Can visual analogue scale be used in radiologic subjective image quality assessment?

• Published in: Pediatric radiology Vol. 48; no. 11; pp. 1567 - 1575
• Main Authors: Suther, Kathrine Rydén, Hopp, Einar, Smevik, Bjarne, Fiane, Arnt Eltvedt, Lindberg, Harald Lauritz, Larsen, Stig, de Lange, Charlotte
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-10-2018; Springer Nature B.V; Springer Verlag
• Subjects: Adolescent; Adolescents; Angiography; Arteries; Case-Control Studies; Child; Coronary artery; Coronary vessels; Female; Humans; Image Interpretation, Computer-Assisted; Image quality; Imaging; Magnetic Resonance Angiography - standards; Magnetic resonance imaging; Male; Medical imaging; Medicine; Medicine & Public Health; Neuroradiology; Nuclear Medicine; Oncology; Original; Original Article; Pediatrics; Precession; Quality; Quality assessment; Quality control; Quality of Health Care; Radiology; Reproducibility; Resonance; Statistical analysis; Steady state; Teenagers; Transposition; Transposition of Great Vessels - diagnostic imaging; Transposition of Great Vessels - surgery; Ultrasound; Veins & arteries; Visual Analog Scale; Fixed point scale; Heart; Image quality; Magnetic resonance imaging; Visual analogue scale; Coronary artery; Adolescents
• ISSN: 0301-0449; 1432-1998
• DOI: 10.1007/s00247-018-4187-8

Background
Assessment of qualitative or subjective image quality in radiology is traditionally performed using a fixed-point scale even though reproducibility has proved challenging.
Objective
Image quality of 3-T coronary magnetic resonance (MR) angiography was evaluated using three scoring methods, hypothesizing that a continuous scoring scale like visual analogue scale would improve the assessment.
Materials and methods
Adolescents corrected for transposition of the great arteries with arterial switch operation, ages 9–15 years
(n
=12), and healthy, age-matched controls (
n
=12), were examined with 3-D steady-state free precession magnetic resonance imaging. Image quality of the coronary artery origin was evaluated by using a fixed-point scale (1–4), visual analogue scale of 10 cm and a visual analogue scale with reference points (figurative visual analogue scale). Satisfactory image quality was set to a fixed-point scale 3=visual analogue scale/figurative visual analogue scale 6.6 cm. Statistical analysis was performed using Cohen kappa coefficient and agreement index.
Results
The mean interobserver scores for the fixed-point scale, visual analogue scale and figurative visual analogue scale were, respectively, in the left main stem 2.8, 5.7, 7.0; left anterior descending artery 2.8, 4.7, 6.6; circumflex artery 2.5, 4.5, 6.2, and right coronary artery 3.2, 6.3, 7.7. Scoring with a fixed-point scale gave an intraobserver κ of 0.52–0.77 while interobserver κ was lacking. For visual analogue scale and figurative visual analogue scale, intraobserver agreement indices were, respectively, 0.08–0.58 and 0.43–0.71 and interobserver agreement indices were up to 0.5 and 0.65, respectively.
Conclusion
Qualitative image quality evaluation with coronary 3-D steady-state free precession MR angiography, using a visual analogue scale with reference points, had better reproducibility compared to a fixed-point scale and visual analogue scale. Image quality, being a continuum, may be better determined by this method.