Deveney 1984.

Study characteristics
Patient sampling	Country USA Study design Prospective Setting Hospital Dates of data collection starting in 1978 Population (n) N/R Inclusion criteria Resection for curable adenocarcinoma of the colon or rectum Exclusion criteria Dukes D Participants included (n) 65
Patient characteristics and setting	Age range 67 yrs mean Smoking status N/R Site of primary tumour Colorectal Stage of primary tumour 8 Dukes A tumours, 34 had Dukes B tumours, and 20 had Dukes C tumours Perioperative investigations done to ensure no residual disease N/R Chemotherapy/radiotherapy? Some got radio/chemotherapy Recurrences (n) 23 Site of recurrences N/R
Index tests	CEA timing 3‐monthly in yr 1, then 6‐monthly to year 5 CEA technique N/R CEA threshold 5 µg/L Definition of positive 1 elevated value Which CEA value (s) used? All
Target condition and reference standard(s)	Follow‐up schedule 3‐monthly in year 1, then 6‐monthly to year 5: clinical history, examination, FOBT, LFT, CEA. 6‐monthly CXR, CT abdomen, total colonoscopy. BE at 6 and 12 months then annually Reference standard A positive finding on any test prompted additional confirmatory tests, including laparotomy, thoracotomy,or percutaneous CT‐directed biopsy
Flow and timing	Timing of CEA vs reference standard (days) per protocol
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?	Yes
Did the study avoid inappropriate exclusions?	Yes
		Low	Low
DOMAIN 2: Index Test All CEA thresholds
If a threshold was used, was it pre‐specified?	Yes
Is the same method and instrument used for all CEA measurements?	Unclear
Is there an estimation of reproducibility of the method, for example the % coefficient of variation at specific concentrations?	No
Is there an indication of method accuracy, for example, is there evidence of participation in an external quality assessment and proficiency testing scheme?	No
		Unclear	Low
DOMAIN 3: Reference Standard
Is the reference standards likely to correctly classify the target condition?	Yes
Were the reference standard results interpreted without knowledge of the results of the index tests?	No
		Low	Low
DOMAIN 4: Flow and Timing
Did all patients receive the same reference standard?	No
Were all patients included in the analysis?	Yes
Was the index test repeated prior to the reference standard?	No
Was the the timing between index test(s) and reference standard ascertainable?	No
Did all patients receive a reference standard?	Yes
		Low