We consider Adler D-function for the vector and scalar correlators with recent QCD analysis at N⁴LO approximation. The portion of perturbative coefficients of these observable containing the leading power of b, the first beta-function coefficient, is resummed to all-orders. The factorial behavior of coefficients allows us to use the Borel transformation to reveal the existent singularities as renormalons. CORGI approach is employed to avoid the renormalization dependence of the observable. In addition to the CORGI approach, the calculations of the standard perturbative QCD approach which uses the [Formula: see text] scheme with a physical choice of renormalization scale, are also presented. A comparison between the results of the standard and CORGI approaches for R_τand Higgs decay width is done. The comparison anticipates a better result for the CORGI approach. As an adjunct to these studies, the difference between the all order and fixed order result at N⁴LO approximation is used to estimate the uncertainty in [Formula: see text] extracted from R_τmeasurements. We find at N⁴LO approximation a smaller uncertainty with respect to the previous result which has been done at N⁴LO approximation.