A peer-reviewed study of 116 healthy participants linked the steadiness of circular finger movements on a smartphone with hand preference. With eight seconds of movement data, agreement with the handedness questionnaire reached 94 per cent. The dominant finger varied less between turns. Only nine participants were left-handed, and the writing hand was always tested first.
A single peer-reviewed study connected hand preference with the consistency of finger circles traced on a smartphone. Atsushi Takagi and colleagues compared movements from 116 healthy, relatively young participants. Successive turns were more consistent when traced with the dominant index finger. Using eight seconds of data, classification matched the handedness questionnaire for 94 per cent of participants.[1]
Participants drew circles roughly 1.5 centimetres across at about three turns per second. A modified Hausdorff distance, a measure of shape similarity, compared neighboring revolutions and reduced the influence of fixed touch-position offsets. Mean frequencies were 3.2 hertz for the dominant finger and 2.9 hertz for its counterpart. Accounting for speed differences did not remove the association with hand preference.[1]
The Edinburgh Handedness Inventory, a self-report measure of preferred hand, placed 107 people in the right-handed group and nine in the left-handed group. Its scores clustered at the extremes, while differences between the two fingers’ variability were approximately normally distributed. The writing hand was always tested first, linking preference with trial order. The experiment did not include children or older adults, nor participants from patient groups.[1]
The small left-handed group makes its classification estimate imprecise. Each hand also traced in only one direction. The study therefore assessed one movement protocol against a questionnaire, without establishing a diagnostic test across different ages or movement disorders.[1]
