Validity of the Medication Adherence Rating Scale for Adherence to Inhaled Corticosteroids among Older Adults with Asthma or Chronic Obstructive Pulmonary Disease

Figures & data

Table 1. Demographic and clinical characteristics of patients with asthma.

		Underwent objective adherence monitoring
Characteristic	All patients (n = 341) N (%)	Yes (n = 244) n (%)	No (n = 97) n (%)	P
Age				.52
60–64 years	148 (44)	105 (43)	43 (45)
65–69 years	85 (25)	58 (24)	27 (28)
≥70 years	106 (31)	80 (33)	26 (27)
Male	52 (15)	39 (16)	13 (14)	.57
Race/ethnicity				.56
White, non-Hispanic	74 (22)	57 (23)	17 (18)
Black, non-Hispanic	104 (31)	73 (30)	31 (32)
Hispanic	132 (32)	91 (37)	41 (43)
Other	30 (9)	23 (9)	7 (7)
Limited English-speaking ability	86 (25)	59 (24)	27 (28)	.45
Education level				.21
Some high school or less	113 (33)	64 (32)	49 (38)
High school graduate	61 (18)	40 (16)	21 (22)
Some college	70 (21)	51 (21)	19 (20)
College graduate	96 (28)	76 (31)	20 (21)
General health				.81
Very good to excellent	78 (23)	58 (24)	20 (21)
Good	105 (31)	74 (30)	31 (32)
Fair to poor	157 (46)	111 (46)	46 (47)
Monthly household income <$1350	179 (54)	125 (53)	54 (57)	.49
Asthma history
≥1 ER visit past year	86 (37)	63 (37)	23 (35)	.78
≥1 Hospital visit past year	37 (27)	30 (29)	7 (21)	.38
Oral steroid use past year	336 (99)	241 (72)	95 (28)	.00
ACQ score	131 (38)	95 (39)	36 (37)	.75

ER denotes emergency room; ACQ, asthma control questionnaire.

Table 2. Demographic and clinical characteristics of patients with chronic obstructive pulmonary disease.

		Underwent objective adherence monitoring
Characteristic	All patients (n = 342) N (%)	Yes (n = 189) n (%)	No (n = 153) n (%)	P
Age				.14
55–59	56 (16)	31 (16)	25 (16)
60–64	74 (22)	40 (21)	34 (22)
65–69	77 (23)	51 (27)	26 (17)
≥70	135 (40)	67 (35)	68 (44)
Male	64 (42)	81 (43)	145 (42)	.84
Race/ethnicity				.69
White, non-Hispanic	123 (36)	66 (35)	57 (37)
Black, non-Hispanic	155 (45)	87 (46)	68 (44)
Hispanic	54 (16)	32 (17)	22 (14)
Other	10 (3)	4 (2)	6 (4)
Limited English-speaking ability	33 (10)	19 (10)	14 (9)	.78
Education level				.22
Some high school or less	90 (26)	45 (24)	35 (30)
High school graduate	77 (23)	48 (25)	29 (19)
Some college	79 (23)	48 (25)	31 (20)
College graduate	95 (28)	48 (25)	47 (31)
Monthly household income <$1,350	159 (47)	89 (48)	70 (47)	.87
General health				.61
Very good to excellent	66 (19)	39 (21)	27 (18)
Good	118 (35)	67 (35)	51 (33)
Fair to poor	158 (46)	83 (44)	75 (49)
COPD history
≥1 ER visit past year	96 (39)	53 (42)	43 (36)	.36
≥1 Hospital visit past year	84 (60)	52 (68)	32 (51)	.04
Oral steroid use past year	124 (36)	77 (41)	47 (31)	.05
COPD severity score ≥15	47 (14)	27 (14)	20 (13)	.74

COPD denotes chronic obstructive pulmonary disease; ER, emergency room.

Table 3. Mean Medication Adherence Report Scale Scores, by adherence as determined by objective measures.

Cohort	Adherent to medication by objective monitoring
	Yes	No	P
Asthma, MARS score, mean (sd)	4.15 (0.70)	3.87 (0.80)	.005
COPD, MARS score, mean (sd)	4.13 (0.70)	4.09 (0.72)	.63

COPD denotes chronic obstructive pulmonary disease; MARS, Medication Adherence Report Scale.

Table 4. Sensitivity and Specificity of the Medication Adherence Report Scale at different threshold values among patients with asthma.

MARS	Frequency	Sensitivity	95 % CI	Specificity	95 % CI
≥5	26	0.29	0.20–0.38	0.91	0.86–0.95
≥4.5	54	0.60	0.50–0.70	0.71	0.64–0.78
≥4	71	0.79	0.70–0.87	0.47	0.39–0.55
≥3.5	80	0.89	0.82–0.95	0.21	0.15–0.28
≥3.0	87	0.97	0.93–1.00	0.08	0.04–0.12

Table 5. Sensitivity and Specificity of the Medication Adherence Report Scale at different threshold values among patients with COPD.

MARS	Frequency	Sensitivity	95 % CI	Specificity	95 % CI
≥5	16	0.23	0.13-0.33	0.96	0.87-0.97
≥4.5	36	0.51	0.40-0.63	0.68	0.60-0.76
≥4	51	0.73	0.62-0.83	0.42	0.33-0.51
≥3.5	56	0.80	0.71-0.89	0.20	0.13-0.27
≥3.0	64	0.91	0.85-0.98	0.03	0.00-0.06

COPD denotes chronic obstructive pulmonary disease; MARS, Medication Adherence Report Scale.

Figure 1. Receiver operating characteristic curve (AUC= 0.687) evaluating the accuracy of the MARS compared with objective monitoring in the asthma cohort. Abbreviations: AUC, area under the curve; MARS, Medication Adherence Report Scale.

Figure 2. Receiver operating characteristic curve (AUC= 0.612) evaluating the accuracy of the MARS compared with objective monitoring in the COPD cohort. Abbreviations: AUC, area under the curve; MARS, Medication Adherence Report Scale; COPD, C