Cass article, Discussion Forum

Review discussion of "End stage renal disease in Aborigines in New South Wales"

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Index

Review by Mark Thomas 21.4.99
Comment by William Wang 24.4.99
Response from author 27.4.99
Review by John Kelly 3.5.99
Response to John Kelly from author 4.5.99
Statistical Review by Michael Coory 14.5.99
Response to Michael Coory from author 15.5.99
Editors' decision - Ruth Armstrong 7.6.99
Response from author with revised manuscript 6.7.99
Editors' final decision - Ruth Armstrong 19.6.99

Date Comment

Wed Apr 21 11:33:25 1999 ESRF in Aborigines in NSW

1. The paper describes an important observation of difference in incidence and trends in ESRF between NSW & NT Aboriginals, and is worthy of publication.
· What are "experimental" population estimates (par 26)?
· What are the non-Aboriginal ESRF rates in NSW vs NT, i.e. is the NSW population healthier than the NT as a whole (par 29 & 44)? Without this data, the statement 'the incidence remains higher than among the Caucasian population" (par 40) is unsupported.
2. Table 2 (par 30 & 45) shows apparent differences between Aborigines and non-Aborigines in causes of primary renal diseases expressed as relative percentages.
· Is this NSW alone or all Australian aborigines?
· Do the lower incidences of PKD & reflux persist when expressed as absolute incidence per million population, i.e. when the swamping effect of diabetic nephropathy is removed?
· Is there a difference in rates of biopsy-proven renal disease, possibly relating to lack of access to a full range of specialist services?
3. Does Table 3 (demography & outcomes, par 31 & 46) refer to NSW alone or all Australian aboriginals? The lack of age-standardisation makes further interpretation difficult, particularly when assessing the "social" deaths (treatment withdrawal) which is usually seen in the elderly patient.
4. Transplant outcomes in NSW Aboriginal & non-Aboriginal patients showed equivalent, not lower, patient & graft survival rates (par 34, 39, 50 & 51), although Aboriginal patients were younger.
· Were there a different proportion of living vs cadaveric donors in Aboriginal vs non-Aboriginal patients, as another major confounder?
5. Some broad categories for the causes of the apparent differences in ESRF incidence between NT & NSW Aboriginals are discussed (par 40).
· Could the arbitrary definition of Aboriginality mask differences in Caucasian admixture in NSW?

Mark Thomas

Sat Apr 24 23:05:49 1999 NSW/NT/Aust ESRF

Cass & colleagues described difference in incidence & outcomes in ESRF between NSW & NT Aborigines. The results of their study are of general interest.

The authors postulated that the reported differences between NSW and NT aborigines were due to locations and social conditions. I wonder if the authors could provide some results of ESRF incidence and outcomes of different location groups (eg. out-reach, rural & city) within the States examined.

W.Wang

Tue Apr 27 00:16:37 1999 Thankyou for the above comments. In response to M.Thomas using your points:
1. Experimental population estimates and projections are the official Australian Bureau of Statistics estimates of populations in the years between censuses. The estimates work backwards from a census year i.e estimating 1992-5 from the 1996 census and projections are calculated for 1997-2006 from the 1996 census. The incidence rates are higher in both states when compared to non-Ab from ANZDATA figures. The NT non-Ab population has lower ESRD incidence than NSW or Australia as a whole because it is a younger population.
2. Table 2 is a comparison for NSW alone. I agree to express incidence as a rate in persons per million would be optimal but the absolute numbers are too small for APCKD and reflux: 1 per 10 years.
A greater percentage of Ab have an uncertain diagnosis probably indicating a lower biopsy rate.
3. Table 3 refers to NSW alone. Numbers are again very small but we tried to make the point strongly that the Ab patients were significantly younger.
4. The point estimates of 1 and 5 year patient and graft survival are lower for Ab than non-Ab, thus outcomes are not equivalent. I agree that with the large 95% CI and non-significant log rank test we do not have evidence that they are significantly different. ANZDATA figures show a lower proportion of living related donors among Ab.
5. The definitions of Aboriginality are according to ANZDATA and ABS: people who identify themselves as Aboriginal. This definition is relied upon for Australian medical and social science literature. The effects of racial intermingling may be made clearer by comparison of patterns of disease between different regions within the state. We plan to look at this issue in further research despite the fact that numbers will be very small and require aggregation of several years. This also indicates in response to W. Wang that we hope to answer your question in the near future.
Alan Cass

Mon May 3 10:53:58 1999 Review of ESRF in Aborigines in NSW: demography and outcomes 1987 - 1998.

