Table 4.

Statistical analysis (U-Test, p = 0.05 with Bonferroni correction, p = 0.0125) of test series with respect to remaining chitosan coating on PET.

3,000 cycles of abrasion
Test series	U	p	Bonferroni-corrected significance
I versus II	23.0	0.04516	–
II versus III	49.5	1.00000	–
II versus IV	36.0	0.30749	–
IV versus V	37.0	0.34471	–
IV versus VI	39.0	0.42736	–
IV versus VII	36.0	0.30749	–
V versus VII	43.0	0.62318	–
VI versus VII	28.0	0.10411	–
VI versus III	45.0	0.73373	–
30,000 cycles of abrasion
Test series	U	p	Bonferroni-corrected significance
I versus II	2.0	0.00033	*
II versus III	36.0	0.30749	–
II versus IV	47.0	0.85011	–
IV versus V	14.0	0.00729	*
IV versus VI	36.5	0.32575	–
IV versus VII	45.0	0.73373	–
V versus VII	19.5	0.02334	–
VI versus VII	32.0	0.18588	–
VI versus III	46.5	0.82060	–

* statistically significant with Bonferroni correction.