Laitala 2017.

Study characteristics
Patient Sampling	Method of sampling: consecutive; "All 18–30‐year‐old university students" Included conditions: unclear Teeth: permanent premolars and molars Sealants: not reported Restorations: not reported Surface: approximal
Patient characteristics and setting	Age: 18 to 30 years Sex: not reported Ethnicity: not reported Country: Finland Setting: routine examination in dental clinic Number of participants/teeth/sites: 137 participants, of these 91 resulted in data, 1162 teeth, 2103 surfaces Prevalence: enamel 0.20, dentine 0.06 (according to radiograph results)
Index tests	Category of test: DIFOTI method Sequence of test(s): visual, radiograph, DIFOTI all recorded clinically and viewed after the event by different clinicians but uncertain whether same examiner performed each test or whether tests could be influenced by others Examiner training and calibration: trained by representatives of device manufacturer Threshold applied: "Score 0 = no caries; Score 1 = caries lesion in outer surface of the enamel; Score 2 = caries lesion extending into the inner enamel or dento‐enamel junction; Score 3 = dentinal caries lesion in the external half of dentin; Score 4 = deep dentinal caries lesion extending into the dentin half near the pulp" Device specifics: not reported
Target condition and reference standard(s)	Category: radiograph Sequence of index test and reference standard: visual then radiograph performed and interpreted separately to DIFOTI (index test) Training of examiner: experienced examiner in consensus Blinding to index test: yes Multiple tests: visual and radiograph performed before to index test Site selection: all surfaces Target condition: sound, initial and manifested
Flow and timing	Participants with index test but no reference standard: 0 Participants with reference standard but no index test: possibly there is a difference in numbers that received DIFOTI and other tests, 2083 versus 2103, but unclear how this was dealt with Time interval between tests: minimal Participants receiving both tests but excluded from results: 0
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
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	Unclear
Could the selection of patients have introduced bias?		Unclear risk
Are there concerns that the included patients and setting do not match the review question?			Low concern
DOMAIN 2: Index Test (All tests)
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?	Yes
If multiple tests were applied were different examiners used for each (in vivo)?	Yes
Could the conduct or interpretation of the index test have introduced bias?		Unclear risk
Are there concerns that the index test, its conduct, or interpretation differ from the review question?			Low concern
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
Could the reference standard, its conduct, or its interpretation have introduced bias?		High risk
Are there concerns that the target condition as defined by the reference standard does not match the question?			High
DOMAIN 4: Flow and Timing
Was there an appropriate interval between index test and reference standard?	Yes
Did all patients receive the same reference standard?	Unclear
Were all patients included in the analysis?	Unclear
Could the patient flow have introduced bias?		Low risk