This interesting manuscript describes the incidence and outcome of renal disease in Aborigines in NSW compared to the Northern Territory experience. Its central finding is that rates of renal failure in Aborigines in NSW have remained stable in contrast to the Northern Territory experience. In some ways this is an unexpected finding and as such it is worthy of publication. It also provokes an important discussion about the most effective method of providing renal replacement therapy to these populations.

Point 1: The study is based on secondary data review and to that extent the findings are dependent on the accuracy and consistency of the data that have been collected. The issue of the problem of classification of Aboriginality has already been discussed in this forum. It would seem that the ABS experimental estimates probably provide the best estimate of the Aboriginal population in each state bearing in mind the limitations mentioned by the authors. The other aspect of data collection worthy of comment is whether there may be differences in entry into ANZDATA in each state. Although ESRF is a fairly definite endpoint, an apparent increase in the rate of ESRF could in part be due to a tendency to commence dialysis at a lower creatinine now than previously was the case. Is there any evidence that patients are being entered into dialysis programmes at an earlier stage in NT compared to NSW? Is there any evidence that dialysis was commenced at an earlier stage of renal failure in 1998 compared to a decade ago? (par 24 - par 25)

Point 2: I have some concerns about the inferences based on the statistical analysis of data in the NSW Ab vs non-Ab groups. The failure to detect differences in mortality or transplant outcomes may simply be a beta-error due to the relatively small sample size of the NSW Ab group (par 46, table 3).

Point 3: The authors cite several reasons for the apparent differences in the NSW and NT experiences of ESRF in the Ab population, for example cultural differences and differences in urbanisation (par 38). Are there also differences in the incidence and prevalence of NIDDM between these populations? Does the epidemic of ESRF in the NT Ab population simply reflect an increase in the prevalence of NIDDM in this population or are NT Ab more susceptible to the nephropathic effects of NIDDM than NSW Ab?

John Kelly

Tue May 4 12:01:26 1999 In response to John Kelly's comments (using your numbers):
1) There is no definite evidence available to answer this question. ANZDATA has started collecting data regarding Creat Clearance at time of entry during the last 12 months only. There is a debate occurring NOW amongst nephrologists regarding starting dialysis based upon renal clearance tests rather than waiting for a patient to develop uraemic symptoms. The typical problem amongst Aboriginal patients has been one of late presentation rather than early treatment. If guicelines regarding commencement of dialysis are promulgated, it would only result in a incremental shift forward in treatment of a few months. This should not affect incidence rates significantly.
2) I agree. I hope we have expressed in the manuscript that the small numbers (especially of transplants) may obscure a real difference in outcomes.
3) The epidemic of disease in the NT, on availble evidence, is not only due to an increased prevalence of NIDDM. Community screening studies by Van Buynder (1989) and ongoing work by Hoy on the Tiwi Islands show prevalence of significant proteinuria significantly in excess of the prevalence of impaired glucose tolerance and overt diabetes. Hoy (1995) showed that the the average annual incidence for 1988-93, in the NT, of ESRD NOT attributable to diabetes was 350/million/year. This is significantly greater than the total average annual incidence for NSW Aborigines (static at about 110-115/million/year from our article).

Alan Cass

Fri May 14 12:36:06 1999 Statistical review

The key methodological issue for this paper is whether the differences between NSW and NT could be due to problems with the data. I think the authors should provide more information on this issue.

For example, How are Aborigines are identified in ANZDATA and could this differ between NT and NSW? (e.g., is it self-identification or does the treating doctor decide whether the person is Aboriginal?)

Also, there was a large increase in the number of people who identified as Indigenous in the 1996 Census and this affected the experimental estimates. The increase could not be explained by trends in fertility and the ABS has put it down to a greater propensity of people to identify as Indigenous. The increase was particularly marked in the urban areas of NSW, Queensland and Victoria. In NT the increase was less marked. This could have an effect on the trends over time and should be briefly mentioned in the paper as a possible source of error.

How complete is follow-up of patients in ANZDATA with respect to death and graft survival?

