Sampling issues in quantitative analysis of dendritic spines morphology

BMC Bioinformatics

Table 1 Minimal spine population (number of cells per group) which guarantees false negative rate below 5%

Modeled change	t-test p-value	Parameter studied	Required number of cells per group
in spines variable			(with 15, 30, 60 spines/cell)
10%	0.001	area	166	84	43
		length	137	70	35
		head-width	66	35	19
20%	0.001	area	47	24	14
		length	39	21	13
		head-width	21	12	8
50%	0.001	area	13	8	6
		length	11	7	5
		head-width	7	5	4
10%	0.01	area	119	62	31
		length	101	51	27
		head-width	49	26	14
20%	0.01	area	33	19	10
		length	29	15	8
		head-width	15	9	6
50%	0.01	area	9	6	4
		length	8	5	4
		head-width	5	4	3

Simulation results with various numbers of cells, spines per cell, p-values of the test, strength of systematic change and parameters studied were used to set the limits on number of analyzed cells per group in order to guarantee that the false negative rate falls below 5%. The systematic changes were modeled by the linear growth. The test groups were compared by Student’s two-tailed t-test.

ISSN: 1471-2105