Table 2.

Cross-Method Agreement of Pill Count and Medication Diaries with Electronic Monitoring Adherence

											Adherence agreement
			EM Nonadherence		Other method Nonadherence		EM Adherence		Other method Adherence		Kappa coefficient				Spearman correlation
EM	Other method	Total N	n	%	n	%	n	%	n	%	n	%	Kappa	p Valuea	n	rs	p Valueb
EM	Pill count	31	7	22.58	4	12.90	24	77.42	27	87.10	23	74.19c	0.46c	0.05	29	0.67c	0.0003
EM	Parent's diary	31	7	22.58	5	16.13	24	77.42	26	83.87	22	70.97d	0.38d	0.09	26	0.36d	0.09
EM	Patient's diary	31	7	22.58	9	29.03	24	77.42	22	70.97	18	58.06e	0.16e	0.64	22	0.30e	0.16

p Values were adjusted using the false discovery rate (Benjamini and Hochberg, 1995). Nonadherence was operationalized as <80% adherence (across the average of the 12-week trial). Spearman rho was assessed between continuously measured 12-week mean EM adherence and each of the other methods of continuously measured 12-week mean adherence (pill counts and medication diaries). n = number of participants who were adherent or nonadherent by method of adherence or cross-method comparison of adherence agreement, vis-à-vis the operationalization (or measurement) of adherence (binomial or continuous).

^aExact two-sided.

^bTwo-tailed test.

^cAdherence agreement between pill count and EM.

^dAdherence agreement between parent's diary and EM.

^eAdherence agreement between patient's diary and EM.