Organizational diagnosis plays a fundamental role in the success of organizational change initiatives, because on the one hand it is the basis for selecting appropriate management interventions and on the other hand it determines the level of readiness of the organization to accept and implement change. Despite the extensive emphasis in the management and behavioral sciences literature on the importance of organizational diagnosis, little attention has been paid to the diagnosis process itself and especially the role of cognitive biases in weakening the quality of organizational diagnosis and decision-making. Cognitive biases, as systematic patterns of error in perception, judgment, and interpretation of information, can cause the diagnosis process to deviate from objective evidence and lead to incorrect decisions and the failure of change programs. Accordingly, the aim of the present article is to present an integrated, systematic, and evidence-based framework for reducing cognitive biases and improving diagnostic decisions in organizations, which can be used in various industries and fields, especially in the electricity industry. This article is of a developmental-applied type and was conducted with a mixed approach. In the qualitative part, through a systematic and integrated review of scientific literature published between 2010 and 2025, theoretical foundations related to cognitive biases, organizational recognition process, and bias reduction strategies have been extracted and analyzed. In the quantitative part, the proposed framework was validated with the opinions of 15 experts with simultaneous academic and managerial experience. Data analysis was performed using content analysis and theme analysis. The findings led to the identification of three main themes including "knowledge", "diagnosis process" and "cognitive bias reduction", which were organized in a three-layer and hierarchical framework. The knowledge layer includes knowledge of signs, systems, standards and solutions; the diagnosis process layer includes the stages of information collection, criterion-setting, evaluation and validation along with feedback and iteration mechanisms; and the cognitive bias reduction layer plays the role of controlling the cognitive quality of the entire diagnosis process by focusing on individual cognitive considerations and designing the decision-making environment. In addition to its theoretical value, the proposed framework provides practical tools for managers and creates a suitable platform for the development of evidence-based decision-making in organizations.