Supplier certification, selection effects and environmental strategy in palm oil supply chains systematic review materials (RSPO and ISPO, Indonesian smallholders)

Materials for a systematic review, following PRISMA 2020, of evidence on Roundtable on Sustainable Palm Oil (RSPO) and Indonesian Sustainable Palm Oil (ISPO) certification among Indonesian oil palm smallholders. The review asks what conditions readiness and participation, how constraints differ between a voluntary and a mandatory scheme, and what reported outcomes can and cannot attribute to certification. The project holds the retrospectively archived protocol, the search code and per-query retrieval counts (OpenAlex complete retrieval, a Crossref supplement and Scopus exports), the deduplication and pre-screen logs, the title-and-abstract screening ledger for 807 records (138 included, 47 referred to full text), the agreement between manual and automated screening, a lenient-criteria sensitivity screen, and the figures. Full-text and appraisal records are added once that stage is complete.