Summary of survey scores (median of Likert score was subtracted)
Question	mean	Sum of positives (Ps)	Sum of negatives (Ns)	(Ps-Ns)/(Ps+Ns)	Count of positives (Pc)	Count of negatives (Nc)	(Pc-Nc)/(Pc+Nc)
1	-0.75	23.5	53.5	-0.39	13	27	-0.35
2	0.7	52.5	24.5	0.36	27	13	0.35
3	0.67	48.5	21.5	0.39	27	13	0.35
4	1.2	67	19	0.56	34	6	0.7
5	1.35	72	18	0.6	32	8	0.6
6	0.95	56	18	0.51	30	10	0.5
7	0.58	43.5	20.5	0.36	27	13	0.35
8	0.25	41.5	31.5	0.14	27	13	0.35
9	1.45	72.5	14.5	0.67	33	7	0.65
10	1.58	79	16	0.66	34	6	0.7
11	1.53	80	19	0.62	32	8	0.6
12	2.05	96	14	0.75	34	6	0.7
13	-0.83	22.5	55.5	-0.42	13	27	-0.35

Pearson correlations of survey scores (and p-values)
	mean	(Ps-Ns)/(Ps+Ns)	(Pc-Nc)/(Pc+Nc)
mean	1 (0)	0.981 (0)	0.959 (0)
(Ps-Ns)/(Ps+Ns)	0.981 (0)	1 (0)	0.981 (0)
(Pc-Nc)/(Pc+Nc)	0.959 (0)	0.981 (0)	1 (0)

Kendall tau rank correlations of survey scores (and p-values)
	mean	(Ps-Ns)/(Ps+Ns)	(Pc-Nc)/(Pc+Nc)
mean	1 (0)	0.916 (0)	0.816 (0)
(Ps-Ns)/(Ps+Ns)	0.916 (0)	1 (0)	0.821 (0)
(Pc-Nc)/(Pc+Nc)	0.816 (0)	0.821 (0)	1 (0)