Josip Car conceived the review together with Rifat Atun. He is the contact author for the reviews and coordinated all stages of the study, including the protocol stage. He advised on designing the search strategy, screening search results against inclusion criteria, and appraising quality of the papers. He assisted in interpreting the data and contributed to writing the review, providing clinical and consumer perspectives and will be responsible for leading the update of this review.

Ipek Gurol‐Urganci developed the protocols. She has lead the search process and assisted in screening the papers. She collected, analysed and interpreted data and contributed to writing the review, providing methodological and policy perspectives. 

Vlasta Vodopivec Jamek developed the protocols. She has been involved in the screening and quality appraisal process and assisted in undertaking searches. She has collected, analysed and interpreted data and contributed to writing the review, providing clinical and consumer perspectives.

Thyra de Jongh coordinated data extraction and management and was involved in the screening and quality appraisal process. She has collected, analysed and interpreted data and contributed to writing the review, providing a methodological perspective.

Rifat Atun provided general direction for the studies and assisted in writing and revising the review.