Review for 10.1186/s12876-015-0398-8 (2015)

Reviewer's report
Title:Title: Comparison of medical costs generated by IBS patients in primary
and secondary care in the Netherlands
Version:2Date:23 July 2015
Reviewer: Elaine Harkness
Reviewer's report:
This article provides a comparison of costs in patients with IBS in primary and
secondary care settings. The paper is well organised and written. It concludes
that medical costs of IBS are much higher when patients are treated within
secondary care and that for optimisation of healthcare resources IBS should be
treated within primary care where possible.
Major revisions
1) Is the prevalence rate of IBS within the primary care population as expected?
The authors should discuss the use of the diagnostic code for IBS within primary
care. We have recently reported that GPs are reluctant to use the diagnostic
code for IBS until more serious conditions are ruled out and that there is often a
delay in adding the diagnostic code to the patient record until GPs are confident
of the diagnosis (see ref below). Thus, codes such as ‘abdominal pain’,
‘diarrhoea’ or ‘constipation’ remain on the patient record, rather than IBS. Is this
likely to be an issue within the Netherlands and if so did the authors consider
other symptom/diagnostic codes that may have been used instead of IBS?
Harkness EF, Harrington V, Hinder S, O’Brien SJ, Thompson DG, Beech P et al:
GP perspectives of
irritable bowel syndrome - an accepted illness, but management deviates from
guidelines: a qualitative study. BMC Fam Pract 2013, 14:92.
2) Were prescription-based data only for those patients identified as having an
IBS diagnostic code in primary care? If so, it’s possible that medication codes in
the primary care database may identify other patients who potentially have IBS
but without specifically having an IBS diagnosis. This should be discussed further
in the text.
Minor revisions
1) Line 66: the authors mention ‘For controls there was no significant difference
before and after diagnosis’ which is confusing – it would be better to refer to an
index date or date of pseudo-diagnosis. It is also not clear what they are referring
to when they say no significant difference.
2) Line 138: change ‘ensured with…’ to ‘insured with’
3) Line 125: define the acronym ICPC
4) Line 134: Patient selection: please clarify which diagnostic or symptom codes
were used to identify patients with IBS - is it IBS alone or were other
symptom/diagnostic codes considered?
5) Line 144: change ‘twice the size, age- and gender-matched control group…’ to
‘two age- and gender-matched controls….’
6) Line 151: Study period: The authors say to ensure primary care patients were
not subsequently referred to a hospital those who were diagnosed during the last
year of the study were excluded…how many patients were excluded for this
reason?
7) Line 259: add that the largest portion of increase in medication costs was due
to ‘All other drugs’ i.e. category 8 of Table 5. In Table 5 please define what ‘Other
ATC group N drugs’ and ‘Other ATC group A drugs’ are/cover?
8) Line 266: should the increase in proportion of total health care costs in primary
care costs for IBS not be 29% rather than 35%?
9) Line 338: I’m not sure what is meant by the term ‘strict indications’
Results
10) The results of the comparisons between primary and secondary care are
interesting but I think it would also be interesting to compare primary care
patients with the primary care controls and similarly secondary care patients with
secondary care controls. As the paper is written at the moment I’m not sure of
the benefit of including the control data as the results primarily draw on the cost
differences between primary and secondary care.
11) The number of GP contacts are expressed to one decimal place in the results
section but to no decimal places in the Table 3. Please add one decimal place to
Table 3. Was any statistical test performed to determine whether there were
differences in GP contacts for primary and secondary care patients? If so,
p-values should be added to Table 3.
12) For the healthcare costs the authors use the mean and standard deviations
for reporting the results despite the cost data being skewed – this is mentioned in
the discussion and the reason for doing so. The results for the GP contacts are
also expressed in means and standard deviations is this for the same reason i.e.
that the medians might be very low or zero?
Discretionary revisions
13) Line 53: change ‘Compare cost and magnitude’ to ‘To compare the costs and
magnitude…’
14) Line 63: change (+2328 Euro and +486 Euro) to (+2328 Euro and +486 Euro
respectively)
15) Line 65: add ‘but’ before ‘not for GP contacts’
16) Line 68: ‘after diagnosis of IBS is set’ sounds odd perhaps ‘is established’ or
‘is determined’ would sound better.
17) Line 70: change ‘as much as possible…’ to ‘where possible’
18) Line 204: change ‘For a specification of…’ to ‘For a breakdown of…’
19) Line 232: Annual hospital specialist care costs before and after IBS diagnosis
– I found the first few sentences of this section hard to follow because they refer
to different tables (2 & 4). On reading again I realised that the first sentence is in
relation to total costs for specialist care whilst the third sentence is in relation to
IBS specific costs in secondary care – I think this could be made clearer in the
text.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a statistician.
Declaration of competing interests:
I declare I have no competing interests