Statistical analysis of structural parameters of crystals with colquiriite structure - LiMM'F-6- retrieved from the inorganic crystal structure database, and from literature, has revealed strong correlations between some of them. The type and degree of correlation is site- and constitution-dependent. Therefore, except the total sample, some selected subsets of data are analysed with only one variable ion occupying the given site. Structural parameters are not equally sensitive to changes imposed by the change of the crystal constitution. The pairs of subsets with the general formulae LiSrM'F-6 and LiCaM'F-6, as well as LiMAlF6 and LiMGaF6, exhibit similar dependencies between structural parameters. The results, presented, can be used to predict the changes of the structure while growing new crystals with colquiriite structure. The results of principal component analysis clearly show that the first factor explains most of the variation of structural data. It has a geometric nature and correlates with the effective radii of the doping ions.