Table 2.

Predictive accuracy of differing patterns of dose timing and mistiming on whether subjects achieve ‘optimal’ adherence (≥95 % of prescribed doses taken)

Grouping variables	<95 % of doses taken
	AROC curvea	95 % CI
Dose timing patterns
Early dose taking, yes/nob	0.53	0.50–0.56
Late dose taking, yes/nob	0.56	0.41–0.71
Symmetrical dose taking, yes/nob	0.58	0.44–0.73
Dose mistiming patterns
Early mistimed dose pattern, yes/noc	0.53	0.41–0.65
Late mistimed dose pattern, yes/noc	0.61	0.43–0.80
Symmetrical mistiming, yes/noc	0.64	0.46–0.82
Continuous variables
Proportion of all doses taken earlyd	0.74	0.59–0.88
Proportion of all doses taken lated	0.74	0.59–0.89
Proportion of mistimed doses taken earlyd	0.65	0.48–0.82
Proportion of mistimed doses taken lated	0.65	0.48–0.82
Slope of regression line for dose events over calendar timee	0.51	0.26–0.75
RMSE of regression linef	0.79	0.62–0.97

AROC curve area under the receiver operating characteristic curve, RMSE residual mean standard error

^aThe AROC statistic indicates how well the predictor variable classifies the outcome (optimal adherence). An AROC of 0.5 provides no discriminant information; an AROC of 1.0 connotes a perfect (errorless) test

^bDefined as >60 % of doses (regardless of whether within the 1 h compliance window) falling early or late, or, in the case of the symmetric pattern, meeting neither of these definitions

^cDefined as >60 % of mistimed doses taken early or late, or in the case of a symmetrical mistiming pattern, meeting neither of these definitions

^dSimilar analysis to those described in items 2 and 3 above, except defining variables are now continuous instead of dichotomous

^eThis is the slope of the dose taking events over calendar time, i.e., whether the individual’s behavior is stable (zero slope) or shifting with time (positive or negative slope)

^fThe residual mean standard error measures the extent of dose time variability from the regression line for each scatter plot. Individuals whose doses all fall very close to the regression line (few doses early or late) have lower RMSE; those with a high degree of scatter (many doses taken early or late), have larger RMSE