Table 3.

Days of EMA responding and total number of surveys completed, ordinal logistic and negative binomial regression models with robust standard errors (N = 168)^a

	Days of EMA responding (quintiles)				Total number of surveys completedb
	aOR	95% Conf. Int.		p-value	aIRR	95% Conf. Int.		p-value
Step 1 variables:c
Female vs. male	4.06	2.05	8.05	<0.001	1.51	1.25	1.82	<0.001
Age	1.02	0.94	1.10	0.677	1.01	0.99	1.04	0.373
Race/ethnicity (Ref = NH white)
NH Black	3.09	0.61	15.63	0.172	1.04	0.72	1.51	0.823
Hispanic	0.62	0.31	1.23	0.169	0.86	0.66	1.11	0.252
Other (NH)	3.07	1.49	6.33	0.002	1.36	1.07	1.73	0.013
Wald test	chi2(3) = 15.89, p=0.001				chi2(3) = 9.84, p=0.02
Condition (Ref = Condition 1)d
Condition 2	0.71	0.37	1.34	0.285	1.04	0.84	1.30	0.705
Condition 3	0.71	0.35	1.43	0.333	1.12	0.86	1.45	0.395
Wald test	chi2(2) = 1.62, p=0.44				chi2(2) = 0.74, p=0.69
Step 2 variables: e
Education (Ref = less than high school)
High school	0.71	0.33	1.51	0.369	0.99	0.75	1.31	0.969
Post-secondary	1.05	0.49	2.23	0.905	1.04	0.80	1.36	0.758
Wald test	chi2(2) = 1.58, p=0.45				chi2(2) = 0.20, p=0.91
Employed vs. not employed	0.90	0.49	1.66	0.738	1.01	0.82	1.25	0.941
Jail past 6 months	0.53	0.27	1.04	0.065	0.89	0.67	1.18	0.400
Homeless (Ref = Not homeless)
Thought of as homeless	0.60	0.28	1.29	0.192	0.80	0.63	1.02	0.074
Slept in non-dwelling > 7 nights	0.40	0.22	0.74	0.003	0.66	0.53	0.83	< 0.001
Wald test	chi2(2) = 8.82, p=0.012				chi2(2) = 13.74, p=0.001
Currently in drug treatment	2.64	1.05	6.62	0.039	1.33	1.02	1.72	0.032
Frequency of injection (Ref = less than 4 days per week)
4 to 6 days per week	1.10	0.36	3.38	0.874	0.93	0.61	1.42	0.750
daily, 2–4 times per day	1.24	0.43	3.55	0.692	1.03	0.74	1.44	0.855
daily, 5 or more times per..	1.30	0.45	3.73	0.626	0.97	0.69	1.38	0.881
Wald test	chi2(3) = 0.37, p=0.95				chi2(3) = 0.47, p=0.93
Injected with used syringe past 6 months (Ref = Never)
Rarely	0.60	0.29	1.24	0.169	0.84	0.65	1.08	0.173
Sometimes	0.34	0.17	0.70	0.003	0.66	0.50	0.86	0.002
Wald test	chi2(2) = 8.63, p=0.013				chi2(2) = 9.85, p=0.007
BPDf Screener core	1.03	0.91	1.16	0.646	1.01	0.97	1.05	0.704
Difficulties in Emotion Regulation Scale	1.01	1.00	1.02	0.085	1.00	1.00	1.01	0.155
Impulsivity: (Lack of) Premeditation and Perseverence	0.72	0.42	1.25	0.239	0.96	0.80	1.15	0.625
Impulsivity: Positive Urgency	0.86	0.58	1.25	0.421	1.01	0.88	1.16	0.925
Impulsivity: Negative Urgency	0.71	0.42	1.21	0.213	0.95	0.80	1.12	0.543
Trait negative affect	1.51	0.98	2.33	0.065	1.09	0.94	1.26	0.254
Depression (Ref = no symptoms)
Mild depression	1.06	0.41	2.76	0.902	0.97	0.64	1.47	0.885
Moderate to severe depression	1.83	0.78	4.27	0.165	1.12	0.77	1.64	0.547
Wald test	chi2(2) = 3.63, p=0.16				chi2(2) = 1.62, p=0.44

^a2 observations missing on covariates

^bModel includes offset to adjust for number of surveys available based on condition enrollment

^cEntered all at once

^dConditions: 1 = 6 assessments per day at $1.50 ea., 2 = 5 per day at $1.80 ea., 3 = 4 per day at $2.25 ea.

^eEntered separately, adjusted for selected step 1 variables

^fBorderline personality disorder