Michael Coory

Sat May 15 22:45:46 1999 In response to Michael Coory's comments:
1) Self identification is used in ANZDATA collections and there is no evidence that this method of identification differs between states.
2) We understand that there was a large increase in the number of people who identified as Indigenous at the 1996 Census and that this increase was particularly marked in NSW, but less in the NT. In this paper we used the most recent ABS experimental estimates for Indigenous populations as the denominators to calculate the incidence of ESRD. We used 1991 Census experimental estimates for 1988-91, 1996 Census experimental estimates for 1992-96, and 1996 Census high series projections for 1997. This was done consciously, as the estimates and projections are updated after each Census taking into account new available data. This decision to use the most recent figures, with substantially higher population figures for NSW, has NO fundamental impact upon the difference in the patterns of incidence of ESRD between the NSW and NT.
If we had used 1991 Census high series population projections as the denominators, the divergent pattern of incidence remains. The NSW incidence would rise from 118/million/year in 1988-89 to 150/million/year in 1996-97. This represents an increase of 27% over the decade. The NT incidence would rise from 255/million/year in 1988-89 to 851/million/year in 1996-97. This represents an increase of 234% over the decade. The basic finding of differences between NSW and NT remains unchallenged.
3) ANZDATA follow up is virtually complete with regard to deaths and graft failure. Graft failure results in the need to recommence dialysis or death. Death means the cessation of dialysis or cessation of provision of immunosuppressive drugs. These services are provided almost exclusively in Australia by hospital based nephrology units, who provide 6 monthly reports to ANZDATA.
Alan Cass

Mon Jun 7 14:10:17 1999 Editorial comments and outcome of the editorial meeting

Thank-you all for participating in the Internet peer-review process and thanks to the authors for their rapid responses to some of the questions raised by the reviewers. The final reviewer has informed us that he is currently unable to provide us with written comments so we have decided to proceed with the available information. The manuscript was discussed at our June 3 editorial committee meeting. We think this is an interesting paper which, pending satisfactory revision, should be worthy of publication.

In revising the paper we would like you to consider the following;
ANZDATA is never clearly defined. You should do this and briefly describe their data sources etc.
The abstract is not in the structured style which is acceptable to the Journal. It should contain the headings Objectives, design, methods, main outcome measures, results and conclusion.
In your METHODS section, you mention the sources of the NSW and the national figures, but not the NT figures. This should be clearly spelt out.
The question of larger numbers of people self-identifying as Aboriginal in the '96 census is interesting one which deserves discussion in the revised paper.
In revising the manuscript, please take all the referees comments into account. Many of your answers should be worked into the manuscript to clarify your methods and results and to enhance your discussion,
Please provide 95% confidence intervals in the tables. You need to rethink the title, to reflect the fact that these are data which compare NSW with national figures and with the NT.

If you are happy to address all these issues we would like to see your revised manuscript on the web by July 19 1999. Please provide a covering statement on your changes in response to the referees and highlight your changes in some way.

If the referees have any other comments in the interim or wish to comment on the revised version, this would be welcome.
Thanks again everyone for your contributions.

Ruth Armstrong
Ruth Armstrong

Tue Jul 6 14:27:01 1999 I am attaching the revised manuscript "End stage renal disease in Aborigines in New South Wales: A very different picture to the Top End". The following changes have been made as per your letter of 7 June 1999:
* ANZDATA is clearly defined in the abstract and their data sources in the methods section.
* The abstract is in the structured style suggested in the MJA Advice to Authors document.
* ANZDATA is mentioned as the source of the NT figures in the methods section.
* The definitions of "Aboriginality" and increasing propensity for people to self-identify as Aborigines are discussed in the methods section.
* The title has been changed.
I have not included 95% confidence intervals in the tables. Tables 1-3 are descriptive tables using actual numbers of patients or percentages, and Census based population estimates. 95% CIs are not appropriate in this context. 95% CIs are appropriate for figures 3 and 4. However, they have been detailed explicitly in the results section and would make the figures very hard to interpret if included graphically.
I have revised the article in response to the comments made by the reviewers.

M. Thomas:
1. Population estimates described in methods section and non-Aboriginal ESRD rate for NSW mentioned in results section.
2. Possible lower renal biopsy rate mentioned in discussion section.
3. Table 3 reference to NSW alone made explicit.

J. Kelly:
4. Possible effect of increased prevalence of NIDDM in NT explored in discussion section.

I hope these revisions are sufficient.
Yours sincerely,

Alan Cass
Menzies School of Health Research
Darwin, NT.

Alan Cass

Mon Jul 19 18:25:18 1999 Editorial decision on the revised manuscript
Ruth Armstrong
Assistant Editor
MJA

The revised manuscript "End stage renal disease in Aborigines in NSW: A very different picture to the Top End" was discussed at today's editorial committee meeting. The manuscript has been enhanced by revision and is now at a stage at which we can accept it for publication. We take your point on the issue of 95% confidence intervals and are willing to accept your current presentation of the results as long as the statistical reviewer, Dr Coory, is happy.

