Data and fits are obtained as for , but using the myelinated counts. Two regular difference fit curves are shown:

and

, with

in both cases. Systematic deviations from data around

are obvious, but fit quality remains tolerable with a confidence level of 53.45% for

. Even larger

can increase the confidence level to about 70%. For comparison, dispersive fits with orders

and

are also shown. Their

is almost a factor two larger, rendering their confidence level negligible. Fits with the long-wavelength propagator are not show, but fail drastically, cf. . The curves marked with a

show additional fits for diameters

only, i.e., without the first four data bins. Then one can find optimal fit orders for both propagators. These fits are of comparable, excellent quality compared to the reduced data set. But both predict too many small diameter fibres, and hence have negligible confidence levels compared to the full data set, with the dispersive

again being about two times larger.

## PubMed Commons