The SPA surveys and DHS surveys conducted under the DHS Program are not like surveys. These are independent surveys. So they are not conducted in the same clusters. The only way to link the data is through geographical information, GIS information is collected in both surveys. But DHS does not provide a standard method for the link, it is upon to the data users who decide how to link based on their research aims. The survey design information is usually given in chapter 1 of the final report for both surveys. For DHS surveys, the detailed survey design and methodology is given in Appendix A of the final survey report.