Clinical Research Associates

D. Grading Criteria for Ease of Use & Image Quality

Ease of Use

The Ease of Use grade shown in the March 2001 CRA Newsletter is an average of the eight grades shown in the chart below.

This comparison study emphasizes the ability to capture all types of images (6 test photos) with minimal effort. Cameras that require changing the lens to take useful extraoral images are a clinical problem because the lens is not always conveniently located nearby, & dealing with the sheath & maintaining asepsis are problematic.

The grading criteria for each column are shown below the chart.

A. All component power switches are obvious and easy to use:

(Consider power switch(es) for camera only)

Obvious, easy switch = 7

• -1 Non-obvious switch (small, unlabeled, camouflaged)
• -2 Hidden switch
• -1 Each additional switch

B. Camera ready when Handpiece picked up:

(Evaluated after power has been turned on and patient file selected)

Camera and light ready when handpiece lifted from cradle, and turns off when replaced = 7

• -2 Each additional component that must be operated when picked up or sat down
• -3 If same control must be operated when picked up and sat down & requires reach

C. Sheath ease of use:

(1) Sheath slides on easily, (2) Slides off easily, (3) fits wells, (4) does not hamper controls, (5) does not slip
    around handpiece = 7

• -1 Any of the five criteria with a slight problem.
• -2 Any of the five criteria with a significant problem.
• -3 Any of the five criteria with a critical problem that makes camera use with sheath impossible.

D. Ease of Intraoral Access:

Evaluated while taking 6 test photos, with particular attention on distal and buccal of upper last molar.

Camera easily positioned for all photos = 7

• -1 if slight difficulty aligning or slight patient discomfort
• -1 for heavy or stiff cord
• -2 if significant difficulty aligning or patient discomfort
• -3 if a photo cannot be aligned correctly
• -4 If photo cannot be taken

E. Ease of focus and ability to achieve sharp focus:

(Evaluated for all photos within the camera's focal range)

All photos sharp focus with no effort required = 7

• -1 if manual focus adjustment required
• -1 if focus adjustment is difficult
• -1 if focus adjustment has large range of motion (>100 degrees)
• -1 if focus adjustment not labeled
• -1 if focus adjustment not provided but photos lack image quality

F. Simple, Fast, Easy Controls:

(Evaluation of commonly used controls except power switches and focus controls)

All controls are clearly labeled, obvious, simple, and easily operated = 7

• -1 Unlabeled control
• -1 Control is difficult to operate
• -1 Easy to cause accidental prints
• -1 Control required reaching to activate (i.e. printer)
• -1 Unstable capture
• -1 If footpedal is not stable
• -2 Complicated or easily misplaced controls (i.e. remotes)

G. Minimal Handpiece manipulation needed for 6 test photos:

All photos are acceptable and require no manipulation = 7

• -1 All photos acceptable, but require focusing
• -1 for each photo that lacks ability to resolve pathology
• -6 Camera cannot get all photos acceptable with a single lens

H. Portability:

Small modular unit with single simple connection = 7

• -1 Heavy or Large Size
• -1 Heavy or Large w/o handle
• -1 for each additional connection needed to be made
• -1 for connection which is not easy or requires alignment
• -6 for non-portable unit

Image Quality

The grade for Image Quality is an average of the 4 intraoral test photos (Lower Arch, Lower Lingual Anteriors, Distal of Last Molar, Buccal of Last Molar). A Grade for each of these photos is listed in the Image Quality Chart located on page 4 of the Newsletter and the average of these four grades is listed in Image Quality Chart on page 3. The Criteria for each test photo is listed below.

Monitor Image is Sharp and has Natural Color Grading Criteria:

(Evaluated for each of the 7 test photos, take best shot if 2 lenses available)

All photos are sharp, acceptable color, and pathology can be resolved = 7

• -1 Slight blur or pixelization
• -1 Slightly unnatural color
• -2 Significant blur or pixelization
• -2 Severely unnatural color
• -3 or more poor image quality reduces ability to resolve pathology
• -6 Non-useable image
• -1 Slight distortion
• -2 Severe distortion

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