Table 1. Combined Model Estimates From Models Fitted to Multiple Imputation Datasets.

Model/predictor	Coefficienta	Within Variance	Between Variance	95% CI	p
Model 1 (RQ1 and RQ4)
Correlations/ST, POWL, PONM, MREO
STb	0.45	0.58	0.02	[0.10, 2.08]	.30
POWL	1.07	<0.01	<0.01	[0.99, 1.15]	.11
PONM	0.95	<0.01	<0.01	[0.88, 1.02]	.16
ST X POWL (interaction)	0.89	<0.01	<0.01	[0.77, 1.03]	.11
ST X PONM (interaction)	0.88	<0.01	<0.01	[0.75, 1.03]	.11
POWL X PONM (interaction)	1.00	<0.01	<0.01	[0.99, 1.01]	.70
Model 2 (RQ3)
Predicting TTV
STb	18.94	65.62	1.43	[2.72, 35.16]	.02
POWL	1.34	0.22	0.02	[0.37, 2.30]	.01
PONM	-0.08	0.09	0.01	[-0.70, 0.54]	.80
ST X POWL (interaction)	0.62	0.88	0.03	[-1.27, 2.51]	.52
ST X PONM (interaction)	0.04	0.39	0.04	[-1.27, 1.35]	.95
POWL X PONM (interaction)	0.03	<0.01	<0.01	[-0.04, 0.11]	.38
Model 3 (RQ3)
Correlation/TTV, MREO
MREOc	24.27	76.21	4.08	[6.51, 42.03]	<.01
STb	27.48	83.84	4.89	[8.81, 46.16]	<.01
POWL	1.23	0.26	0.02	[0.17, 2.28]	.02
PONM	0.27	0.14	0.01	[-0.50, 1.04]	.49
MREO X ST (interaction)	41.90	299.59	5.50	[7.31, 76.49]	.02
MREO X POWL (interaction)	-0.71	0.67	0.08	[-2.43, 1.00]	.41
MREO X PONM (interaction)	0.20	0.37	0.08	[-1.13, 1.52]	.77
ST X POWL (interaction)	0.69	0.89	0.04	[-1.23, 2.60]	.48
ST X PONM (interaction)	0.60	0.44	0.06	[-0.81, 2.01]	.40
POWL X PONM (interaction)	0.03	<0.01	<0.01	[-0.06, 0.12]	.47
Model 4 (RQ4)
Correlation/workload change, MREO
MREOc	4.57	3.71	0.71	[0.39, 8.75]	.03
STb	2.10	3.98	0.42	[-2.07, 6.26]	.32
POWL	-0.32	0.01	<0.01	[-0.57, -0.07]	.01
PONM	0.17	0.01	<0.01	[-0.03, 0.37]	.09
MREO X ST (interaction)	8.65	14.29	1.73	[0.70, 16.60]	.03
MREO X POWL (interaction)	-0.28	0.03	0.01	[-0.71, 0.15]	.20
MREO X PONM (interaction)	0.07	0.02	0.01	[-0.28, 0.43]	.67
ST X POWL (interaction)	0.01	0.04	0.01	[-0.44, 0.46]	.97
ST X PONM (interaction)	0.18	0.02	0.01	[-0.19, 0.55]	.33
POWL X PONM (interaction)	0.01	<0.01	<0.01	[-0.02, 0.03]	.62

Note. CI = confidence interval; MRE = medication-related event; MREO = medication-related event occurrence;; PONM = pre-observation negative mood; POWL = pre-observation workload; RQ = research question; ST = shift type; TTV = total task volume;

^aregression coefficients are reported for Model 1, 2, and 4. Adjusted odds ratios are reported for Model 3.

^bST was effect coded, in which the reference level was the mean of day shift and night shift and the weights were -0.5 and 0.5.

^cMREO was effect coded, in which the reference level was the mean of absence of MRE and presence of MRE(s) and the weights were -0.5 and 0.5.