Initial publication will occur on the internet site within the next few days and the manuscript will be edited for print publication over the next few months.

Thanks again everyone for your participation.
Ruth Armstrong

Date	Comment
Wed Apr 21 11:33:25 1999	ESRF in Aborigines in NSW 1. The paper describes an important observation of difference in incidence and trends in ESRF between NSW & NT Aboriginals, and is worthy of publication. · What are "experimental" population estimates (par 26)? · What are the non-Aboriginal ESRF rates in NSW vs NT, i.e. is the NSW population healthier than the NT as a whole (par 29 & 44)? Without this data, the statement 'the incidence remains higher than among the Caucasian population" (par 40) is unsupported. 2. Table 2 (par 30 & 45) shows apparent differences between Aborigines and non-Aborigines in causes of primary renal diseases expressed as relative percentages. · Is this NSW alone or all Australian aborigines? · Do the lower incidences of PKD & reflux persist when expressed as absolute incidence per million population, i.e. when the swamping effect of diabetic nephropathy is removed? · Is there a difference in rates of biopsy-proven renal disease, possibly relating to lack of access to a full range of specialist services? 3. Does Table 3 (demography & outcomes, par 31 & 46) refer to NSW alone or all Australian aboriginals? The lack of age-standardisation makes further interpretation difficult, particularly when assessing the "social" deaths (treatment withdrawal) which is usually seen in the elderly patient. 4. Transplant outcomes in NSW Aboriginal & non-Aboriginal patients showed equivalent, not lower, patient & graft survival rates (par 34, 39, 50 & 51), although Aboriginal patients were younger. · Were there a different proportion of living vs cadaveric donors in Aboriginal vs non-Aboriginal patients, as another major confounder? 5. Some broad categories for the causes of the apparent differences in ESRF incidence between NT & NSW Aboriginals are discussed (par 40). · Could the arbitrary definition of Aboriginality mask differences in Caucasian admixture in NSW? Mark Thomas
Sat Apr 24 23:05:49 1999	NSW/NT/Aust ESRF Cass & colleagues described difference in incidence & outcomes in ESRF between NSW & NT Aborigines. The results of their study are of general interest. The authors postulated that the reported differences between NSW and NT aborigines were due to locations and social conditions. I wonder if the authors could provide some results of ESRF incidence and outcomes of different location groups (eg. out-reach, rural & city) within the States examined. W.Wang
Tue Apr 27 00:16:37 1999	Thankyou for the above comments. In response to M.Thomas using your points: 1. Experimental population estimates and projections are the official Australian Bureau of Statistics estimates of populations in the years between censuses. The estimates work backwards from a census year i.e estimating 1992-5 from the 1996 census and projections are calculated for 1997-2006 from the 1996 census. The incidence rates are higher in both states when compared to non-Ab from ANZDATA figures. The NT non-Ab population has lower ESRD incidence than NSW or Australia as a whole because it is a younger population. 2. Table 2 is a comparison for NSW alone. I agree to express incidence as a rate in persons per million would be optimal but the absolute numbers are too small for APCKD and reflux: 1 per 10 years. A greater percentage of Ab have an uncertain diagnosis probably indicating a lower biopsy rate. 3. Table 3 refers to NSW alone. Numbers are again very small but we tried to make the point strongly that the Ab patients were significantly younger. 4. The point estimates of 1 and 5 year patient and graft survival are lower for Ab than non-Ab, thus outcomes are not equivalent. I agree that with the large 95% CI and non-significant log rank test we do not have evidence that they are significantly different. ANZDATA figures show a lower proportion of living related donors among Ab. 5. The definitions of Aboriginality are according to ANZDATA and ABS: people who identify themselves as Aboriginal. This definition is relied upon for Australian medical and social science literature. The effects of racial intermingling may be made clearer by comparison of patterns of disease between different regions within the state. We plan to look at this issue in further research despite the fact that numbers will be very small and require aggregation of several years. This also indicates in response to W. Wang that we hope to answer your question in the near future. Alan Cass
