Filament width (FWHM) as a function of central column density (N_H2) for all models analysed. Colours depict the particular model as indicated by the legend. Filled symbols depict SL models while shaded symbols depict CR-only models. Circles indicate models with an initially transcritical mass-to-flux ratio (μ₀ = 1.1) while squares indicate models with an initially super-critical mass-to-flux ratio (μ₀ = 2.0). Also included are filament widths based on observations of IC5146 (Arzoumanian et al. 2011, diamonds), the Galactic cold core survey (Juvela et al. 2012, pluses) and the DR21 filament within the Cygnus X region (Hennemann et al. 2012, X’s).The solid black line depicts the computed Jeans length as a function of column density [] for a gas temperature of 10 K. The shaded area within the dashed lines indicates the region occupied by the filaments analysed in Arzoumanian et al. (2011). The errors in our FWHM values are too small to be seen on the plot.