Vertical off-centring below the gantry isocentre is the most frequently reported CT positioning error among radiographers¶
Claim · All claims
Evidence · 1 study · associationalr2·q2
Currency · newest study 2026 · not yet checked against its sources · not reviewed by a person · recheck by 2031: baselines and conditions change
Subclaims¶
Reading the evidence codes
q is the design tier, i the impact, n the sample, and the kind with its r
the rigour judged within that kind: what each code means.
This claim: no standardized effect is recorded in observations/ for it yet, so no benchmark reading is possible.
q2 i? In an international survey, vertical off-centring (y-axis) below the gantry isocentre was the most frequently reported positioning error (31.5%), ahead of lateral off-centring (23.4%) and vertical off-centring above the isocentre (16.5%). → Hadi Yasser H. 2026
Evidence¶
Hadi Yasser H. 2026¶
Hadi Yasser H., Bani‐Ahmad Mo'men, Moore Niamh, Clark Kevin R., Al‐Hayek Yazan, Albeshan Salman M., Alghamdi Sultan B., Precht Helle, England Andrew, McEntee Mark. (2026). Patient Centring in CT: An International Survey of Clinical Practice and Future Directions. Journal of Medical Radiation Sciences. https://doi.org/10.1002/jmrs.70119
q2 · i? · associational · r2
Self-report survey of 321 CT radiographers in 43 countries using a 38-question instrument; the article notes these are "based on self‐reported perceptions rather than measured positioning data," with 31.5% reporting vertical off-centring below the isocentre.
"Vertical off‐centring (y‐axis) below the gantry isocentre was most frequently reported (101, 31.5%), followed by lateral off‐centring (x‐axis) (75, 23.4%) and vertical off‐centring above the isocentre (53, 16.5%)."
Discussion¶
Related Claims¶
- Routine post-acquisition verification of HU values is uncommon and knowledge of positioning effects on CT numbers is inconsistent — related
- Access to and consistent use of automated centring technology remain limited among CT radiographers — related
- Radiographers show substantial uncertainty about how localiser radiograph direction affects radiation dose and ATCM behaviour — related
- Mean CT centring knowledge score indicates only moderate proficiency, with greater score variability among less experienced and lower-volume radiographers — related
- CT-specific qualification, experience and workload were not significantly associated with high CT centring knowledge scores in the international sample — related
Page metadata
| Field | Value |
|---|---|
type |
claim |
id |
vertical-below-isocentre-most-reported-ct-centring-error |
title |
Vertical off-centring below the gantry isocentre is the most frequently reported CT positioning error among radiographers |
description |
Vertical off-centring below the gantry isocentre is the most frequently reported CT positioning error among radiographers |
status |
review |
evidence_strength |
moderate |
newest_evidence |
2026 |
recheck_by |
2031 |
generated |
by process:wiki-ingest on 2026-09-26 |
trust |
unverified — no one has confirmed this page's content |
sources |
1 — hadi-yasser-h-2026 |
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