Integrating qualitative and quantitative ethnomedicinal knowledge: A comprehensive assessment of traditional medicine in West Hararghe Zone, Oromia, Ethiopia

Traditional medicine remains the primary healthcare system for 80–90% of the Ethiopian population, particularly in rural areas, yet comprehensive ethnobotanical studies integrating quantitative indices with qualitative healers’ perspectives remain limited in the West Hararghe Zone. This mixed-methods study documented medicinal plants used for human and veterinary healthcare across eight woredas and explored traditional diagnostic practices, disease aetiologies, and knowledge transmission. Data were collected from 120 informants through semi-structured interviews, focus group discussions, participant observation, guided field walks, and case narratives. Ethnobotanical indices, including Use Value (UV), Relative Frequency of Citation (RFC), Informant Consensus Factor (ICF), Fidelity Level (FL), and a 40-point Drug Lead Priority matrix, were combined with thematic analysis. A total of 157 medicinal plant species representing 64 families and 123 genera were recorded, with Fabaceae being the dominant family (9.6%). Herbs (41.2%) collected mainly from wild habitats (68.4%) predominated, while leaves (38.5%) were the most frequently used plant part. Decoction (44.9%) and oral administration (61.2%) were the principal preparation and application methods. Gastrointestinal disorders showed the highest informant consensus (ICF = 0.92), whereas Croton macrostachyus exhibited the highest fidelity level for wound treatment (FL = 96.7%). Eleven species achieved high drug-lead priority scores (≥ 28/40), including three promising candidates (Maerua angolensis, Laggera crispata, and Cadaba farinosa). Traditional healers recognized three major disease aetiologies and employed five complementary diagnostic approaches, with 82% integrating traditional and biomedical healthcare. Notably, 28% of the documented medicinal plants were classified as endangered. These findings highlight the rich ethnomedicinal knowledge of West Hararghe, identify promising species for future pharmacological investigation, and emphasize the urgent need for conservation and preservation of traditional knowledge.