Use mixed effects methods to compare the mean change in TBUT immediately post-instillation against baseline according to participant (1, 2, . . . , 14) and nonblink time period (3 sec vs. 6 sec vs. 10 sec). For this analysis, average the first and second replicates and right and left eyes for each participant. Thus, each participant is represented by an average of four values. Represent the participant effect as a random effect and the non blank time-period effect as a fixed effect represented by a set of 2 dummy variables. If there are overall significant differences for the non blink time period, then identify which non blink time periods are significantly different?