Rifat Atun conceived the review with Josip Car, and will advise all stages of the study, providing clinical and policy perspectives. He will oversee the search and selection process, including the construction and implementation of search and quality appraisal strategies. He will contact authors of papers for additional information, and analyse data from the selected papers.

Josip Car is the contact author for the reviews and will coordinate all stages of the study, providing clinical and consumer perspectives. He conceived and designed the review with Rifat Atun , and oversaw the protocol stage. He will advise on designing the search strategy, screening search results against inclusion criteria, and appraising quality of the papers. He will interpret the data and contribute to writing the review.

Ipek Gurol‐Urganci developed the protocols. She will lead the search process and assist in screening the papers. She will collect data for the review, analyse and interpret the data and contribute to writing the review, providing methodological and policy perspectives.

Vlasta Vodopivec Jamšek developed the protocols. She will lead the screening and quality appraisal process and assist in undertaking searches. She will collect data for the review, analyse and interpret the data and contribute to writing the review, providing clinical and consumer perspectives.

Thyra de Jongh will coordinate data extraction and management and assist in screening and appraising papers. She will collect data for the review and enter data into RevMan. She will analyse and interpret the data and contribute to writing the review, providing a methodological perspective.