Sources of variance in ocular microtremor.
This study presents a preliminary investigation of the sources of variance in the measurement of ocular microtremor frequency in a normal population. When the results from both experienced and relatively inexperienced operators are pooled, factors that contribute significantly to the total variance include the measurement procedure (p < 0.001), day-to-day variations within subjects (p < 0.001), and inter-subject differences (p < 0.01). Operator experience plays a role in determining the measurement precision: the intra-subject coefficient of variation is about 5% for a very experienced operator, and about 14% for a relatively inexperienced operator.
Sheahan
N F
NF
Mercer's Institute for Research in Ageing, St James's Hospital, Dublin, Ireland.
Coakley
D
D
Bolger
C
C
O'Neill
D
D
Fry
G
G
Phillips
J
J
Malone
J F
JF
D000328:Adult; D000704:Analysis of Variance; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D014202:Tremor / Q000453:epidemiology*