Table 2 Classification of DRPs identified using PCNE v9.00 (N = 463)

Problems domain (total 463)

P1

The effectiveness of treatment

200(43.20)

P1.1

No effect of drug treatment

1(0.50)

P1.2

Effect of drug treatment not optimal

97(48.50)

P1.3

Untreated symptoms or indication

102(51.00)

P2

The safety of treatment

203(43.84)

P2.1

Adverse drug event (possibly) occurring

203(100.00)

P3

Other

60(12.96)

P3.1

Problem with cost-effectiveness of the treatment

20(33.33)

P3.2

Unnecessary drug-treatment

40(66.67)

Causes domain (total 463)

C1

Drug selection

279(60.26)

C1.2

Inappropriate drug (within guidelines but otherwise contraindicated)

88(31.54)

C1.3

No indication for drug

37(13.26)

C1.4

Inappropriate combination of drugs, or drugs and herbal medications, or drugs and dietary supplements

16(5.73)

C1.5

Inappropriate duplication of therapeutic group or active ingredient

9(3.23)

C1.6

No or incomplete drug treatment in spite of existing indication

119(42.65)

C1.7

Too many medicines prescribed for indication

10(3.58)

C2

Drug form

17(3.67)

C2.1

Inappropriate drug form for this patient

17(100.00)

C3

Dose selection

137(29.59)

C3.1

Drug dose too low

24(17.52)

C3.2

Drug dose too high

83(60.58)

C3.3

Dosage regimen not frequent enough

6(4.38)

C3.4

Dosage regimen too frequent

14(10.22)

C3.5

Dose timing instructions wrong, unclear or missing

10(7.30)

C4

Treatment duration

5(1.08)

C4.1

Too short treatment duration

2(40.00)

C4.2

Too long treatment duration

3(60.00)

C9

Other

25(5.40)

C9.1

No or inappropriate monitoring outcome (e.g., TDM)

25(100.00)