined by diagnostic and procedure codes as well as procedure use in general. As this 
generates some confusion, would suggest using â €œscreening indicationâ € to refer to the former. 
4. Last sentence of â €œPatient Selectionâ € sentence of Methods is contradictory. 
------------------------------------------------------------------------------- 
Discretionary Revisions (which the author can choose to ignore) 
None. 
 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 
 Persistent Demographic Differences in Colorectal Cancer Screening Utilization despite Title: 
Medicare Reimbursement 
 1  21 January 2005 Version: Date: 
 Gregory Cooper Reviewer: 
Reviewer's report: 
General 
A well written paper and well done analysis that provides more recent data on colon procedure use 
than in previous studies. 
------------------------------------------------------------------------------- 
Major Compulsory Revisions (that the author must respond to before a decision on publication can be reached) 
1. A limitation in sample selection was exclusion of a potentially large number of managed care 
enrollees, as HMO penetration in Washington is probably higher than average. Although these patients should be excluded, the number of individuals who were excluded for this and other 
indications should be cited. 
2. Another limitation of this study is the relatively small number of minorities. This becomes relevant, 
for example, in some of the multivariable analyses where the confidence intervals appear large. This 
should be acknowledged as a limitation. 
3. Given the large sample size, a smaller p value should be used as a cut off in the univariate 
analyses to determine statistical significance. 4. The cross-sectional nature of the study is also a limitation as patients who may have previously undergone screening with a procedure recommended less frequently than yearly would have been 
classified as unscreened. 
5. Potential reasons for the highest screening rates in patients aged 70-74 and urban residents should be included 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) 
1. Abstract: Terms such as â €œinvasiveâ € and â €œscreeningâ € are used but not explained. 
2. Abstract: Data to support the first sentence of conclusions is not cited previously. 3. The term â €œscreeningâ € throughout the paper refers to both the procedural indication 
determined by diagnostic and procedure codes as well as procedure use in general. As this 
generates some confusion, would suggest using â €œscreening indicationâ € to refer to the former. 
4. Last sentence of â €œPatient Selectionâ € sentence of Methods is contradictory. 
------------------------------------------------------------------------------- 
Discretionary Revisions (which the author can choose to ignore) 
None. 
 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