Chang 2011.

Study characteristics
Patient sampling	Type of study: retrospective study. Consecutive or random sample: neither.
Patient characteristics and setting	Sample size: 3451. Females: not stated. Median or median age: not stated. Presentation: Patients with acute abdominal pain and undergoing blood tests. Exclusion criteria Patients with parotid disease, intracranial haemorrhage, end‐stage renal failure. Setting: secondary care, Hong Kong, China.
Index tests	Index test: serum amylase. Further details: Technical specifications: Beckman Coulter chemistry analyser. Performed by: not stated. Criteria for positive diagnosis: > 3 times normal. Second criteria for positive diagnosis: > twice normal. Index test: serum lipase. Further details: Technical specifications: Beckman Coulter chemistry analyser. Performed by: not stated. Criteria for positive diagnosis: > 3 times normal. Second criteria for positive diagnosis: > twice normal.
Target condition and reference standard(s)	Target condition: acute pancreatitis. Reference standard: radiology (ultrasound or CT). Further details: Technical specifications: not stated. Performed by: not stated. Criteria for positive diagnosis: not stated.
Flow and timing	Number of indeterminates for whom the results of reference standard were available: not stated. Number of patients who were excluded from the analysis: not stated.
Comparative
Notes
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	No
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	No
		High	High
DOMAIN 2: Index Test Serum amylase
Were the index test results interpreted without knowledge of the results of the reference standard?	Unclear
If a threshold was used, was it pre‐specified?	Unclear
		Unclear	Low
DOMAIN 2: Index Test Serum Lipase
Were the index test results interpreted without knowledge of the results of the reference standard?	Unclear
If a threshold was used, was it pre‐specified?	Unclear
		Unclear	Low
DOMAIN 3: Reference Standard
Is the reference standards likely to correctly classify the target condition?	No
Were the reference standard results interpreted without knowledge of the results of the index tests?	Unclear
Is the reference standard independent of the index test?	Yes
		High	Low
DOMAIN 4: Flow and Timing
Was there an appropriate interval between index test and reference standard?	Unclear
Did all patients receive the same reference standard?	Yes
Were all patients included in the analysis?	Unclear
Did all patients receive a reference standard?	Yes
		Unclear