Table 1.

QUADAS quality assessment checklist applied to MRCP studies

Study	1. Patient spectrum	2. Selection criteria	3. Reference standard	4. Time period	5. Verification bias	6. Same RS	7. RS independent of IT	8. IT described in detail	9. RS described in detail	10. IT interpreted without RS	11. RS interpreted without IT	12. All clinical data	13. All test results	14. Withdrawals
Adamek[9]	yes	yes	yes	unclear	no	yes	N/a	yes	no	yes	yes	yes	Yes	yes
Angulo[11]	yes	yes	unclear	yes	no	yes	N/a	yes	no	yes	yes	no	Yes	yes
Barish[12]	yes	yes	unclear	yes	no	yes	N/a	yes	no	yes	unclear	no	yes	yes
Calvo[13]	unclear	yes	unclear	no	no	yes	N/a	yes	unclear	yes	unclear	yes	Yes	yes
Chan[14]	yes	unclear	unclear	yes	no	yes	N/a	yes	unclear	yes	yes	no	Yes	yes
Demartines [15]	yes	yes	unclear	unclear	no	yes	N/a	yes	yes	yes	yes	no	no	no
Dwerryhouse[16]	unclear	yes	unclear	no	no	yes	N/a	yes	no	unclear	yes	unclear	Yes	yes
Guibaud [18]	yes	yes	unclear	no	no	yes	N/a	yes	no	yes	yes	no	Yes	yes
Holzknecht[20]	unclear	yes	unclear	no	no	yes	N/a	yes	yes	yes	yes	unclear	Yes	yes
Laokpessi [21]	no	yes	yes	yes	no	yes	N/a	yes	no	yes	unclear	unclear	Yes	yes
Lee[22]	yes	yes	yes	no	no	yes	N/a	yes	yes	yes	yes	unclear	No	yes
Lomanto [23]	yes	unclear	unclear	unclear	no	yes	N/a	yes	no	unclear	unclear	unclear	No	no
Lomas[24]	yes	yes	unclear	yes	no	yes	N/a	yes	yes	no	no	yes	Yes	yes
Macaulay [25]	yes	unclear	yes	no	no	yes	N/a	yes	no	yes	unclear	no	No	no
Regan[26]	yes	unclear	yes	yes	no	yes	N/a	yes	no	yes	unclear	unclear	Yes	yes
Reinhold [27]	yes	yes	unclear	no	no	yes	N/a	yes	no	Yes	unclear	yes	Yes	yes
Soto 1996[28]	no	unclear	unclear	yes	no	yes	N/a	yes	no	Yes	unclear	no	No	unclear
Soto 2000b[29]	yes	yes	unclear	no	no	yes	N/a	yes	unclear	Yes	yes	no	Yes	yes
Soto 2000a[30]	yes	yes	unclear	no	no	yes	N/a	yes	unclear	Yes	yes	no	Yes	yes
Stiris[31]	yes	unclear	unclear	yes	yes	yes	N/a	yes	no	yes	yes	unclear	Unclear	unclear
Sugiyama[32]	unclear	no	unclear	no	no	yes	N/a	yes	no	no	yes	yes	Yes	yes
Taylor[33]	yes	yes	unclear	yes	no	yes	N/a	yes	no	Yes	yes	unclear	Yes	yes
Textor[34]	yes	unclear	unclear	no	no	yes	N/a	yes	yes	Yes	unclear	no	Yes	yes
Varghese [35]	unclear	unclear	unclear	no	no	yes	N/a	yes	yes	yes	yes	yes	Yes	yes
Zidi[36]	yes	no	unclear	yes	no	yes	N/a	yes	yes	Yes	unclear	no	No	no

RS = reference standard (ERCP); IT = index test (MRCP).

QUADAS Questions

1. Was the spectrum of patients representative of the patients who will receive the test in practice?

2. Were selection criteria clearly described?

3. Is the reference standard likely to correctly classify the target condition?

4. Is the time period between reference standard and index test short enough to be reasonably sure that the target condition did not change between the two tests?

5. Did the whole sample or a random selection of the sample, receive verification using a reference standard of diagnosis?

6. Did patients receive the same reference standard regardless of the index test result?

7. Was the reference standard independent of the index test (i.e. the index test did not form part of the reference standard?

8. Was the execution of the index test described in sufficient detail to permit replication of the test?

9. Was the execution of the reference standard described in sufficient detail to permit its replication?

10. Were the index test results interpreted without knowledge of the results of the reference standard?

11. Were the reference standard results interpreted without knowledge of the results of the index test?

12. Were the same clinical data available when test results were interpreted as would be available when the test is used in practice?

13. Were uninterpretable/intermediate test results reported?

14. Were withdrawals from the study explained?