Dropout Rate in Digital Health Interventions for the Prevention of Skin Cancer: Systematic Review, Meta-analysis, and Metaregression - Juan-Carlos Hernández-Rodríguez; Cristina García-Muñoz; Juan Ortiz-Álvarez; Francesc Saigí-Rubió; Julián Conejo-Mir; Jose-Juan Pereyra-Rodriguez (Journal of Medical Internet Research, 2022)