Mon May 3 10:53:58 1999	Review of ESRF in Aborigines in NSW: demography and outcomes 1987 - 1998. This interesting manuscript describes the incidence and outcome of renal disease in Aborigines in NSW compared to the Northern Territory experience. Its central finding is that rates of renal failure in Aborigines in NSW have remained stable in contrast to the Northern Territory experience. In some ways this is an unexpected finding and as such it is worthy of publication. It also provokes an important discussion about the most effective method of providing renal replacement therapy to these populations. Point 1: The study is based on secondary data review and to that extent the findings are dependent on the accuracy and consistency of the data that have been collected. The issue of the problem of classification of Aboriginality has already been discussed in this forum. It would seem that the ABS experimental estimates probably provide the best estimate of the Aboriginal population in each state bearing in mind the limitations mentioned by the authors. The other aspect of data collection worthy of comment is whether there may be differences in entry into ANZDATA in each state. Although ESRF is a fairly definite endpoint, an apparent increase in the rate of ESRF could in part be due to a tendency to commence dialysis at a lower creatinine now than previously was the case. Is there any evidence that patients are being entered into dialysis programmes at an earlier stage in NT compared to NSW? Is there any evidence that dialysis was commenced at an earlier stage of renal failure in 1998 compared to a decade ago? (par 24 - par 25) Point 2: I have some concerns about the inferences based on the statistical analysis of data in the NSW Ab vs non-Ab groups. The failure to detect differences in mortality or transplant outcomes may simply be a beta-error due to the relatively small sample size of the NSW Ab group (par 46, table 3). Point 3: The authors cite several reasons for the apparent differences in the NSW and NT experiences of ESRF in the Ab population, for example cultural differences and differences in urbanisation (par 38). Are there also differences in the incidence and prevalence of NIDDM between these populations? Does the epidemic of ESRF in the NT Ab population simply reflect an increase in the prevalence of NIDDM in this population or are NT Ab more susceptible to the nephropathic effects of NIDDM than NSW Ab? John Kelly
Tue May 4 12:01:26 1999	In response to John Kelly's comments (using your numbers): 1) There is no definite evidence available to answer this question. ANZDATA has started collecting data regarding Creat Clearance at time of entry during the last 12 months only. There is a debate occurring NOW amongst nephrologists regarding starting dialysis based upon renal clearance tests rather than waiting for a patient to develop uraemic symptoms. The typical problem amongst Aboriginal patients has been one of late presentation rather than early treatment. If guicelines regarding commencement of dialysis are promulgated, it would only result in a incremental shift forward in treatment of a few months. This should not affect incidence rates significantly. 2) I agree. I hope we have expressed in the manuscript that the small numbers (especially of transplants) may obscure a real difference in outcomes. 3) The epidemic of disease in the NT, on availble evidence, is not only due to an increased prevalence of NIDDM. Community screening studies by Van Buynder (1989) and ongoing work by Hoy on the Tiwi Islands show prevalence of significant proteinuria significantly in excess of the prevalence of impaired glucose tolerance and overt diabetes. Hoy (1995) showed that the the average annual incidence for 1988-93, in the NT, of ESRD NOT attributable to diabetes was 350/million/year. This is significantly greater than the total average annual incidence for NSW Aborigines (static at about 110-115/million/year from our article). Alan Cass
Fri May 14 12:36:06 1999	Statistical review The key methodological issue for this paper is whether the differences between NSW and NT could be due to problems with the data. I think the authors should provide more information on this issue. For example, How are Aborigines are identified in ANZDATA and could this differ between NT and NSW? (e.g., is it self-identification or does the treating doctor decide whether the person is Aboriginal?) Also, there was a large increase in the number of people who identified as Indigenous in the 1996 Census and this affected the experimental estimates. The increase could not be explained by trends in fertility and the ABS has put it down to a greater propensity of people to identify as Indigenous. The increase was particularly marked in the urban areas of NSW, Queensland and Victoria. In NT the increase was less marked. This could have an effect on the trends over time and should be briefly mentioned in the paper as a possible source of error. How complete is follow-up of patients in ANZDATA with respect to death and graft survival? Michael Coory
Sat May 15 22:45:46 1999	In response to Michael Coory's comments: 1) Self identification is used in ANZDATA collections and there is no evidence that this method of identification differs between states. 2) We understand that there was a large increase in the number of people who identified as Indigenous at the 1996 Census and that this increase was particularly marked in NSW, but less in the NT. In this paper we used the most recent ABS experimental estimates for Indigenous populations as the denominators to calculate the incidence of ESRD. We used 1991 Census experimental estimates for 1988-91, 1996 Census experimental estimates for 1992-96, and 1996 Census high series projections for 1997. This was done consciously, as the estimates and projections are updated after each Census taking into account new available data. This decision to use the most recent figures, with substantially higher population figures for NSW, has NO fundamental impact upon the difference in the patterns of incidence of ESRD between the NSW and NT. If we had used 1991 Census high series population projections as the denominators, the divergent pattern of incidence remains. The NSW incidence would rise from 118/million/year in 1988-89 to 150/million/year in 1996-97. This represents an increase of 27% over the decade. The NT incidence would rise from 255/million/year in 1988-89 to 851/million/year in 1996-97. This represents an increase of 234% over the decade. The basic finding of differences between NSW and NT remains unchallenged. 