Feng 2005.

Study characteristics
Patient Sampling	Method of sampling: unclear Included conditions: non‐cavitated Teeth: unclear Sealants: no Surface: occlusal
Patient characteristics and setting	Age: 12 to 13 years Sex: 169 male, 131 female Ethnicity: not reported Country: China Setting: school based Number of participants/teeth/sites: 1732 teeth/300 participants Prevalence: 0.21 enamel
Index tests	Category of test: QLF Inspektor Research System BV, Amsterdam, Netherlands Sequence of test(s): visual then QLF and digital photo Examiner training and calibration: not reported Teeth cleaning prior to examination: professionally cleaned Tooth drying prior to examination: yes, with high pressure air (triple syringe) for 30 seconds Threshold applied: "for QLF photos, upper anterior teeth that had decreased fluorescence in the cervical area were diagnosed as demineralization" Device specifics: none reported
Target condition and reference standard(s)	Category: visual, also digital photographs Sequence of index test and reference standard: unclear Training of examiner: not reported Blinding to index test: unclear Multiple tests: no Site selection: unclear Target condition: white spot lesions
Flow and timing	Participants with index test but no reference standard: 0 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	Translation completed by a Cochrane author, data extracted with visual as reference standard
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	Unclear
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)
Were the index test results interpreted without knowledge of the results of the reference standard?	No
If a threshold was used, was it pre‐specified?	Unclear
If multiple tests were applied were different examiners used for each (in vivo)?
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 2: Index Test (Green fluorescence)
Were the index test results interpreted without knowledge of the results of the reference standard?	No
If a threshold was used, was it pre‐specified?	Unclear
If multiple tests were applied were different examiners used for each (in vivo)?
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 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?	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?			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?	Yes
Could the patient flow have introduced bias?		Low risk