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. 2021 Oct 13;88(3):1235–1245. doi: 10.1111/bcp.15068

TABLE 3.

True positives and false positives per search strategy identifying ADRs

Number Search strategies Included trigger words TPs FPs PPV
n % n % %
S1 Keywords implying an ADR Conjugations of Drug‐induced 20 10 5 1 80
Allergy 17 8 80 21 18
Side effect 21 10 10 3 68
Intolerance 0 0 0 0 n/a
Reaction 1 0 2 1 33
Toxicity 13 6 1 0 93
S1 Total/overall ADRs found by keywords 72 35 98 26 42
S2a Prepositions followed closely b by a drug group c , a generic drug name, a drug brand, trade name or abbreviation a drug, or drug therapy d Conjugations of By 16 8 19 5 41
With 55 27 44 12 56
After 12 6 67 18 15
Of 31 15 62 16 33
On 5 2 73 19 6
Since 2 1 12 3 14
S2b Abbreviations using the included prepositions Conjugations of As a result of/because of 0 0 1 0 0
Based on 3 1 0 0 100
As a consequence of 4 2 1 0 80
S2 Total/overall ADRs found by a combination of predisposition and drug name 128 62 278 74 31
S3 Content of forms labelled a Conjugations of Allergies: 0 0 0 0 n/a
Conjugations of Anaphylaxis: 0 0 0 0 n/a
S3 Total/overall ADRs found in labelled allergy and anaphylaxis forms 0 0 0 0 n/a
S4 Content of complication registration containing key field drug‐induced 0 0 0 0 n/a
S5 Content of ADR module 6 3 0 0 100
S5 Total/overall ADRs found in ADR module 6 3 0 0 100
Total ADRs identified 206 100 377 100 35

Abbreviations: Adr, adverse drug reaction; FP, false positive; PPV, positive predicted value; TP, true positive.

a

Forms labelled allergy and anaphylaxis using free‐text entries were applied prior to the ADR module's introduction in 2015.

b

The maximum number of characters (ie, proximity between a preposition and drug name) was set at 16.

c

The drug group names were based on the Anatomical Therapeutic Chemical (ATC) therapeutic subgroup, pharmacological subgroup, chemical subgroup or chemical substance (ie, second to fifth levels of ATC main groups classified by WHO).

d

Examples are PPI (proton‐pump inhibitor), HCTZ (hydrochlorothiazide), FOLFOX (combination therapy of fluorouracil and oxaliplatin). A full list of abbreviations is provided in Table S2.