Table 4.

Percentage of children (4–12 years), youth (13–21 years) and adults (22–54 years)with Rett syndrome who show functions and forms of communicative behaviors, chi-square and p-values

Function/form	Children (n = 41) %	Youth (n = 30) %	Adults (n = 50) %	χ2 (df = 1)	p
Social convention
Eye contact/gaze	98	93	92	–a	.61
Laughing/smiling	78	87	84	1.01	.61
Approaching person	17	10	8	–a	.39
Distancing from person	15	10	8	–a	.57
Attention to self
Touch person	63	50	32	9.06	.01*
Approaching person	32	17	8	8.57	.01*
Reject/protest
Eye contact/gaze	32	43	6	16.38	.01*
Resisting	22	37	16	4.55	.10
Grumbling	24	30	2	13.43	.01*
Temper tantrum	10	7	12	–a	.87
Request an object
Eye contact/gaze	76	63	36	15.18	.00**
Reaching	37	0	10	19.44	.00**
Taking object	24	17	4	7.98	.02*
Approaching person	29	7	4	14.03	.00**
Request action
Vocalization	37	37	6	15.10	.00*
Words/speech	12	13	4	–a	.22
Request information
Eye contact/gaze	7	27	2	–a	.00**
Tocuh person	2	7	0	–a	.11
Commenting
Looking away	20	40	28	3.60	.17
Whining	37	17	14	7.36	.03*
Eyes closing	7	10	22	4.65	.10
Hitting	12	13	6	–a	.50
Choice making
Eye contact/gaze	63	47	28	11.50	.00**
Approaching person	24	10	4	8.84	.01*
Reaching	22	7	2	–a	.01*
Distancing from person	17	7	4	–a	.11
Answer
Laughing/smiling	71	53	34	12.24	.00**
Mouth closure	20	30	6	8.23	.02*
Looking happy	10	20	8	–a	.33
Imitation
Eye contact/gaze	24	23	20	0.27	.87
Words/speech	12	10	8	–a	.93

^aAs a result of low cell frequencies no chi-square value can be calculated. Fisher’s exact test p-value is given

*p < .05; **p < .01