Table 1. Data of each case.

Case No. (gender)	Age at crawling (days)	Duration of crawling (days)	Age at independent walking (days)	Number of videos taken	Cumulative number of crawling variations
Case A (m)	251	174	425	11	45
Case B (m)	245	141	386	13	49
Case C (m)	363	127	490	9	31
Case D (m)	266	156	422	15	59
Case E (f)	267	154	421	10	38
Case F (f)	286	106	392	8	26
Case G (f)	284	166	450	11	46
Case H (f)	250	166	416	12	48
Case I (f)	228	175	403	15	49
Case J (m)	219	144	363	13	54
Case K (m)	197	128	325	15	42
Case L (m)	226	161	387	16	63
Case M (m)	267	98	365	11	39
Case N (m)	263	217	480	21	38
Case O (f)	361	66	427	10	32
Case P (m)	285	147	432	13	65
Case Q (m)	318	91	409	9	38
Case R (m)	253	212	465	19	30
Case S (m)	341	119	460	13	23
Mean	272.1	144.6	416.7	12.8	42.9
SD	46.1	38.7	42.0	3.4	12.0

SD: standard deviation.