A preliminary sustainability assessment framework for traditional medicinal knowledge built from an existing ethnographic record: the Gayo ethnomedicine system, Lut Tawar, Central Aceh, Indonesia

Traditional medicinal knowledge (TMK) links human health, biodiversity and cultural continuity, yet sustainability-indicator frameworks rarely assess it directly. Our contribution is methodological: we show how an existing ethnographic record can be turned into a transparent, traceable sustainability assessment framework. We worked only from a 2024 ethnographic technical report on the Gayo community of Lut Tawar, Central Aceh, Indonesia, with no new fieldwork and no informant-level data. Its 51-species inventory (158 use reports across 67 ailment labels) and 65-entry remedy inventory were restructured into a dataset, from which we computed reported-use breadth (RUB), documented corpus consensus (DCC, calculated with the Informant Consensus Factor formula) and formulation richness (FR). We coded the report's account of knowledge erosion into 16 explicitly stated mechanisms (structural 6, cultural 5, ecological 5) and organised both profiles in a Pressure–State–Response structure, the Traditional Medicinal Knowledge Sustainability Profile (TMK-SP), without collapsing them into one score. RUB was right-skewed (median 2; ten species held 73 of 158 use reports). DCC was low (pooled 0.15; at most 0.27 in categories with eight or more use reports) and rose with category size. Sixteen of 65 ailments (24.6%; bootstrap 95% CI 13.8–35.4%) had a single recorded remedy. The composite pressure score (0.89; 0.84–0.96 under random weights) shows that erosion is documented in all three dimensions, not how severe it is. TMK-SP is a preliminary diagnostic profile, not a validated measure of sustainability; informant-level surveys, voucher specimens, expert validation and repeat surveys are needed before it can support comparison across sites.