Figure 3 depicts a PRISMA diagram of record identification, screening, and inclusion. On the left hand side are a vertical row of 4 shaded boxes, top to bottom, Identification, Screening, Eligibility, and Included. In the middle of the figure is a vertical row of 7 boxes. The top box contains the words Records identified through data base searching (n = 1783). An arrow goes down to the next box, Records screened by title and abstract (Level I) (n = 1783). One arrow goes right from that box to a box, Records excluded at Level I (n = 1252). Another arrow goes down to the next box in the column, Full text articles assessed for eligibility (level I) (n = 538). An arrow goes from that box to the next, Records included at Level II (n = 204). An arrow goes from the arrow to that box to a large box on the right, Full text records excluded at level II. Reasons: (bullet list) Editorial, review, commentary, letter, news, report or case report (n = 44); Study population was not relevant (n = 159); Language of publication was not English (n = 2); Neither abstract nor full text could be retrieved (n = 11); Other reasons (n = 118). From the Records included at Level II (n = 204) box an arrow goes down to a box, Further full text eligibility assessment for key questions 1a and 1b by content experts (level III). An arrow goes down from that box to another box, Records included at level II (n = 169). From that arrow, another arrow goes right to a box, Full text records excluded at level II. Reasons: (bullet list) No direct pre-analytic data of relevance (n = 32); Non-original data (n = 1); No proficiency, reproducibility and precision data (n = 4*). From the Records included at level III box an arrow goes down to the bottom box, Records included in the report (n = 136 records of 115 unique studies). On either side of that box, and connected by an arrow that goes over the middle box, are two boxes. The box on the left is Studies included in quantitative syntheses (n = 45), and the box on the right is Eligible records not reporting relevant data for any key question (n = 33). On the bottom right is the explanation for the asterix, Two records had two primary reasons for exclusion at level III.

Figure 3PRISMA diagram of record identification, screening and inclusion

* Two records had two primary reasons for exclusion at level III

From: 3, Results

Cover of Assessment of Thiopurine Methyltransferase Activity in Patients Prescribed Azathioprine or Other Thiopurine-Based Drugs
Assessment of Thiopurine Methyltransferase Activity in Patients Prescribed Azathioprine or Other Thiopurine-Based Drugs.
Evidence Reports/Technology Assessments, No. 196.
Booth RA, Ansari MT, Tricco AC, et al.

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