Effects of occupational health promotion interventions on health-related outcomes among employees of small businesses and self-employed individuals: A systematic review. - Willeke, Kristina; Janson, Patrick; Kirchner, Anna; Tischer, Christina; D'Souza, Arun; Heuschmann, Peter U.; Zapf, Andreas; Wildner, Manfred; Stupp, Carolin; Keil, Thomas (Work, 2024)