Fig. 4: Agreement between measurements of horizontal deviation made using the standard alternate prism cover test (APCT), performed by an orthoptist, and the novel STARE method.

A Bland–Altman plot showing mean agreement (black line), and 95% limits of agreement (red lines), both with ±95% confidence intervals. Note that the top right point was not included when computing the limits of agreement shown, but statistics with and without this point included are given in the main text. B Scatter plot, including unity line and Pearson correlation statistics.