A comparison of estimators from self-controlled case series, case-crossover design, and sequence symmetry analysis for pharmacoepidemiological studies

Table 8 Results of Simulations to Evaluate the Influence of Misspecified Risk Periods

	Settings	Results of simulations
Methods (Effect measures)	Days of risk	Mean of estimates (Ratio scale)	Bias (Log scale)	Empirical standard error	Mean squared error	Mean standard error	Coverage (%)
SCCS (IRR)	5	2.89	−0.0377	0.1729	0.0313	0.1661	95.0
CCO (OR)		0.99	−1.1068	0.2420	1.2835	0.2406	0.5
SSA (ASR)		3.14	0.0466	0.4511	0.2056	0.4076	94.6
SCCS (IRR)	25	2.19	−0.3134	0.0907	0.1065	0.0878	4.4
CCO (OR)		2.21	−0.3056	0.1616	0.1195	0.1605	50.3
SSA (ASR)		2.23	−0.2981	0.1891	0.1246	0.1829	60.2

Abbreviations ASR Adjusted sequence ratio, CCO Case-crossover, IRR Incident rate ratio, OR Odds ratio, SCCS Self-controlled case series, SSA Sequence symmetry analysis

ISSN: 1471-2288