Maeda 1994.

Study characteristics
Patient Sampling	Single‐centre, case‐control study. Videokeratographs were drawn from the Louisiana State University Eye Center patient population and were divided randomly by category into 2 sets. Each set comprised 8 categories: normal, keratoconus, keratoplasty, epikeratophakia, excimer laser photorefractive keratectomy, radial keratotomy, contact lens‐induced warpage, and other.
Patient characteristics and setting	The study included the following categories of participants. Healthy controls People with keratoconus People who underwent refractive surgery or who had undergone a keratoplasty The study did not include people seeking refractive surgery.
Index tests	Combined discriminant analysis and classification tree analysing images from the TMS‐1. The keratoconus detection programme was developed using a training set of 100 corneas and evaluated with a validation set of an additional 100 corneas. Maps were first classified as either keratoconus, borderline, or non‐keratoconus. The borderline maps were then divided into keratoconus or non‐keratoconus by certain indices. Next, all keratoconus patterns were classified into either peripheral or central keratoconus using a threshold combination of these indices. Final output of the system was the display of the certainty of keratoconus.
Target condition and reference standard(s)	The included cases were diagnosed by 3 corneal topography researchers based on clinical records and topography. All images were made by a TMS‐1. The diagnosis was made before the algorithm analysed the images.
Flow and timing	All participants received the index and reference test. All data were included in a 2 × 2 table.
Comparative	Not applicable
Notes	Supported in part by National Institutes of Health grants EY03311 and EYO2377 and by Computed Anatomy, Inc. and Menicon, Co., Ltd.
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?	No
Did the study avoid inappropriate exclusions?	No
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 tests)
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?	Unclear
Was the model designed in an appropriate manner?	Yes
Could the conduct or interpretation of the index test have introduced bias?		Low 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 standard likely to correctly classify the target condition?	Yes
Were the reference standard results interpreted without knowledge of the results of the index tests?	Yes
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?			Unclear
DOMAIN 4: Flow and timing
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
DOMAIN 5: Comparative