Table 8. Optimal margins for PTV considering both inter- and intra-fractional variations.

Recipe	Margins considering intra-fractional variations only			Margins considering both inter- and intra-fractional variations
	RL (mm)	SI (mm)	AP (mm)	RL (mm)	SI (mm)	AP (mm)
2∑ + 0.7σ [13]	2.87	3.66	3.99	3.04	3.75	4.19
2∑ + 0.7σ [14]	3.5	4.41	4.88	3.7	4.52	5.12

Abbreviations: RL, right-left; SI, superior-inferior; AP, anterior-posterior; ∑, standard deviation of systematic errors; σ, standard deviation of random errors