Semnan University International Journal of Nonlinear Analysis and Applications 2008-6822 14 1 2023 01 01 A difference scheme using a parametric spline for differential difference equation with twin layers 2469 2479 7276 10.22075/ijnaa.2022.28237.3841 EN B.S.L. Soujanya G Department of Mathematics, University College for Women, Kakatiya University, Warangal, India Kumar Ragula Department of Mathematics, Rajiv Gandhi University of Knowledge and Technologies, Basar, India Phaneendra K Department of Mathematics, University College of Science, Osmania University, Hyderabad, India Journal Article 2022 08 29 In this study, a parametric spline approach is used to evaluate the solution of differential-difference equations with delay and advanced parameters having twin layers. Using the continuity condition of the first-order derivative of the spline at the interior node, the difference scheme is derived. Thenon-standard finite differences for the first derivatives are employed in the scheme to increase the precision of the solution. According to an analysis of the suggested approach, its fourth-order convergence is established.  Maximum absolute errors for the examples chosen from the literature are tabulated. To demonstrate the effectiveness of the method, numerical results are shown along with comparisons to other methods. https://ijnaa.semnan.ac.ir/article_7276_7f91c1380e5124a0daca402cfb7873a7.pdf