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[Christmas article: Diagnostic Investigation of Numerical Gauging in Length Estimation - Determining Once and for all
Frederik Damsgaard Højsager1, Astrid Næraa Høeg Vendelsøe2, Katia Damsgaard Højsager3
1Ortopædkirurgisk Afdeling, Sygehus Lillebælt, Kolding.
Introduction:
Accurate visual estimation of length is a skill often relied upon in clinical practice, yet little is known about surgeons' ability to judge distances without measurement tools. This multicenter study aimed to evaluate physicians' ability to visually estimate a length of 13.1 cm and to explore potential differences between surgical specialities.
Method:
A total of 105 physicians from several Danish hospitals participated. Each was asked to estimate a 13.1 cm distance by eye without using any measuring device. Participants' specialities and shoe size were recorded for subgroup analysis.
Results:
Across all participants, the mean estimated length was 12.0 cm, indicating a general underestimation. Orthopaedic surgeons estimated significantly shorter lengths (mean 11.5 cm) compared to urologists (mean 12.5 cm; p less-than 0.05). Shoe size showed no correlation with estimation accuracy.
Conclusion:
Physicians tend to underestimate 13.1 cm when judging by eye. Urologists, however, demonstrated the most accurate estimates, possibly reflecting their daily clinical calibration to relevant anatomical measures. Orthopaedic surgeons' shorter estimates may reflect a more modest internal reference. The findings highlight the variability of clinical »eyeballing« - even when the length in question is familiar.
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