In those new MRG models all patients of a cer-
tain practice are classified and a specific structure for
each practice is the result. As an example, we consider
a physician with 14.0 % of his patients in the MRG
A10A (Insulins and analogues) and 11.8 % patients in
the MRG V04C (other diagnostic agents = test strips
measuring glucose). In this group of general practi-
tioners (GP) patients in those groups only account for
3.8 % in these two groups. The physician can thereby
be identified as a diabetologist:
Table 5: Patient structure of a diabetologist.
nr MRG nr. cost per prop. prop. drug droup
pat. patient doc. group
1 A10A 193 463.12 14.0% 2.4% Insulins and analo-
gues
2 V04C 162 307.76 11.8% 1.4% Other diagnostic
agents
3 H03A 86 22.28 6.3% 4.5% Thyroid preparations
4 A10B 82 185.78 6.0% 2.7% Oral blood glucose
lowering drugs
5 A02B 73 60.91 5.3% 7.2% Drugs for peptic
ulcer and gastro-
oesophageal reflux
disease (gord)
6 B01A 53 366.21 3.9% 4.0% Antithrombotic
agents
1 J01D 22 31.70 1.6% 2.4% Other beta-lactam
antibacterials
19 C10A 17 58.30 1.2% 3.0% Cholesterol and tri-
glyceride reducer
20 N03A 16 275.63 1.2% 1.4% Antiepileptics
After the formation of groups for all practi-
ces/physicians one can compare the MRG distributi-
ons and values in each group:
Table 6: MRG patient shares of orthopaedics.
frac. cost MRG drug group
pat. p. pat.
42.9% 19.95 M01A Antiinflammatory and antirheumatic products,
non-steroids
13.6% 26.26 H02A Corticosteroids for systemic use, plain
12.4% 23.81 N02B Other analgesics and antipyretics
8.2% 134.66 M05B Drugs affecting bone structure and mineraliza-
tion
6.1% 123.78 N02A Opioids
3.6% 92.18 B01A Antithrombotic agents
3.3% 40.71 M03B Muscle relaxants, centrally acting agents
2.5% 33.75 A02B Drugs for peptic ulcer and gastro-oesophageal
reflux disease (gord)
1.1% 2,515.02 L04A Immunosuppressive agents
1.0% 304.63 L01B Antimetabolites
Regarding orthopedics we observe a patient type
structure, in which 42.9 % of all patients belong to
the MRG M01A (antiinflammatory and antirheuma-
tic products, non-steroids). The 10 leading positions
cover 94.6 % of the costs. Costs again depend mainly
on the medical discipline. In oncology average costs
per patient are 15,288.17 e in the MRG L04A (im-
munosuppressive agents including all the other drugs
for the patient) versus 2,515.02 e for orthopedics. In
urology the top ten positions with respect to the num-
ber of patients cover 83.6 % of the costs. In the case
of GP these costs are only 44.2 %:
Table 7: MRG patient shares of urologists.
frac. cost MRG drug group
pat. p. pat.
34.8% 44.67 G04C Drugs used in benign prostatic hypertrophy
16.7% 136.12 G04B Other urologicals, incl. antispasmodics
9.9% 19.84 J01M Quinolone antibacterials
6.8% 618.61 L02A Hormones and related agents
4.9% 30.42 J01X Other antibacterials
3.1% 33.47 J01D Other beta-lactam antibacterials
2.0% 154.56 G03B Androgens
1.9% 22.13 J01E Sulfonamides and trimethoprim
1.7% 27.71 D01A Antifungals for topical use
1.7% 4,122.10 L02B Antimetabolites
Table 8: MRG patient shares of general practitioners.
frac. cost MRG drug group
pat. p. pat.
7.3% 62.55 A02B Drugs for peptic ulcer and gastro-oesophageal
reflux disease (gord)
5.4% 42.04 C07A Beta blocking agents
5.1% 34.67 M01A Antiinflammatory and antirheumatic products,
non-steroids
4.7% 24.25 H03A Thyroid preparations
4.2% 185.14 R03A Adrenergics, inhalants
3.8% 316.40 B01A Antithrombotic agents
3.8% 124.59 C09D Angiotensin II antagonists, combinations
3.4% 85.10 C09C Angiotensin II antagonists, plain
3.4% 30.68 C09A Ace inhibitors, plain
3.2% 88.42 N06A Antidepressants
The MRG patient shares can be utilized to gene-
rate distance measures for the clustering of all practi-
ces/physicians. Let p
k
m
be the fraction of patients with
MRG m (m ∈ M) for the physician k (k ∈ P). With
respect to the medical discipline s (s ∈ S) and let q
s
m
be the respective fraction. Let r and s be such fracti-
ons for physicians or medical disciplines we can use
a Manhattan distance:
∑
i∈M
|r
i
−s
i
|
Alternatively we can apply spherical distances on the
n-dimensional sphere where n is the number of MRG
classes with respect to the points:
r
m
r
∑
j∈M
r
2
j
and
s
m
r
∑
j∈M
s
2
j
or
√
r
m
and
√
s
m
The spherical distances are differentiable with respect
to the components of r and s and thereby is more sui-
table for optimization procedures.
Comparison of Different Implementations of a Process Limiting Pharmaceutical Expenditures Required by German Law
39