Table IV.

Percent difference/DTA comparison between EPID converted dose planes to 2D diode array measurements for seven designed test fields (Varian linac) and two analysis criteria (% difference/DTA): 3%/3mm and 2%/2mm (DTA). The number of distinct diode measurement positions in the fields is shown, as some of these fields were quite small and did not cover many diodes in the MapCHECK array.

Field Description	3mm/3% pass rate	2mm/2% pass rate	Points Analyzed
1.0 × 1.0 MLC, 10 × 10 Primary Jaws	100.0	100.0	6
1.5 × 2.0 MLC, 10 × 10 Primary Jaws	100.0	91.7	12
2.0 × 1.0 MLC, 10 × 10 Primary Jaws	100.0	93.3	15
3.0 × 3.0 MLC, 10 × 10 Primary Jaws	100.0	100.0	28
5.0 × 5.0 MLC, 10 × 10 Primary Jaws	97.1	91.3	69
7.0 × 7.0 MLC, 10 × 10 Primary Jaws	94.2	88.3	121
Inverted Dose Pyramid (11 MLC segments, fixed 10×10 Primary Jaws)	99.2	88.4	250