Repeatability and reproducibility of upper eyelid measurements

Aim-The aim of this study was to assess the repeatability and reproducibili ty by physicians of upper lid measurements and to investigate the influence of clinical experience on the learning curve effect. Methods-Both eyes of 22 outpatients were assessed for three basic measures of ptosis: marginal reflex distance (MRD) for upper and lower lids, upper l id skin crease (SC), and levator function (LF). Patients with variable eyel id positions were excluded. The patients were measured twice by a consultan t and once by each of a clinical fellow, a specialist registrar, and a seni or house officer in random order. Each observer was masked to their colleag ues' results and followed a standard measurement protocol. Data were analys ed using Bland-Altman plots. Results-Consultant repeatability was high and consistent, the median differ ence between measures being 0 for each of the four parameters. Clinically a cceptable reproducibility was shown in all measurements for even the least experienced physician and was particularly consistent for extreme observati ons. There was evidence of a learning curve effect. Conclusions-These results suggest that interobserver and intraobserver vari ability in assessment of upper lid ptosis using a standard measurement prot ocol is low and clinically acceptable when the technique of assessment is s tandardised.