Objectives: We conducted a comparative review of clinical practice guideline development handbooks. We aimed to identify the main guideline development tasks, assign weights to the importance of each task using expert opinions and identify the handbooks that provided a comprehensive coverage of the tasks. Methods: We systematically searched and included handbooks published (in English language) by national, international or professional bodies responsible for evidenced-based guideline development. We reviewed the handbooks to identify the main guideline development tasks and scored each handbook for each task from 0 (the handbook did not mention the task) to 2 (the task suitably addressed and explained), and calculated a weighted score for each handbook. The tasks included in over 75% of the handbooks were considered as 'necessary' tasks. Result: Nineteen guideline development handbooks and twenty seven main tasks were identified. The guideline handbooks' weighted scores ranged from 100 to 220. Four handbooks scored over 80% of the maximum possible score, developed by the National Institute for Health and Clinical Excellence, Swiss Centre for International Health, Scottish Intercollegiate Guidelines Network and World Health Organization. Necessary tasks were: selecting the guideline topic, determining the guideline scope, identifying relevant existing guidelines, involving the consumers, forming guideline development group,, developing clinical questions, systematic search for evidence, selecting relevant evidence, appraising identifies research evidence, making group decision, grading available evidence, creating recommendations, final stakeholder consultation, guideline implementation strategies, updating recommendations and correcting potential errors. Discussion: Adequate details for evidence based development of guidelines were still lacking from many handbooks. The tasks relevant to ethical issues and piloting were missing in most handbooks. The findings help decision makers in identifying the necessary tasks for guideline development, provide an updated comparative list of guideline development handbooks, and provide a checklist to assess the comprehensiveness of guideline development processes.