3) ANZDATA follow up is virtually complete with regard to deaths and graft failure. Graft failure results in the need to recommence dialysis or death. Death means the cessation of dialysis or cessation of provision of immunosuppressive drugs. These services are provided almost exclusively in Australia by hospital based nephrology units, who provide 6 monthly reports to ANZDATA. Alan Cass
Mon Jun 7 14:10:17 1999	Editorial comments and outcome of the editorial meeting Thank-you all for participating in the Internet peer-review process and thanks to the authors for their rapid responses to some of the questions raised by the reviewers. The final reviewer has informed us that he is currently unable to provide us with written comments so we have decided to proceed with the available information. The manuscript was discussed at our June 3 editorial committee meeting. We think this is an interesting paper which, pending satisfactory revision, should be worthy of publication. In revising the paper we would like you to consider the following; ANZDATA is never clearly defined. You should do this and briefly describe their data sources etc. The abstract is not in the structured style which is acceptable to the Journal. It should contain the headings Objectives, design, methods, main outcome measures, results and conclusion. In your METHODS section, you mention the sources of the NSW and the national figures, but not the NT figures. This should be clearly spelt out. The question of larger numbers of people self-identifying as Aboriginal in the '96 census is interesting one which deserves discussion in the revised paper. In revising the manuscript, please take all the referees comments into account. Many of your answers should be worked into the manuscript to clarify your methods and results and to enhance your discussion, Please provide 95% confidence intervals in the tables. You need to rethink the title, to reflect the fact that these are data which compare NSW with national figures and with the NT. If you are happy to address all these issues we would like to see your revised manuscript on the web by July 19 1999. Please provide a covering statement on your changes in response to the referees and highlight your changes in some way. If the referees have any other comments in the interim or wish to comment on the revised version, this would be welcome. Thanks again everyone for your contributions. Ruth Armstrong Ruth Armstrong
Tue Jul 6 14:27:01 1999	I am attaching the revised manuscript "End stage renal disease in Aborigines in New South Wales: A very different picture to the Top End". The following changes have been made as per your letter of 7 June 1999: * ANZDATA is clearly defined in the abstract and their data sources in the methods section. * The abstract is in the structured style suggested in the MJA Advice to Authors document. * ANZDATA is mentioned as the source of the NT figures in the methods section. * The definitions of "Aboriginality" and increasing propensity for people to self-identify as Aborigines are discussed in the methods section. * The title has been changed. I have not included 95% confidence intervals in the tables. Tables 1-3 are descriptive tables using actual numbers of patients or percentages, and Census based population estimates. 95% CIs are not appropriate in this context. 95% CIs are appropriate for figures 3 and 4. However, they have been detailed explicitly in the results section and would make the figures very hard to interpret if included graphically. I have revised the article in response to the comments made by the reviewers. M. Thomas: 1. Population estimates described in methods section and non-Aboriginal ESRD rate for NSW mentioned in results section. 2. Possible lower renal biopsy rate mentioned in discussion section. 3. Table 3 reference to NSW alone made explicit. J. Kelly: 4. Possible effect of increased prevalence of NIDDM in NT explored in discussion section. I hope these revisions are sufficient. Yours sincerely, Alan Cass Menzies School of Health Research Darwin, NT. Alan Cass
Mon Jul 19 18:25:18 1999	Editorial decision on the revised manuscript Ruth Armstrong Assistant Editor MJA The revised manuscript "End stage renal disease in Aborigines in NSW: A very different picture to the Top End" was discussed at today's editorial committee meeting. The manuscript has been enhanced by revision and is now at a stage at which we can accept it for publication. We take your point on the issue of 95% confidence intervals and are willing to accept your current presentation of the results as long as the statistical reviewer, Dr Coory, is happy. Initial publication will occur on the internet site within the next few days and the manuscript will be edited for print publication over the next few months. Thanks again everyone for your participation. Ruth Armstrong