Table 2.

Practitioners' awareness and knowledge towards radiation protection according to their educational level.

No.	Knowledge items	Response	Educational level				P-value
			Undergraduate students (%)	Endodontic postgraduate students (%)	General practitioners (%)	Endodontists (%)
1	Are you familiar with ALARA principle?	Yes	74.8a	75a	48.7b	72.5a	0.001 ∗
		No	25.2	25	51.3	27.5
2	Are you familiar with the recommendations of the NCRP and ICRP?	Yes	29.6	38.2	28.9	43.5	0.16
		No	70.4	61.8	71.1	56.5
3	Are you aware of the radiation hazard symbol?	Yes	80.9	83.8	82.9	92.8	0.179
		No	19.1	16.2	17.1	7.2
4	Does digital radiography require less exposure than conventional?	Yes	72.2a	85.3b	75a	94.2b	0.014 ∗
		No	14.8	8.8	11.8	2.9
		I do not know	13	5.9	13.2	2.9
5	Do high-speed films reduce exposure?	Yes	65.2a	77.9b	69.7a	88.4b	0.002 ∗
		No	9.6	8.8	2.6	7.2
		I do not know	25.2	13.2	27.6	4.3
6	Specify the importance of the use of collimators and filters in dental radiography.	Very important + important	85.2	94.1	81.6	95.7	0.144
		Moderately important	8.7	2.9	10.5	4.3
		Of little importance + unimportant	6	2.9	7.9	0
7	What is the ideal distance of operator “Position Distance Rule” when exposed to dental radiography?	4ft., 90 o -135 o	7.8	1.5	5.3	1.4	0.084
		4ft, 60 o -90 o	9.6	4.4	10.5	5.8
		6ft, 90 o -135 o	67	86.8	64.5	76.8
		6ft, 60 o -90 o	15.7	7.4	19.7	15.9

^∗Significant at P < 0.05. The same superscript letters indicate no significant differences (P > 0.05).