Ko 2015.

Study characteristics
Patient Sampling	Method of sampling: selected Included conditions: severity of condition unclear, "proximal surfaces with extensive cavities involving more than half of the proximal surface were excluded" Teeth: permanent molars and premolars Sealants: not reported Surface: approximal
Patient characteristics and setting	Age: not reported Sex: not reported Ethnicity: not reported Country: South Korea Setting: extracted teeth Number of participants/teeth/sites: 100 teeth (5 were damaged so only 95 reported in results) Prevalence: enamel 0.80, dentine 0.15
Index tests	Category of test: QLF‐Digital Biluminator (QLF‐D, Inspektor Research Systems BV, Amsterdam, The Netherlands), using proprietary software (C3 v 1.16); "Pairs were formed with marginal ridges in contact to simulate the oral relationship" Sequence of test(s): visual then radiograph followed by QLF Examiner training and calibration: 1 calibrated dentist Teeth cleaning prior to examination: cleaned of all soft tissues Tooth drying prior to examination: dried with cotton wool Threshold applied: calculated within study, sound < ‐13.8, enamel ‐13.8 to ‐28.3, dentine > ‐28.3 Device specifics: shutter speed 1‐20 seconds, aperture 13.0, ISO speed 1600, 10 cm between specimen and the device
Target condition and reference standard(s)	Category: histology Sequence of index test and reference standard: index test then reference standard Training of examiner: not reported Blinding to index test: unclear Multiple tests: no Site selection: sectioned teeth Target condition: "enamel demineralization or a narrow surface zone of opacity", enamel or outer/inner dentine caries
Flow and timing	Participants with index test but no reference standard: 5 Participants with reference standard but no index test: 0 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?	No
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	Unclear
Could the selection of patients have introduced bias?		High risk
Are there concerns that the included patients and setting do not match the review question?			High
DOMAIN 2: Index Test (All)
Were the index test results interpreted without knowledge of the results of the reference standard?	Yes
If a threshold was used, was it pre‐specified?	No
If multiple tests were applied were different examiners used for each (in vivo)?	No
Could the conduct or interpretation of the index test have introduced bias?		High risk
Are there concerns that the index test, its conduct, or interpretation differ from the review question?			Low concern
DOMAIN 2: Index Test (Green fluorescence)
Were the index test results interpreted without knowledge of the results of the reference standard?	Yes
If a threshold was used, was it pre‐specified?	No
If multiple tests were applied were different examiners used for each (in vivo)?	No
Could the conduct or interpretation of the index test have introduced bias?		High risk
Are there concerns that the index test, its conduct, or interpretation differ from the review question?			Low concern
DOMAIN 2: Index Test (Blue fluorescence)
DOMAIN 2: Index Test (Red fluorescence)
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?	Unclear
Could the reference standard, its conduct, or its interpretation have introduced bias?		Low risk
Are there concerns that the target condition as defined by the reference standard does not match the question?			Low concern
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?	Yes
Were all patients included in the analysis?	No
Could the patient flow have introduced bias?		Low risk