Table 7.

Scoring System for Estimation of the Probability of Being Nonadherent to Once-Daily Prostaglandin Therapy

Step	Risk Score
1. Age (yrs)
≤50	16
>50	0
2. Race
White and other	0
Black	19
3. Self-reported general health
Excellent	0
Good	14
Poor or fair	17
4. Duration of glaucoma medication (yrs)
≤1	9
1–10	14
>10	0
5. Reported adherence over the past 1 month (%)
≤95	15
>95	0
6. Follow doctor’s orders exactly?
Strongly or somewhat agree	0
Neither/somewhat/strongly disagree	19
Sum of score, steps 1–6	0–100
7. Total score	Probability of being nonadherent (%)
0–10	3–5
11–20	6–10
21–30	11–17
31–40	18–27
41–50	28–41
51–60	42–57
61–70	50–70
71–80	71–82
81–90	83–89
91–100	90–94

To calculate the predicted probability for an individual patient, the scores for each predictor are calculated on steps 1–6 and then summed to give a total score, which is converted to a predicted probability of being nonadherent (step 7).